efl/doc/ecore_examples.dox

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/**
* @page ecore_examples Ecore Examples
*
* Here is a page with some Ecore examples explained:
*
* @li @ref ecore_time_functions_example_c
* @li @ref ecore_timer_example_c
* @li @ref ecore_idler_example_c
* @li @ref ecore_job_example_c
* @li @ref ecore_event_example_01_c
* @li @ref ecore_event_example_02_c
* @li @ref ecore_fd_handler_example_c
* @li @ref ecore_poller_example_c
* @li @ref ecore_con_lookup_example_c
* @li @ref ecore_con_url_download_example_c
* @li @ref ecore_con_server_simple_example_c
* @li @ref ecore_con_client_simple_example_c
* @li @ref ecore_evas_callbacks_example_c
* @li @ref ecore_evas_object_example_c
* @li @ref ecore_evas_basics_example_c
* @li @ref Ecore_Evas_Window_Sizes_Example_c
* @li @ref Ecore_Evas_Buffer_Example_01_c
* @li @ref Ecore_Evas_Buffer_Example_02_c
* @li @ref Ecore_exe_simple_example_c
* @li @ref ecore_imf_example_c
*/
/**
* @page ecore_time_functions_example_c ecore_time - Differences between time functions
*
* This example shows the difference between calling ecore_time_get(),
* ecore_loop_time_get() and ecore_time_unix_get().
*
* It initializes ecore, then sets a timer with a callback that, when called,
* will retrieve the system time using these 3 different functions. After
* displaying the time, it sleeps for 1 second, then call display the time
* again using the 3 functions.
*
* Since everything occurs inside the same main loop iteration, the internal
* ecore time variable will not be updated, and calling ecore_loop_time_get()
* before and after the sleep() call will return the same result.
*
* The two other functions will return a difference of 1 second, as expected.
* But ecore_time_unix_get() returns the number of seconds since 00:00:00 1st
* January 1970, while ecore_time_get() will return the time since a
* unspecified point, but that never goes back in time, even when the timezone
* of the machine changes.
*
* @note The usage of ecore_loop_time_get() should be preferred against the
* two other functions, for most time calculations, since it won't produce a
* system call to get the current time. Use ecore_time_unix_get() when you need
* to know the current time and date, and ecore_time_get() when you need a
* monotonic and more precise time than ecore_loop_time_get().
*
* @include ecore_time_functions_example.c
*/
/**
* @page ecore_timer_example_c ecore timers - Scheduled events
* @dontinclude ecore_timer_example.c
*
* This example shows how to setup timer callbacks. It starts a timer that will
* tick (expire) every 1 second, and then setup other timers that will expire
* only once, but each of them will affect the first timer still executing with
* a different API, to demonstrate its usage. To see the full code for this
* example, click @ref ecore_timer_example.c "here".
*
* To demonstrate this, let's define some constants that will determine at which
* time each timer will expire:
*
* @until INTERVAL1
*
* These constants should tell by themselves what will be the behavior of the
* program, but I'll explain it anyway. The first timer is set to tick every 1
* second, but all the other timers until the 6th one will be started
* concurrently at the beginning of the program. Each of them will expire at the
* specified time in these constants:
*
* @li The timer2, after 3 seconds of the program being executed, will add a delay
* of 3 seconds to timer1;
* @li The timer3 will pause timer1 at 8.2 seconds;
* @li timer4 will resume timer1 at 11.0 seconds;
* @li timer5 will will change the interval of timer1 to 2 seconds;
* @li timer6 will stop timer1 and start timer7 and timer8, with 1.1 and 1.2
* seconds of interval, respectively; it also sets the precision to 0.2 seconds;
* @li timer7 and timer8 will just print their expiration time.
*
* @until ecore_time_get
* @until }
*
* As almost all the other examples, we create a context structure to pass to
* our callbacks, so they can have access to the other timers. We also store the
* time of the program start in @c _initial_time, and use the function
* @c _get_current_time to retrieve the current time relative to that time. This
* will help demonstrate what is going on.
*
* Now, the behavior and relationship between the timers that was described
* above is dictated by the following timer callbacks:
*
* @until _timer6_cb
* @until }
*
* It's possible to see the same behavior as other Ecore callbacks here,
* returning @ref ECORE_CALLBACK_RENEW when the timer needs to continue ticking,
* and @ref ECORE_CALLBACK_CANCEL when it needs to stop its execution. Also
* notice that later on our program we are checking for the timers pointers in
* the context to see if they are still executing before deleting them, so we
* need to set these timer pointers to @c NULL when we are returning @ref
* ECORE_CALLBACK_CANCEL. Otherwise the pointer would still be not @c NULL, but
* pointing to something that is invalid, since the timer would have already
* expired without renewing.
*
* Now the main code, which will start the timers:
*
* @until ecore_shutdown
* @until }
*
* This code is very simple. Just after starting the library, it will save the
* current time to @c _initial_time, start all timers from 1 to 6, and begin the
* main loop. Everything should be running right now, displaying the time which
* each timer is expiring, and what it is doing to affect the other timers.
*
* After returning from the main loop, every timer is checked to see if it's
* still alive and, in that case, deleted, before finalizing the library. This
* is not really necessary, since ecore_shutdown() will already delete them for
* you, but it's good practice if you have other things going on after this
* point that could restart the main loop.
*
*/
/**
* @page ecore_idler_example_c ecore idle state - Idlers, enterers and exiters
*
* This example demonstrates how to manage the idle state of the main loop. Once
* a program knows that the main loop is going to enter in idle state, it could
* start doing some processing until getting out of this state.
*
* To exemplify this, we also add events and a timer to this program, so we can
* see the idle exiter callback being called before processing the event and/or
* timer, the event/timer callback being called (processed), then the idle
* enterer being called before entering in idle state again. Once in idle, the
* main loop keeps calling the idler callback continuously until a new event or
* timer is received.
*
* First, we declare a struct that will be used as context to be passed to
* every callback. It's not useful everywhere, since this example is very
* simple and doesn't do anything other than printing messages, but using this
* context will make it a little bit more real. Our context will be used to
* delete the timer, idler, idle enterer and exiter, and the event handler, and
* also to count how many times the idler was called.
*
* Then we start declaring callbacks for the idle enterer, idle exiter and the
* idler itself. Idle enterer and exiter callbacks just print a message saying
* that they were called, while the idler, in addition to printing a message
* too, also sends an event every 10 times that it is called, incrementing the
* context count variable. This event will be used to make the main loop exit
* the idle state and call the event callback.
*
* These callbacks return @ref ECORE_CALLBACK_RENEW, since we want them to keep
* being called every time the main loop changes to/from idle state. Otherwise,
* if we didn't want them to be called again, they should return @ref
* ECORE_CALLBACK_CANCEL.
*
* The next function declared is the event callback @c _event_handler_cb. It
* will check if the idler was called more than 100 times already @c
* (ctxt->count > 100), and will delete the idler, idle enterer and exiter, the
* timer (if it still exists), and request that the main loop stop running. Then
* it returns @ref ECORE_CALLBACK_DONE to indicate that the event shouldn't be
* handled by any other callback.
*
* Finally, we add a callback to the timer, that will just print a message when
* it is called, and this will happen only once (@ref ECORE_CALLBACK_CANCEL is
* being returned). This timer callback is just here to show that the main loop
* gets out of idle state when processing timers too.
*
* The @b main function is simple, just creates a new type of event that we will
* use to demonstrate the event handling together with the idle state, adds the
* callbacks that we declared so far, fill the context struct, and starts
* running the main loop.
*
* @note We use timer and event callbacks to demonstrate the idle state
* changing, but it also happens for file descriptor handlers, pipe handlers,
* etc.
*
* @include ecore_idler_example.c
*/
/**
* @page ecore_job_example_c ecore_job - Queuing tasks
*
* This example shows how an @ref Ecore_Job can be added, how it can be
* deleted, and that they always execute in the added order.
*
* First, 2 callback functions are declared, one that prints strings passed to
* it in the @c data pointer, and another one that quits the main loop. In the
* @c main function, 3 jobs are added using the first callback, and another one
* is added using the second one.
*
* Then the second added job is deleted just to demonstrate the usage of
* ecore_job_del(), and the main loop is finally started. Run this example to
* see that @c job1, @c job3 and @c job_quit are ran, in this order.
*
* @include ecore_job_example.c
*/
/**
* @page ecore_event_example_01_c Handling events example
* This example shows the simplest possible way to register a handler for an
* ecore event, this way we can focus on the important aspects. The example will
* start the main loop and quit it when it receives the ECORE_EVENT_SIGNAL_EXIT
* event. This event is triggered by a SIGTERM(pressing ctrl+c).
*
* So let's start with the function we want called when we receive the event,
* instead of just stopping the main loop we'll also print a message, that's
* just so it's clear that it got called:
* @dontinclude ecore_event_example_01.c
* @skip static
* @until }
* @note We return ECORE_CALLBACK_DONE because we don't want any other handlers
* for this event to be called, the program is quitting after all.
*
* We then have our main function and the obligatory initialization of ecore:
* @until ecore_init
*
* We then get to the one line of our example that makes everything work, the
* registering of the callback:
* @until handler_add
* @note The @c NULL there is because there is no need to pass data to the
* callback.
*
* And the all that is left to do is start the main loop:
* @until }
*
* Full source code for this example: @ref ecore_event_example_01.c.
*/
/**
* @page ecore_event_example_02_c ecore events and handlers - Setup and use
* This example shows how to create a new type of event, setup some event
* handlers to it, fire the event and have the callbacks called. After
* finishing, we delete the event handlers so no memory will leak.
*
* See the full source code for this example @ref ecore_event_example_02.c
* "here".
*
* Let's start the example from the beginning:
*
* @dontinclude ecore_event_example_02.c
* @until _event_type
*
* First thing is to declare a struct that will be passed as context to the
* event handlers. In this structure we will store the event handler pointers,
* and two strings that will be used by the first event handler. We also will
* use a global integer to store the event type used for our event. It is
* initialized with 0 in the beginning because the event wasn't created yet.
* Later, in the main function we will use ecore_event_type_new() to associate
* another value to it. Now the event handler callbacks:
*
* @until }
*
* This is the first event handler callback. It prints the event data received
* by the event, and the data passed to this handler when it was added. Notice
* that this callback already knows that the event data is an integer pointer,
* and that the handler data is a string. It knows about the first one because
* this is based on the type of event that is going to be handled, and the
* second because it was passed to the ecore_event_handler_add() function when
* registering the event handler.
*
* Another interesting point about this callback is that it returns @ref
* ECORE_CALLBACK_DONE (0) if the event data is even, swallowing the event and
* don't allowing any other callback to be called after this one for this event.
* Otherwise it returns @ref ECORE_CALLBACK_PASS_ON, allowing the event to be
* handled by other event handlers registered for this event. This makes the
* second event handler be called just for "odd" events.
*
* @until ECORE_CALLBACK_DONE
* @until }
*
* The second event handler will check if the event data is equal to 5, and if
* that's the case, it will change the event handler data of the first event
* handler to another string. Then it checks if the event data is higher than
* 10, and if so, it will request the main loop to quit.
*
* An interesting point of this example is that although the second event
* handler requests the main loop to finish after the 11th event being received,
* it will process all the events that were already fired, and call their
* respective event handlers, before the main loop stops. If we didn't want
* these event handlers to be called after the 11th event, we would need to
* unregister them with ecore_event_handler_del() at this point.
*
* Now some basic initialization of the context, and the Ecore library itself:
*
* @until type_new
*
* This last line is interesting. It creates a new type of event and returns a
* unique ID for this event inside Ecore. This ID can be used anywhere else in
* your program to reference this specific type of event, and to add callbacks
* to it.
*
* It's common if you are implementing a library that declares new types of
* events to export their respective types as extern in the header files. This
* way, when the library is initialized and the new type is created, it will be
* available through the header file to an application using it add some
* callbacks to it. Since our example is self-contained, we are just putting it
* as a global variable.
*
* Now we add some callbacks:
*
* @until ctxt);
*
* This is very simple. Just need to call ecore_event_handler_add() with the
* respective event type, the callback function to be called, and a data pointer
* that will be passed to the callback when it is called by the event.
*
* Then we start firing events:
*
* @until }
*
* This @c for will fire 16 events of this type. Notice that the events will be
* fired consecutively, but any callback will be called yet. They are just
* called by the main loop, and since it wasn't even started, nothing happens
* yet. For each event fired, we allocate an integer that will hold the number
* of the event (we are arbitrarily creating these numbers just for
* demonstration purposes). It's up to the event creator to decide which type of
* information it wants to give to the event handler, and the event handler must
* know what is the event info structure for that type of event.
*
* Since we are not allocating any complex structure, just a simple integer, we
* don't need to pass any special free function to ecore_event_add(), and it
* will use a simple @c free on our data. That's the default behavior.
*
* Now finishing our example:
*
* @until }
*
* We just start the main loop and watch things happen, waiting to shutdown
* Ecore when the main loop exits and return.
*/
/**
* @page ecore_fd_handler_example_c ecore fd handlers - Monitoring file descriptors
* @dontinclude ecore_fd_handler_example.c
*
* This is a very simple example where we will start monitoring the stdin of the
* program and, whenever there's something to be read, we call our callback that
* will read it.
*
* Check the full code for this example @ref ecore_fd_handler_example.c "here".
*
* This seems to be stupid, since a similar result could be achieved by the
* following code:
*
* @code
* while (nbytes = read(STDIN_FILENO, buf, sizeof(buf)))
* {
* buf[nbytes - 1] = '\0';
* printf("Read %zd bytes from input: \"%s\"\n", nbytes - 1, buf);
* }
* @endcode
*
* However, the above code is blocking, and won't allow you to do anything else
* other than reading the input. Of course there are other methods to do a
* non-blocking reading, like setting the file descriptor to non-blocking and
* keep looping always checking if there's something to be read, and do other
* things otherwise. Or use a @c select call to watch for more than one file
* descriptor at the same time.
*
* The advantage of using an @ref Ecore_Fd_Handler is that you can monitor a
* file descriptor, while still iterating on the Ecore main loop. It will allow
* you to have timers working and expiring, events still being processed when
* received, idlers doing its work when there's nothing happening, and whenever
* there's something to be read from the file descriptor, your callback will be
* called. And it's everything monitored in the same main loop, no threads are
* needed, thus reducing the complexity of the program and any overhead caused
* by the use of threads.
*
* Now let's start our program. First we just declare a context structure that
* will be passed to our callback, with pointers to our handler and to a timer
* that will be used later:
*
* @until };
*
* Then we will declare a prepare_callback that is called before any fd_handler
* set in the program, and before the main loop select function is called. Just
* use one if you really know that you need it. We are just putting it here to
* exemplify its usage:
*
* @until }
*
* Now, our fd handler. In its arguments, the @c data pointer will have any data
* passed to it when it was registered, and the @c handler pointer will contain
* the fd handler returned by the ecore_main_fd_handler_add() call. It can be
* used, for example, to retrieve which file descriptor triggered this callback,
* since it could be added to more than one file descriptor, or to check what
* type of activity there's in the file descriptor.
*
* The code is very simple: we first check if the type of activity was an error.
* It probably won't happen with the default input, but could be the case of a
* network socket detecting a disconnection. Next, we get the file descriptor
* from this handler (as said before, the callback could be added to more than
* one file descriptor), and read it since we know that it shouldn't block,
* because our fd handler told us that there's some activity on it. If the
* result of the read was 0 bytes, we know that it's an end of file (EOF), so we
* can finish reading the input. Otherwise we just print the content read from
* it:
*
* @until }
*
* Also notice that this callback returns @ref ECORE_CALLBACK_RENEW to keep
* being called, as almost all other Ecore callbacks, otherwise if it returns
* @ref ECORE_CALLBACK_CANCEL then the file handler would be deleted.
*
* Just to demonstrate that our program isn't blocking in the input read but
* still can process other Ecore events, we are going to setup an @ref
* Ecore_Timer. This is its callback:
*
* @until }
*
* Now in the main code we are going to initialize the library, and setup
* callbacks for the file descriptor, the prepare callback, and the timer:
*
* @until timer_add
*
* Notice that the use of ecore_main_fd_handler_add() specifies what kind of
* activity we are monitoring. In this case, we want to monitor for read (since
* it's the standard input) and for errors. This is done by the flags @ref
* ECORE_FD_READ and @ref ECORE_FD_ERROR. For the three callbacks we are also
* giving a pointer to our context structure, which has pointers to the handlers
* added.
*
* Then we can start the main loop and see everything happening:
*
* @until }
*
* In the end we are just deleting the fd handler and the timer to demonstrate
* the API usage, since Ecore would already do it for us on its shutdown.
*/
/**
* @page ecore_poller_example_c ecore poller - Repetitive polling tasks
* @dontinclude ecore_poller_example.c
*
* This example shows how to setup, and explains how an @ref Ecore_Poller is
* called. You can @ref ecore_poller_example.c "see the full source code here".
*
* In this example we store the initial time of the program just to use as
* comparison to the time when the poller callbacks are called. It will be
* stored in @c _initial_time :
*
* @until initial_time
*
* Then next step is to define the poller callback. This callback assumes that a
* @c data pointer is passed to it on creation, and is a string just used to
* identify the poller. The callback prints this string and the time since the
* program started, and returns @ref ECORE_CALLBACK_RENEW to keep being called.
*
* @until }
*
* Now in the main function we initialize Ecore, and save the initial time of
* the program, so we can compare it later with the time that the pollers are
* being called:
*
* @until initial_time
*
* Then we change the poll interval to 0.3 seconds (the default is 0.125
* seconds) just to show the API usage.
*
* Finally, we create two pollers, one that will be called every 4 ticks, and
* another one that will be called every 8 ticks. This means the the first
* poller interval will be around 1.2 seconds, and the second one will be
* around 2.4 seconds. But the most important point is: since the second poller
* interval is a multiple of the first one, they will be always synchronized.
* Ecore calls pollers that are in the "same tick" together. It doesn't go back
* to the main loop and check if there's another poller to execute at this
* time, but instead it calls all the pollers registered to this "tick" at the
* same time. See the description of ecore_poller_add() for more details. This
* is easy to see in the time printed by both of them.
*
* If instead of two synchronized pollers, we were using two different timers,
* one with interval of 1.2 seconds and another one with an interval of 2.4
* seconds, there would be no guarantee that they would be totally in sync. Some
* delay in the execution of another task, or even in the task called in the
* callback, could make them get out of sync, forcing Ecore's main loop to wake
* up more than necessary.
*
* Well, this is the code that create these two pollers and set the poll
* interval, then starts the main loop:
*
* @until ecore_main_loop_begin
*
* If you hit CTRL-C during the execution of the program, the main loop will
* quit, since there are some signal handlers already set by default to do this.
* So after the main loop begin call, we change the second poller's interval to
* 16 ticks, so it will happen each 4.8 seconds (or each 4 times that the first
* poller is called).
*
* This means: the program is started, the first poller is called each 4 ticks
* and the second is called each 8 ticks. After CTRL-C is used, the second
* poller will be called each 16 ticks.
*
* @until }
*
* The rest of the program is just deleting the pollers and shutting down the
* library.
*/
/**
* @page ecore_con_lookup_example_c Ecore_Con - DNS lookup
*
* This is a very simple example that shows how to make a simple DNS lookup
* using ecore_con_lookup().
*
* It's possible to see in the beginning of the main function that we are using
* the arguments passed via command line. This is the address that we are going
* to make the DNS lookup on.
*
* The next step is to initialize the libraries, and just call
* ecore_con_lookup(). This function will get the string that contains the
* address to be resolved as first parameter, then a callback that will be
* called when the resolve stage is done, and finally a data pointer that will
* be passed to the callback.
*
* This function is asynchronous, and the callback will be called only on
* success. If there was an error during the resolve stage, there's no way to
* know about that. It's only possible to know about errors when setting up the
* lookup, by looking at the return code of the ecore_con_lookup() function.
*
* The callback @c _lookup_done_cb passed as argument to ecore_con_lookup() just
* prints the resolved canonical name, IP, address of the sockaddr structure,
* and the length of the socket address (in bytes).
*
* Finally, we start the main loop, and after that we finalize the libraries and
* exit.
*
* This is the code for this simple example:
*
* @include ecore_con_lookup_example.c
*/
/**
* @page ecore_con_url_download_example_c Ecore_Con_Url - downloading a file
*
* This is a simple example that shows how to download a file using @ref
* Ecore_Con_Url. The full source code for this example can be found at @ref
* ecore_con_url_download_example.c.
*
* First we are setting some callbacks for events that will be sent when data
* arrives in our connection (the data is the content of the file being
* downloaded), and when the download is completed. The @c _url_progress_cb and
* @c _url_complete_cb are these callbacks:
*
* @dontinclude ecore_con_url_download_example.c
* @skip struct
* @until main_loop_quit
* @until }
*
* Notice that we also declared a struct that will hold how many bytes were
* downloaded through this object. It will be set in the @c main function using
* ecore_con_url_data_set().
*
* In the next step, on the @c main function, we open a file where we are going
* to save the content being downloaded:
*
* @until open(
* @until }
*
* With the file successfully open, let's create our @ref Ecore_Con_Url object.
* For this, we initialize the libraries and create the object:
*
* @until }
*
* Then we allocate and set the data struct to the connection object, and set a
* file descriptor from our previously open file to it. We also add the event
* handlers (callbacks) to the events that will be emitted on data being
* received and download complete:
*
* @until complete_cb
*
* Finally we start our request, and run the main loop:
*
* @until return 0
* @until }
*
* The rest of this code was just freeing resources, with some labels to be used
* for error handling.
*/
/**
* @page ecore_con_url_cookies_example_c Ecore_Con_Url - Managing cookies
*
* This example shows how to use an @ref Ecore_Con_Url and enable it to
* receive/send cookies. These cookies can be set by the server, saved to a
* file, loaded later from this file and sent again to the server. The complete
* example can be found at @ref ecore_con_url_cookies_example.c
* "ecore_con_url_cookies_example.c"
*
* First we are setting some callbacks for events that will be sent when data
* arrives in our connection (the data is the content of the file being
* downloaded), and when the download is completed. The @c _url_data_cb and
* @c _url_complete_cb are these callbacks:
*
* @dontinclude ecore_con_url_download_example.c
* @skip Eina_Bool
* @until main_loop_quit
* @until }
*
* In the @c main function we parse some parameter from the command line. These
* parameters are the url that we are connecting to, and cookie use policy.
*
* After that we initialize the libraries and create a handler to our request
* using the given url:
*
* @until goto end
* @until }
*
* We also set the event handlers for this request and add a header to it, that
* will inform our custom user agent:
*
* @until User-Agent
*
* Now we start playing with cookies. First, let's call
* ecore_con_url_cookies_init() to inform that we want cookies enabled. We also
* set a file from which we are loading previously set (old) cookies, in case
* that we don't want to clear old cookies or old session cookies.
*
* After that we set the file where we are going to save all valid cookies in
* the @ref Ecore_Con_Url object. This includes previously loaded cookies (that
* weren't cleared) and new cookies set by the response header "Set-Cookie" that
* comes with the response to our request:
*
* @until jar_file_set
*
* And finally, before performing the request, we check the command passed as
* argument in the command line and use it to choose between clearing old
* cookies, clearing just old session cookies, or ignoring old session cookies.
*
* After that we just finish our code as expected:
*
* @until return
* @until }
*
* Notice that in this code, if we want to clear old cookies, we also don't load
* them from the file. This is a bit confusing and the API isn't clear, but
* ecore_con_url_cookies_file_add() will load cookies from the specified files
* just when the operation is really performed (i.e. ecore_con_url_get() is
* called). So if ecore_con_url_cookies_clear() is called before
* ecore_con_url_get(), the old cookies may not have been loaded yet, so they
* are not cleared. To avoid having old cookies loaded, don't add any cookie
* file with ecore_con_url_cookies_file_add().
*
* The function ecore_con_url_cookies_clear() is just useful to clear cookies
* that are already loaded/valid in the @ref Ecore_Con_Url object (from a
* previous request, for example).
*/
/**
* @page ecore_con_url_headers_example_c Ecore_Con_Url - customizing a request
*
* This is a simple example that shows how to make a custom request using @ref
* Ecore_Con_Url. The full source code for this example can be found at @ref
* ecore_con_url_headers_example.c.
*
* The first part of the example is setting the callbacks to be called when an
* #ECORE_CON_EVENT_URL_DATA or #ECORE_CON_EVENT_URL_COMPLETE event is received.
* These are the callbacks that are going to be used with this:
*
* @dontinclude ecore_con_url_headers_example.c
* @skip static
* @until main_loop_quit
* @until }
*
* The @c main code is as simple as the @ref Ecore_Con_Url example. It contains
* some checks for the arguments to see if a GET or POST request is required:
*
* @until GET
* @until }
*
* Then we start our required libraries and configure a global option to use
* pipelined requests:
*
* @until pipeline_set
*
* Now we create our request object, but using ecore_con_url_custom_new() to use
* a POST or GET method depending on the command line arguments. And we also add
* the event handlers for our callbacks:
*
* @until complete_cb
*
* In order to demonstrate our API, some options are set to this request before
* actually performing it:
*
* @until url_time
*
* Depending on what kind of request was asked (GET or POST), we use one of the
* specific functions to perform it:
*
* @until url_post
*
* After that, we just check for errors, start the main loop, free resources and
* finally exit:
*
* @until return
* @until }
*/
/**
* @page ecore_con_server_simple_example_c Ecore_Con - Creating a server
*
* In this example we are going to create a server that listens for connections
* from clients through a TCP port. You can get the full source code at @ref
* ecore_con_server_simple_example.c.
*
* We begin our example in the main function, to demonstrate how to setup
* things, and then go to the callbacks that are needed for it to run properly.
*
* In the @c main function, after initializing the libraries, we use
* ecore_con_server_add() to startup the server. Look at the reference
* documentation of this function: it supports many types of server, and we are
* going to use #ECORE_CON_REMOTE_TCP (a TCP based server). Other arguments to
* this function are the address where we are listening on, the port, and a data
* pointer that will associate that data with the server:
*
* @dontinclude ecore_con_server_simple_example.c
* @skip main(void)
* @until exit
*
* Notice that we are listening only on 127.0.0.1, which is the internal
* loopback interface. If the server needs to listening on all of its ips, use
* 0.0.0.0 instead.
*
* We also need to set event handlers to be called when we receive any data from
* the clients, when a new client connects to our server, or when a client
* disconnects. These callbacks are:
*
* @until CLIENT_DATA
*
* More details about what these callbacks do will be given later.
*
* Now, before running the main loop, we also want to set some limits to our
* server. To avoid it to be overloaded with too many connections to handle, we
* are going to set a maximum of 3 clients connected at the same time. This
* number is used just to demonstrate the API. A good number to be used here
* would need to be determined by tests done on the server, to check the load
* supported by it.
*
* Any other client trying to connect to this server, after the limit is
* reached, will wait until one of the connected clients disconnect and the
* server accepts the new connection.
*
* Another important thing to do is setting a timeout, to avoid that a client
* hold a connection for too long without doing anything. This timeout will
* disconnect the idle client, allowing that other clients that may be waiting
* to connect finally can do it.
*
* Then we just start the main loop:
*
* @until main_loop_begin
*
* After exiting the main loop, we print the list of connected clients, and also
* free the data associated with each respective client. This data was
* previously associated using ecore_con_client_data_set():
*
* @until }
*
* Then before exiting we show the total uptime of the server:
*
* @until uptime
*
* Now let's go back to the used callbacks.
*
* The first callback, @c _add, is registered to the event
* #ECORE_CON_EVENT_CLIENT_ADD, which will be called whenever a client connects
* to the server.
*
* This callback will associate a data structure to this client, that will be
* used to count how many bytes were received from it. It also prints some info
* about the client, and send a welcome string to it. ecore_con_client_flush()
* is used to ensure that the string is sent immediately, instead of being
* buffered.
*
* A timeout for idle specific for this client is also set, to demonstrate that
* it is independent of the general timeout of the server.
*
* Before exiting, the callback will display a list of all clients still
* connected to this server. The code for this callback follows:
*
* @dontinclude ecore_con_server_simple_example.c
* @skip Eina_Bool
* @until CALLBACK_RENEW
* @until }
*
* The second callback is @c _del. It is associated with
* #ECORE_CON_EVENT_CLIENT_DEL, and is called whenever a client disconnects from
* this server.
*
* It will just print some information about the client, free the associated
* data structure, and call ecore_con_client_del() on it before exiting the
* callback. Here's its code:
*
* @until CALLBACK_RENEW
* @until }
*
* The last callback will print any data received by this server from its
* clients. It also increments the "bytes received" counter, sdata, in the
* data structure associated with this client. The callback code follows:
*
* @until CALLBACK_RENEW
* @until }
*
* The important parts of this example were described above. If you need to see
* the full source code for it, there's a link to the code in the beginning of
* this page.
*
* This example will start a server and start accepting connections from clients, as
* demonstrated in the following diagram:
* @htmlonly
* <img src="ecore_con-client-server-example.png" style="max-width: 400px"/>
* <a href="ecore_con-client-server-example.png">Full size</a>
* @endhtmlonly
*
* @image rtf ecore_con-client-server-example.png
* @image latex ecore_con-client-server-example.eps width=\textwidth
*
* @note This example contains a serious security flaw: it doesn't check for the
* size of data being received, thus allowing to the string to be exploited in
* some way. However, it is left like this to make the code simpler and just
* demonstrate the API usage.
*/
/**
* @page ecore_con_client_simple_example_c Ecore_Con - Creating a client
*
* Following the same idea as the @ref ecore_con_server_simple_example_c , this
* example will demonstrate how to create a client that connects to a specified
* server through a TCP port. You can see the full source code at @ref
* ecore_con_client_simple_example.c.
*
* Starting from the @c main function, after reading the command line argument
* list and initializing the libraries, we try to connect to the server:
*
* @dontinclude ecore_con_client_simple_example.c
* @skip main(
* @until exit(2)
* @until }
*
* After doing this, everything else in @c main is setting up callbacks for the
* client events, starting the main loop and shutting down the libraries after
* it.
*
* Now let's go to the callbacks. These callbacks are very similar to the server
* callbacks (our implementation for this example is very simple). On the
* @c _add callback, we just set a data structure to the server, print some
* information about the server, and send a welcome message to it:
*
* @dontinclude ecore_con_client_simple_example.c
* @skip Eina_Bool
* @until CALLBACK_RENEW
* @until }
*
* The @c _del callback is as simple as the previous one. We free the data
* associated with the server, print the uptime of this client, and quit the
* main loop (since there's nothing to do once we disconnect):
*
* @until CALLBACK_RENEW
* @until }
*
* The @c _data callback is also similar to the server data callback. it will
* print any received data, and increase the data counter in the structure
* associated with this server:
*
* @skip Eina_Bool
* @until CALLBACK_RENEW
* @until }
*
* You can see the server counterpart functions of the ones used in this example
* in the @ref ecore_con_server_simple_example_c.
*
* This example will connect to the server and start comunicating with it, as
* demonstrated in the following diagram:
* @htmlonly
* <img src="ecore_con-client-server-example2.png" style="max-width: 400px"/>
* <a href="ecore_con-client-server-example2.png">Full size</a>
* @endhtmlonly
*
* @image rtf ecore_con-client-server-example2.png
* @image latex ecore_con-client-server-example2.eps width=\textwidth
*
* @note This example contains a serious security flaw: it doesn't check for the
* size of data being received, thus allowing to the string to be exploited in
* some way. However, it is left like this to make the code simpler and just
* demonstrate the API usage.
*/
/**
* @example ecore_idler_example.c
* This example shows when @ref Ecore_Idler, @ref Ecore_Idle_Enterer and @ref
* Ecore_Idle_Exiter are called. See
* @ref ecore_idler_example_c "the explanation here".
*/
/**
* @example ecore_job_example.c
* This example shows how to use an @ref Ecore_Job. See
* @ref ecore_job_example_c "the explanation here".
*/
/**
* @example ecore_time_functions_example.c
* Shows the difference between the three time functions. See @ref
* ecore_time_functions_example_c "the example explained".
*/
/**
* @example ecore_timer_example.c
* This example shows how to use timers to have timed events inside ecore.
* See @ref ecore_timer_example_c "the example explained".
*/
/**
* @example ecore_exe_example_child.c
* This is a child process used to receive messages and send it back
* to its father.
* Check the @ref Ecore_exe_simple_example_c "Full tutorial"
*/
/**
* @example ecore_exe_example.c
* This is a process that will send messages to a child and it will stop
* when it receives "quit".
* Check the @ref Ecore_exe_simple_example_c "Full tutorial"
*/
/**
* @example ecore_fd_handler_example.c
* This example shows how to setup and use an fd_handler. See
* @ref ecore_fd_handler_example_c "the explanation here".
*/
/**
* @example ecore_poller_example.c
* This example shows how to setup and use a poller. See
* @ref ecore_poller_example_c "the explanation here".
*/
/**
* @example ecore_event_example_01.c
* This example shows how to create an event handler. Explanation: @ref
* ecore_event_example_01_c
*/
/**
* @example ecore_event_example_02.c
* This example shows how to setup, change, and delete event handlers. See
* @ref ecore_event_example_02_c "the explanation here".
*/
/**
* @example ecore_fd_handler_gnutls_example.c
* Shows how to use fd handlers.
*/
/**
* @example ecore_con_lookup_example.c
* Shows how to make a simple DNS lookup. See the complete example description
* at @ref ecore_con_lookup_example_c
*/
/**
* @example ecore_con_url_download_example.c
* Shows how to download a file using an @ref Ecore_Con_Url object. See the
* complete example description at @ref ecore_con_url_download_example_c
*/
/**
* @example ecore_con_url_cookies_example.c
* Shows how to manage cookies on a @ref Ecore_Con_Url object. See the complete
* example description at @ref ecore_con_url_cookies_example_c.
*/
/**
* @example ecore_con_server_simple_example.c
* Shows how to setup a simple server that accepts client connections and sends
* a "hello" string to them. See the complete example description at @ref
* ecore_con_server_simple_example_c
*/
/**
* @example ecore_con_client_simple_example.c
* Shows how to setup a simple client that connects to a server and sends a
* "hello" string to it. See the complete example description at @ref
* ecore_con_client_simple_example_c
*/
/**
* @example ecore_con_url_headers_example.c
* Shows how to make GET or POST requests using an @ref Ecore_Con_Url object,
* and make use of most of its API. See the complete example description at
* @ref ecore_con_url_headers_example_c
*/
/**
* @page tutorial_ecore_pipe_gstreamer_example
*
* Here is an example that uses the pipe wrapper with a Gstreamer
* pipeline. For each decoded frame in the Gstreamer thread, a handle
* is called in the ecore thread.
*
* @include ecore_pipe_gstreamer_example.c
* @example ecore_pipe_gstreamer_example.c
*/
/**
* @page tutorial_ecore_pipe_simple_example
* @dontinclude ecore_pipe_simple_example.c
*
* This example shows some simple usage of ecore_pipe. We are going to create a
* pipe, fork our process, and then the child is going to communicate to the
* parent the result of its processing through the pipe.
*
* As always we start with our includes, nothing special:
* @skip #include
* @until Ecore.h
*
* The first thing we are going to define in our example is the function we are
* going to run on the child process, which, as mentioned, will do some
* processing and then will write the result to the pipe:
* @until }
* @until }
* @note The sleep was added so the parent process would think the child process
* was doing something interesting...
*
* Next up is our function for handling data arriving in the pipe. It copies the
* data to another buffer, adds a terminating NULL and prints it. Also if it
* receives a certain string it stops the main loop(effectively ending the
* program):
* @until }
* @until }
*
* And now on to our main function, we start by declaring some variables and
* initializing ecore:
* @until ecore_init
*
* And since we are talking about pipes let's create one:
* @until pipe_add
*
* Now we are going to fork:
* @until fork
* @note duh...
*
* The child process is going to do the our fancy processing:
* @until }
* @note It's very important to call ecore_pipe_read_close() here so that the
* child process won't read what it is writing to the pipe itself.
*
* And the parent is going to run ecore's main loop waiting for some data:
* @until }
* @note Calling ecore_pipe_write_close() here isn't important but since we
* aren't going to write in the pipe it is good practice.
*
* And finally when done processing(the child) or done receiving(the parent) we
* delete the pipe and shutdown ecore:
* @until }
*
* @example ecore_pipe_simple_example.c
*/
/**
* @page tutorial_ecore_animator Ecore animator example
* @dontinclude ecore_animator_example.c
*
* For this example we are going to animate a rectangle growing, moving and
* changing color, and then move it back to it's initial state with a
* different animation. We are also going to have a second rectangle moving
* along the bottom of the screen. To do this we are going to use ecore_evas,
* but since that is not the focus here we won't going into detail about it.
*
* @skip #include
* @until evas_object_show
* @until evas_object_show
* All of this is just setup, not what we're interested in right now.
*
* Now we are going to set the frametime for our animation to one fiftieth of
* a second, this will make our program consume more resources but should make
* our animation extra smooth:
* @until frametime
*
* And now we get right to the business of creating our ecore_animator:
* @until timeline
* @note We are telling our animation to last 10 second and to call
* _advance_frame with rect as data.
*
* So far we setup the first and second animations, the third one however is a
* bit different, this time we won't use a timeline animation, that's because we
* don't want our animation to stop:
* @until animator_add
*
* Next we set a few timers to execute _start_second_anim, _freeze_third_anim
* and _thaw_thir_anim in 10, 5 and 10 seconds respectively:
* @until thaw
*
* And now we tell ecore to begin the main loop and free some resources once
* it leaves the main loop:
* @until }
*
* Here we have the callback function for our first animation, which first
* takes @p pos(where in the timeline we are), maps it to a SPRING curve that
* which will wobble 15 times and will decay by a factor of 1.2:
* @until pos_map
*
* Now that we have the frame we can adjust the rectangle to its appropriate
* state:
* @until }
*
* And now the callback that will run 10 seconds after the program starts(5
* seconds after the first animation finishes) and starts our second
* animation:
* @until }
* @note For this animation we made the frametime much larger which means our
* animation might get "jerky".
*
* The callback for our second animation, our savvy reader no doubt noted that
* it's very similar to the callback for the first animation. What we change for
* this one is the type of animation to BOUNCE and the number of times it will
* bounce to 50:
* @until }
*
* And for our last animation callback something simpler, we just move our
* rectangle right by one pixel until it reaches the end of the screen and then
* start at the beginning again:
* @until }
*
* Our next two functions respectively freezes and thaw our third animation, so
* that it won't happen for the 5 seconds after the first animation ends and the
* second animation begins:
* @until }
* @until }
*
* @example ecore_animator_example.c
*/
/**
* @page ecore_thread_example_c Ecore_Thread - API overview
*
* Working with threads is hard. Ecore helps to do so a bit easier, but as
* the example in @ref ecore_thread_example.c "ecore_thread_example.c" shows,
* there's a lot to consider even when doing the most simple things.
*
* We'll be going through this thorough example now, showing how the differents
* aspects of @ref Ecore_Thread are used, but users are encourage to avoid
* threads unless it's really the only option, as they always add more
* complexity than the program usually requires.
*
* Ecore Threads come in two flavors, short jobs and feedback jobs. Short jobs
* just run the given function and are more commonly used for small tasks
* where the main loop does not need to know how the work is going in between.
* The short job in our example is so short we had to artificially enlarge it
* with @c sleep(). Other than that, it also uses threads local data to keep
* the data we are working with persistent across different jobs ran by the
* same system thread. This data will be freed when the no more jobs are
* pending and the thread is terminated. If the data doesn't exist in the
* thread's storage, we create it and save it there for future jobs to find
* it. If creation fails, we cancel ourselves, so the main loop knows that
* we didn't just exit normally, meaning the job could not be done. The main
* part of the function checks in each iteration if it was canceled by the
* main loop, and if it was, it stops processing and clears the data from the
* storage (we assume @c cancel means no one else will need this, but this is
* really application dependent).
* @dontinclude ecore_thread_example.c
* @skip static void
* @until sleep(1)
* @until }
* @until }
*
* Feedback jobs, on the other hand, run tasks that will inform back to the
* main loop its progress, send partial data as is processed, just ping saying
* it's still alive and processing, or anything that needs the thread to talk
* back to the main loop.
* @skip static void
* @until the_end
* @until }
*
* Finally, one more feedback job, but this one will be running outside of
* Ecore's pool, so we can use the pool for real work and keep this very
* light function unchecked. All it does is check if some condition is met
* and send a message to the main loop telling it it's time to close.
* @skip static void
* @until }
* @until }
* @until }
*
* Every now and then the program prints its status, counting threads running
* and pending jobs.
* @skip static void
* @until }
*
* In our main loop, we'll be receiving messages from our feedback jobs using
* the same callback for both of them.
* @skip static void
* @until char *str
*
* The light job running out of the pool will let us know when we can exit our
* program.
* @until }
*
* Next comes the handling of data sent from the actual worker threads, always
* remembering that the data belongs to us now, and not the thread, so it's
* our responsibility to free it.
* @until }
* @until }
*
* Last, the condition to exit is given by how many messages we want to handle,
* so we need to count them and inform the condition checking thread that the
* value changed.
* @until }
*
* When a thread finishes its job or gets canceled, the main loop is notified
* through the callbacks set when creating the task. In this case, we just
* print what happen and keep track of one of them used to exemplify canceling.
* Here we are pretending one of our short jobs has a timeout, so if it doesn't
* finish before a timer is triggered, it will be canceled.
* @skip static void
* @until _cancel_timer_cb
* @until }
*
* The main function does some setup that includes reading parameters from
* the command line to change its behaviour and test different results.
* These are:
* @li -t \<some_num\> maximum number of threads to run at the same time.
* @li -p \<some_path\> adds @c some_path to the list used by the feedback jobs.
* This parameter can be used multiple times.
* @li -m \<some_num\> the number of messages to process before the program is
* signalled to exit.
*
* Skipping some bits, we init Ecore and our application data.
* @skip ecore_init
* @until appdata.max_msgs
*
* If any paths for the feedback jobs were given, we use them, otherwise we
* fallback to some defaults. Always initializing the proper mutexes used by the
* threaded job.
* @skip path_list
* @until EINA_LIST_FREE
* @until }
* @until }
*
* Initialize the mutex needed for the condition checking thread
* @skip appdata.mutex
* @until appdata.condition
*
* And start our tasks.
* @until appdata.thread_3
* @until EINA_FALSE
*
* To finalize, set a timer to cancel one of the tasks if it doesn't end
* before the timeout, one more timer for status report and get into the main
* loop. Once we are out, destroy our mutexes and finish the program.
* @until _status_timer_cb
* @until }
*
* @example ecore_thread_example.c
*/
/**
* @page ecore_evas_callbacks_example_c Ecore Evas Callbacks
* @dontinclude ecore_evas_callbacks.c
*
* Our example is remarkably simple, all it does is create an Ecore_Evas and
* register a callback for a bunch of events. What's interesting here is
* knowing when each of these callbacks will be called, however since that
* depends on the underlying windowing system there are no guarantees that all
* of the callbacks will be called for your windowing system. To know which
* callbacks will be called for your windowing system run the example and
* redirect the output to a file, and take a look at it.
*
* @note Make sure you minimize, resize, give and remove focus to see more
* callbacks called.
*
* The example is constituted of two main parts, first is the implementation of
* callbacks that will be called for each event(all our callbacks do is print
* their own name) and the second is the main function where we register the
* event callbacks and run the main loop:
* @include ecore_evas_callbacks.c
* @example ecore_evas_callbacks.c
*/
/**
* @page Ecore_Evas_Window_Sizes_Example_c Ecore_Evas window size hints
*
* On this example, we show you how to deal with @c Ecore_Evas window
* size hints, which are implemented <b>per Evas engine</b>.
*
* We start by defining an initial size for our window and, after
* creating it, adding a background white rectangle and a text object
* to it, to be used to display the current window's sizes, at any
* given time:
* @dontinclude ecore_evas_window_sizes_example.c
* @skip define WIDTH
* @until define
* @until define
* @dontinclude ecore_evas_window_sizes_example.c
* @skip evas_init
* @until show(bg)
* @dontinclude ecore_evas_window_sizes_example.c
* @skip text =
* @until main_loop_begin
* @dontinclude ecore_evas_window_sizes_example.c
* @skip to inform
* @until }
*
* The program has a command line interface, responding to the
* following keys:
* @dontinclude ecore_evas_window_sizes_example.c
* @skip commands
* @until ;
*
* Use the @c 'm' key to impose a minimum size of half the initial
* ones on our window. Test it by trying to resize it to smaller sizes
* than that:
* @dontinclude ecore_evas_window_sizes_example.c
* @skip key, "m"
* @until }
* @until }
* @until }
*
* The @c 'x' key will, in turn, set a maximum size on our window --
* to two times our initial size. Test it by trying to resize the
* window to bigger sizes than that:
* @dontinclude ecore_evas_window_sizes_example.c
* @skip key, "x"
* @until }
* @until }
* @until }
*
* Window base sizes will override any minimum sizes set, so try it
* with the @c 'b' key. It will set a base size of two times the
* initial one:
* @dontinclude ecore_evas_window_sizes_example.c
* @skip key, "b"
* @until }
* @until }
* @until }
*
* Finally, there's a key to impose a "step size" on our window, of 40
* pixels. With than on (@c 's' key), you'll see the window will
* always be bound to @b multiples of that size, for dimensions on
* both axis:
* @skip key, "s"
* @until }
* @until }
* @until }
*
* The full example follows.
*
* @include ecore_evas_window_sizes_example.c
* @example ecore_evas_window_sizes_example.c
*/
/**
* @page ecore_evas_object_example_c Ecore Evas Object example
* @dontinclude ecore_evas_object_example.c
*
* This example creates an Ecore_Evas(a window) and associates a background and
* a custom cursor for it.
*
* We'll start looking at the association, which is quite simple. We choose to
* associate using ECORE_EVAS_OBJECT_ASSOCIATE_BASE to have it be resized with
* the window, since for a background that is what's most useful:
* @skipline ecore_evas_object_associate
* @note If we didn't associate the background we'd need to listen to resize of
* Ecore_Evas and manually resize the background or have artifacts on our
* window.
*
* We then check that the association worked:
* @until printf
*
* Next we are going to set a custom cursor, for our cursor we are going to use
* a small green rectangle. Our cursor is going to be on layer 0(any lower and
* it would be below the background and thus invisible) and clicks will be
* computed as happening on pixel 1, 1 of the image:
* @until cursor_set
*
* We then check every one of those parameters:
* @until printf
*
* Here you have the full-source of the code:
* @include ecore_evas_object_example.c
* @example ecore_evas_object_example.c
*/
/**
* @page ecore_evas_basics_example_c Ecore Evas basics example
* @dontinclude ecore_evas_basics_example.c
*
* This example will illustrates the usage of some basic Ecore_Evas functions.
* This example will list the available evas engines, check which one we used to
* create our window and set some data on our Ecore_Evas. It also allows you to
* hide/show all windows in this process(we only have one, but if there were
* more they would be hidden), to hide the windows type 'h' and hit return, to
* show them, type 's' and hit return.
*
* The very first thing we'll do is initialize ecore_evas:
* @skipline evas_init
* @until return 1
*
* Once inited we query which engines are available:
* @until ecore_evas_engines_free
*
* We then create an Ecore_Evas(window) with the first available engine, on
* position 0,0 with size 200,200 and no especial flags, set it's title and show
* it:
* @until evas_show
*
* We now add some important data to our Ecore_Evas:
* @until data_set
*
* And since our data is dynamically allocated we'll need to free it when the
* Ecore_Evas dies:
* @until delete_request
* @dontinclude ecore_evas_basics_example.c
* @skip static void
* @until }
* @skip printf("Using
*
* We now print which Evas engine is being used for our example:
* @until printf
*
* We are going to add a background to our window but before we can do that
* we'll need to get the canvas(Evas) on which to draw it:
* @until canvas
*
* We then do a sanity check, verifying if the Ecore_Evas of the Evas is the
* Ecore_Evas from which we got the Evas:
* @until printf
*
* Now we can actually add the background:
* @until ecore_evas_object_associate
*
* To hide and show the windows of this process when the user presses 'h' and
* 's' respectively we need to know when the user types something, so we
* register a callback for when we can read something from @c stdin:
* @until )
*
* The callback that actually does the hiding and showing is pretty simple, it
* does a @c scanf(which we know won't block since there is something to read on
* @c stdin) and if the character is an 'h' we iterate over all windows calling
* @c ecore_evas_hide on them, if the character is an 's' we call @c
* ecore_evas_show instead:
* @dontinclude ecore_evas_basics_example.c
* @skip static Eina_Bool
* @until }
* @skip ecore_main_loop_begin
*
* Once all is done we run our main loop, and when that is done(application is
* exiting) we free our Ecore_Evas and shutdown the ecore_evas subsystem:
* @until shutdown
*
* Here you have the full-source of the code:
* @include ecore_evas_basics_example.c
* @example ecore_evas_basics_example.c
*/
/**
* @page Ecore_Evas_Buffer_Example_01_c Ecore_Evas buffer example
*
* Between the Evas examples, there is one in which one creates a
* canvas bound to the Evas @b buffer engine and uses its pixel
* contents to create an PPM image on disk. There, one does that by
* creating the canvas "by hand", with @c evas_new(), @c
* evas_engine_info_set(), etc.
*
* On this example, we accomplish the very same task, but by using the
* @c Ecore_Evas helper wrapper functions on a buffer engine
* canvas. If you compare both codes, you'll see how much code one is
* saved from by using the @c Ecore_Evas wrapper functions.
*
* The code is simple as it can be. After instantianting our canvas
* window, with ecore_evas_buffer_new(), we grab its canvas pointer
* and create the desired objects scene on it, which in this case is
* formed by 3 rectangles over the top left corner of a white
* background:
* @dontinclude ecore_evas_buffer_example_01.c
* @skip main(void)
* @until show(r3)
*
* Since it's a buffer canvas and we're using it to only save its
* contents on a file, we even needn't ecore_evas_show() it. We make
* it render itself, forcefully, without the aid of Ecore's main loop,
* with ecore_evas_manual_render():
* @dontinclude ecore_evas_buffer_example_01.c
* @skip manual_render
* @until manual_render
*
* And we're ready to save the window's shiny rendered contents as a
* simple PPM image. We do so by grabbing the pixels of the @c
* Ecore_Evas' internal canvas, with ecore_evas_buffer_pixels_get():
* @dontinclude ecore_evas_buffer_example_01.c
* @skip _scene_save
* @until }
* @dontinclude ecore_evas_buffer_example_01.c
* @skip support function
* @until }
* @until }
* @until }
*
* Check that destination file for the result. The full example
* follows.
*
* @include ecore_evas_buffer_example_01.c
* @example ecore_evas_buffer_example_01.c
*/
/**
* @page Ecore_Evas_Buffer_Example_02_c Ecore_Evas (image) buffer example
*
* In this example, we'll demonstrate the use of
* ecore_evas_object_image_new(). The idea is to have the same scene
* created for @ref Ecore_Evas_Buffer_Example_01_c as the contents of
* an image object.
*
* The canvas receiving this image object will have a white
* background, a red border image to delimit this image's boundaries
* and the image itself. After we create the special image, we set
* its "fill" property, place and resize it as we want. We have also
* to resize its underlying @c Ecore_Evas too, to the same dimensions:
* @dontinclude ecore_evas_buffer_example_02.c
* @skip object_image_new
* @until resize(sub_ee
*
* Now, we re-create the scene we cited, using the sub-canvas of our
* image to parent the objects in question. Because image objects are
* created with the alpha channel enabled, by default, we'll be seeing
* our white rectangle beneath the scene:
* @dontinclude ecore_evas_buffer_example_02.c
* @skip rectangle_add(sub_canvas
* @until loop_begin
*
* And that's all. The contents of our image could be updated as one
* wished, and they would always be mirrored in the image's area.
*
* Check that destination file for the result. The full example
* follows.
*
* @include ecore_evas_buffer_example_02.c
* @example ecore_evas_buffer_example_02.c
*/
/**
* @page Ecore_exe_simple_example_c Ecore_exe
* Creating a processes and IPC (Inter process communication)
*
* In this example we will show how to create a new process and communicate
* with it in a portable way using the Ecore_exe module.
*
* In this example we will have two process and both will communicate with each
* other using messages. A father process will start a child process and it will
* keep sending messages to the child until it receives a message to quit.
* To see the full source use the links:
* @li @ref ecore_exe_example.c "Father"
* @li @ref ecore_exe_example_child.c "Child"
*
* Let's start the tutorial. The implementation of the child it's pretty simple.
* We just read strings from stdin and write a message in the stdout. But you
* should be asking yourself right know. "If I'm receiving data from an other
* process why I'm reading and writing in stdin/stdout?". That's because, when
* you spawn a process using the Ecore_Exe module it will create a pipe between
* the father and the child process and the stdin/stdout of the child process
* will be redirected to the pipe. So when the child wants to receive or send
* data to the father, just use the stdin/stdout.
* However the steps to send data from the father to the child is quite
* different, but we will get there.
*
* The child will register a fd handler to monitor the stdin.
* So we start registering the ecore FD handler:
* @dontinclude ecore_exe_example_child.c
* @skip ecore_main_fd_handler_add
* @until ;
*
* If you don't remember the parameters of @ref ecore_main_fd_handler_add,
* please check its documentation.
*
* Now that we have our handler registered we will start the ecore's main loop:
* @skipline ecore_main_loop_begin
*
* Now let's take a look in the callback function. Its a simple function
* that will read from stdin 3 times and at the third time will say
* to the father: "quit".
* @dontinclude ecore_exe_example_child.c
* @skip static Eina_Bool
* @until }
* @until }
* @until }
* @until }
*
* You may notice that we are sending the messages to stdout, and our father
* will receive it. Also our string must have a "\n" because the string will
* be buffered in the pipe until it finds EOF or a "newline" in our case we
* won't have a EOF unless we close the pipe, so we use the "\n" char.
*
* One more thing, we use fflush(stdout) because probably our message won't
* fill our entire buffer and the father would never receive the message. So we
* use this function to flush the buffer and the father can receive as fast as
* possible.
*
* Now that we have our child ready, let's start our work in the father's source
* code.
*
* We start creating the child process like this:
* @dontinclude ecore_exe_example.c
* @skip childHandle = ecore_exe_pipe_run
* @until ;
*
* With the command above we are creating our child process, the first
* parameter is the command to be executed, the second are the pipe flags and
* in our case we will write and read in the pipe so we must say what we are
* doing in the pipe. You may notice the flag ECORE_EXE_PIPE_READ_LINE_BUFFERED,
* this means that reads are buffered until I find a newline. And the third
* parameter is data that we would like to send to the process in its creating.
* This case we are sending nothing, so just use NULL.
*
* Then we check if the process was created:
* @skip if
* @until }
*
* After this we get the PID of the child process and just print it in the screen.
* The PID stands for Process identification. This is just an internal
* identifier of your process:
*
* @skip childPid
* @until fprintf
* @until fprintf
*
* The way that Ecore_exe works is: when we want to read data sent from
* our child we must use an ecore event.
* So let's start register our event listener:
* @skipline ecore_event_handler_add
*
* Now to send messages to our child we will use a timer, so every 1 second we
* will send a message to the child.
* @skipline ecore_timer_add
*
* After all this we start the main loop. Now let's pass to the callback
* functions.
*
* Now we will see how we actually send the data and receive it.
* Let's start with _sendMessage:
* @dontinclude ecore_exe_example.c
* @skip _sendMessage(void *data)
* @until }
*
* We use ecore_exe_send to send data to the child process, it's pretty simple.
* To know what the parameters stands for, check the docs.
*
* @note The function @b ecore_exe_send will never block your program, also
* there is no partial send of the data. This means either the function will
* send all the data or it will fail.
*
* Now let's take a look in our event callback and see how we retrieve the
* messages.
* @dontinclude ecore_exe_example.c
* @skip static Eina_Bool
* @until }
* @until }
*
* It's just like an normal event, we get a reference to Ecore_Exe_Event_Data,
* extract the data and then show it in the screen.
*
* And that's it, after all it's not complicated to create a process and
* communicate with it.
*
*/
/**
* @page ecore_imf_example_c ecore_imf - How to handle preedit and commit string from Input Method Framework
*
* This example demonstrates how to connect input method framework and handle preedit and commit string from input method framework.
*
* To input Chinese, Japanese, Korean and other complex languages, the editor should be connected with input method framework.
*
* How to initialize and shutdown ecore imf module
* @li ecore_imf_init() should be called to initialize and load immodule.
* @li ecore_imf_shutdown() is used for shutdowning and unloading immodule.
*
* How to create input context and register pre-edit and commit event handler
*
* Each entry should have each input context to connect with input service framework.
* Key event is processed by input method engine.
* The result is notified to application through ECORE_IMF_CALLBACK_PREEDIT_CHANGED and ECORE_IMF_CALLBACK_COMMIT event.
*
* The full example follows.
*
* @include ecore_imf_example.c
*/