Java tutorial
/* * 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 com.sinenco.sharednews.listviewremovalanimation; import android.content.Context; import android.graphics.Canvas; import android.graphics.drawable.Drawable; import android.support.v4.content.res.ResourcesCompat; import android.util.AttributeSet; import android.widget.FrameLayout; import com.sinenco.sharednews.R; public class BackgroundContainer extends FrameLayout { boolean mShowing = false; Drawable mShadowedBackground; int mOpenAreaTop, mOpenAreaBottom, mOpenAreaHeight; boolean mUpdateBounds = false; public BackgroundContainer(Context context) { super(context); init(); } public BackgroundContainer(Context context, AttributeSet attrs) { super(context, attrs); init(); } public BackgroundContainer(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(); } private void init() { mShadowedBackground = ResourcesCompat.getDrawable(getResources(), R.drawable.shadowed_background, null); } public void showBackground(int top, int bottom) { setWillNotDraw(false); mOpenAreaTop = top; mOpenAreaHeight = bottom; mShowing = true; mUpdateBounds = true; } public void hideBackground() { setWillNotDraw(true); mShowing = false; } @Override protected void onDraw(Canvas canvas) { if (mShowing) { if (mUpdateBounds) { mShadowedBackground.setBounds(0, 0, getWidth(), mOpenAreaHeight); } canvas.save(); canvas.translate(0, mOpenAreaTop); mShadowedBackground.draw(canvas); canvas.restore(); } } }