/* * 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.example.android.bouncer; import android.animation.ValueAnimator; import android.animation.ValueAnimator.AnimatorUpdateListener; import android.app.Activity; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Paint; import android.os.Bundle; import android.util.AttributeSet; import android.view.View; import android.view.animation.AccelerateInterpolator; /** * See the comments in Bouncer for the overall functionality of this app. Changes for this * variation are down in the animation setup code. */ public class Bouncer2 extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_bouncer2); } static class MyView extends View { Bitmap mBitmap; Paint paint = new Paint(); int mShapeX, mShapeY; int mShapeW, mShapeH; public MyView(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); setupShape(); } public MyView(Context context, AttributeSet attrs) { super(context, attrs); setupShape(); } public MyView(Context context) { super(context); setupShape(); } public void setShapeX(int shapeX) { int minX = mShapeX; int maxX = mShapeX + mShapeW; mShapeX = shapeX; minX = Math.min(mShapeX, minX); maxX = Math.max(mShapeX + mShapeW, maxX); invalidate(minX, mShapeY, maxX, mShapeY + mShapeH); } public void setShapeY(int shapeY) { int minY = mShapeY; int maxY = mShapeY + mShapeH; mShapeY = shapeY; minY = Math.min(mShapeY, minY); maxY = Math.max(mShapeY + mShapeH, maxY); invalidate(mShapeX, minY, mShapeX + mShapeW, maxY); } private void setupShape() { mBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.electricsheep); mShapeW = mBitmap.getWidth(); mShapeH = mBitmap.getHeight(); setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { startAnimation(); } }); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { mShapeX = (w - mBitmap.getWidth()) / 2; mShapeY = 0; } @Override protected void onDraw(Canvas canvas) { canvas.drawBitmap(mBitmap, mShapeX, mShapeY, paint); } void startAnimation() { ValueAnimator anim = getValueAnimator(); anim.setRepeatCount(ValueAnimator.INFINITE); anim.setRepeatMode(ValueAnimator.REVERSE); // This variation finally has the shape bouncing, due to the use of an // AccelerateInterpolator, which speeds up as the animation proceed. Note that // when the animation reverses, the interpolator acts in reverse, decelerating // movement. anim.setInterpolator(new AccelerateInterpolator()); anim.start(); } ValueAnimator getValueAnimator() { ValueAnimator anim = ValueAnimator.ofFloat(0, 1); anim.addUpdateListener(new AnimatorUpdateListener() { @Override public void onAnimationUpdate(ValueAnimator animation) { setShapeY((int) (animation.getAnimatedFraction() * (getHeight() - mShapeH))); } }); return anim; } } }