Use wallpaper colors for widgets in wallpaper change preview

Test: Widgets should adapt to new wallpaper colors in launcher preview.
Bug: 191499358
Change-Id: I3fb76b6036cb909771b789eac15742df78c2c742

lint-baseline-launcher3.xml

@@ -573,4 +573,15 @@
             column="42"/>
     </issue>
 
+    <issue
+        id="NewApi"
+        message="Call requires API level 31 (current min is 26): `android.appwidget.AppWidgetHostView#setColorResources`"
+        errorLine1="                setColorResources(mWallpaperColorResources);"
+        errorLine2="                ~~~~~~~~~~~~~~~~~">
+        <location
+            file="packages/apps/Launcher3/src/com/android/launcher3/graphics/LauncherPreviewRenderer.java"
+            line="528"
+            column="17"/>
+    </issue>
+
 </issues>

src/com/android/launcher3/graphics/LauncherPreviewRenderer.java

@@ -26,6 +26,7 @@ import static com.android.launcher3.model.ModelUtils.sortWorkspaceItemsSpatially
 
 import android.annotation.TargetApi;
 import android.app.Fragment;
+import android.app.WallpaperColors;
 import android.appwidget.AppWidgetHost;
 import android.appwidget.AppWidgetHostView;
 import android.appwidget.AppWidgetProviderInfo;
@@ -42,6 +43,7 @@ import android.os.Handler;
 import android.os.Looper;
 import android.os.Process;
 import android.util.AttributeSet;
+import android.util.SparseIntArray;
 import android.view.ContextThemeWrapper;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -87,6 +89,7 @@ import com.android.launcher3.views.BaseDragLayer;
 import com.android.launcher3.widget.BaseLauncherAppWidgetHostView;
 import com.android.launcher3.widget.LauncherAppWidgetHost;
 import com.android.launcher3.widget.LauncherAppWidgetProviderInfo;
+import com.android.launcher3.widget.LocalColorExtractor;
 import com.android.launcher3.widget.NavigableAppWidgetHostView;
 import com.android.launcher3.widget.custom.CustomWidgetManager;
 
@@ -206,8 +209,12 @@ public class LauncherPreviewRenderer extends ContextWrapper
     private final Hotseat mHotseat;
     private final CellLayout mWorkspace;
     private final AppWidgetHost mAppWidgetHost;
+    private final SparseIntArray mWallpaperColorResources;
+
+    public LauncherPreviewRenderer(Context context,
+            InvariantDeviceProfile idp,
+            WallpaperColors wallpaperColors) {
 
-    public LauncherPreviewRenderer(Context context, InvariantDeviceProfile idp) {
         super(context);
         mUiHandler = new Handler(Looper.getMainLooper());
         mContext = context;
@@ -260,9 +267,16 @@ public class LauncherPreviewRenderer extends ContextWrapper
                 mDp.workspacePadding.right + mDp.cellLayoutPaddingLeftRightPx,
                 mDp.workspacePadding.bottom);
 
-        mAppWidgetHost = FeatureFlags.WIDGETS_IN_LAUNCHER_PREVIEW.get()
-                ? new LauncherPreviewAppWidgetHost(context)
+        if (FeatureFlags.WIDGETS_IN_LAUNCHER_PREVIEW.get()) {
+            mAppWidgetHost = new LauncherPreviewAppWidgetHost(context);
+            mWallpaperColorResources =  wallpaperColors != null
+                    ? LocalColorExtractor.newInstance(context)
+                            .generateColorsOverride(wallpaperColors)
                     : null;
+        } else {
+            mAppWidgetHost = null;
+            mWallpaperColorResources = null;
+        }
     }
 
     /** Populate preview and render it. */
@@ -507,10 +521,12 @@ public class LauncherPreviewRenderer extends ContextWrapper
         }
     }
 
-    private static class LauncherPreviewAppWidgetHostView extends BaseLauncherAppWidgetHostView {
-
+    private class LauncherPreviewAppWidgetHostView extends BaseLauncherAppWidgetHostView {
         private LauncherPreviewAppWidgetHostView(Context context) {
             super(context);
+            if (Utilities.ATLEAST_S && mWallpaperColorResources != null) {
+                setColorResources(mWallpaperColorResources);
+            }
         }
 
         @Override

src/com/android/launcher3/graphics/PreviewSurfaceRenderer.java

@@ -209,7 +209,7 @@ public class PreviewSurfaceRenderer {
         if (mDestroyed) {
             return;
         }
-        View view = new LauncherPreviewRenderer(inflationContext, mIdp)
+        View view = new LauncherPreviewRenderer(inflationContext, mIdp, mWallpaperColors)
                 .getRenderedView(dataModel, widgetProviderInfoMap);
         // This aspect scales the view to fit in the surface and centers it
         final float scale = Math.min(mWidth / (float) view.getMeasuredWidth(),

src/com/android/launcher3/widget/LocalColorExtractor.java

@@ -75,6 +75,14 @@ public class LocalColorExtractor implements ResourceBasedOverride {
      */
     public void applyColorsOverride(Context base, WallpaperColors colors) { }
 
+    /**
+     * Generates color resource overrides from {@link WallpaperColors}.
+     */
+    @Nullable
+    public SparseIntArray generateColorsOverride(WallpaperColors colors) {
+        return null;
+    }
+
     /**
      * Takes a view and returns its rect that can be used by the wallpaper local color extractor.
      *