| /* |
| * Copyright (C) 2013 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package android.view; |
| |
| import android.graphics.drawable.Drawable; |
| |
| /** |
| * An overlay is an extra layer that sits on top of a View (the "host view") which is drawn after |
| * all other content in that view (including children, if the view is a ViewGroup). Interaction |
| * with the overlay layer is done in terms of adding/removing views and drawables. Invalidation and |
| * redrawing of the overlay layer (and its host view) is handled differently for views versus |
| * drawables in the overlay. Views invalidate themselves as usual, causing appropriate redrawing |
| * to occur automatically. Drawables, on the other hand, do not manage invalidation, so changes to |
| * drawable objects should be accompanied by appropriate calls to invalidate() on the host view. |
| * |
| * @see android.view.View#getOverlay() |
| */ |
| public interface Overlay { |
| |
| /** |
| * Adds a Drawable to the overlay. The bounds of the drawable should be relative to |
| * the host view. Any drawable added to the overlay should be removed when it is no longer |
| * needed or no longer visible. There is no automatic invalidation of the host view; changes to |
| * the drawable should be accompanied by appropriate invalidation calls to the host view |
| * to cause the proper area of the view, and the overlay, to be redrawn. |
| * |
| * @param drawable The Drawable to be added to the overlay. This drawable will be |
| * drawn when the view redraws its overlay. |
| * @see #remove(android.graphics.drawable.Drawable) |
| * @see #add(View) |
| */ |
| void add(Drawable drawable); |
| |
| /** |
| * Removes the specified Drawable from the overlay. |
| * |
| * @param drawable The Drawable to be removed from the overlay. |
| * @see #add(android.graphics.drawable.Drawable) |
| */ |
| void remove(Drawable drawable); |
| |
| /** |
| * Adds a View to the overlay. The bounds of the added view should be relative to |
| * the host view. Any view added to the overlay should be removed when it is no longer |
| * needed or no longer visible. The view must not be parented elsewhere when it is added |
| * to the overlay. |
| * |
| * @param view The View to be added to the overlay. The added view will be |
| * drawn when the overlay is drawn. |
| * @see #remove(View) |
| * @see #add(android.graphics.drawable.Drawable) |
| */ |
| void add(View view); |
| |
| /** |
| * Removes the specified View from the overlay. |
| * |
| * @param view The View to be removed from the overlay. |
| * @see #add(View) |
| */ |
| void remove(View view); |
| |
| /** |
| * Removes all views and drawables from the overlay. |
| */ |
| void clear(); |
| } |