transition/ics/android/support/transition/ViewGroupOverlay.java

/*
 * Copyright (C) 2016 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.support.transition;

import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.drawable.Drawable;
import android.support.annotation.RequiresApi;
import android.view.View;
import android.view.ViewGroup;

@RequiresApi(14)
@TargetApi(14)
class ViewGroupOverlay extends ViewOverlay {

    ViewGroupOverlay(Context context, ViewGroup hostView, View requestingView) {
        super(context, hostView, requestingView);
    }

    public static ViewGroupOverlay createFrom(ViewGroup viewGroup) {
        return (ViewGroupOverlay) ViewOverlay.createFrom(viewGroup);
    }

    /**
     * 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.
     *
     * <p>Views in the overlay are visual-only; they do not receive input
     * events and do not participate in focus traversal. Overlay views
     * are intended to be transient, such as might be needed by a temporary
     * animation effect.</p>
     *
     * <p>If the view has a parent, the view will be removed from that parent
     * before being added to the overlay. Also, if that parent is attached
     * in the current view hierarchy, the view will be repositioned
     * such that it is in the same relative location inside the activity. For
     * example, if the view's current parent lies 100 pixels to the right
     * and 200 pixels down from the origin of the overlay's
     * host view, then the view will be offset by (100, 200).</p>
     *
     * @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 android.view.ViewOverlay#add(Drawable)
     */
    public void add(View view) {
        mOverlayViewGroup.add(view);
    }

    /**
     * Removes the specified View from the overlay.
     *
     * @param view The View to be removed from the overlay.
     * @see #add(View)
     * @see android.view.ViewOverlay#remove(Drawable)
     */
    public void remove(View view) {
        mOverlayViewGroup.remove(view);
    }
}