src/com/android/browser/DraggableFrameLayout.java

/*
 * Copyright (c) 2015, The Linux Foundation. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 *       copyright notice, this list of conditions and the following
 *       disclaimer in the documentation and/or other materials provided
 *       with the distribution.
 *     * Neither the name of The Linux Foundation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
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*/

package com.android.browser;

import android.content.Context;
import android.support.v4.view.ViewCompat;
import android.support.v4.widget.ViewDragHelper;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ViewGroup;
import android.widget.FrameLayout;

public class DraggableFrameLayout extends FrameLayout {
    private ViewDragHelper mDragger;
    public DraggableFrameLayout(Context ctx) {
        super(ctx);
    }
    public DraggableFrameLayout(Context ctx, AttributeSet set) {
        super(ctx, set);
    }
    public DraggableFrameLayout(Context ctx, AttributeSet set, int defStyleAttr) {
        super(ctx, set, defStyleAttr);
    }
    public DraggableFrameLayout(Context ctx, AttributeSet set, int defStyleAttr, int defStyleRes) {
        super(ctx, set, defStyleAttr, defStyleRes);
    }

    public void setDragHelper(ViewDragHelper dragger) {
        mDragger = dragger;
    }

    public final ViewGroup getParentViewGroup() {
        return (ViewGroup) DraggableFrameLayout.this.getParent();
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        if (mDragger == null)
            return super.onInterceptTouchEvent(event);

        return mDragger.shouldInterceptTouchEvent(event) ?
                true : super.onInterceptTouchEvent(event);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (mDragger == null)
            return super.onTouchEvent(event);

        mDragger.processTouchEvent(event);
        return true;
    }

    @Override
    public void computeScroll() {
        super.computeScroll();
        if (mDragger != null && mDragger.continueSettling(true)) {
            ViewCompat.postInvalidateOnAnimation(this);
        }
    }
}