自定义view渐变背景，同时监听手势自动生成小圆球。
宿主Activity如下：
package com.edaixi.tempbak;
import java.util.ArrayList;
import android.animation.Animator;
import android.animation.AnimatorListenerAdapter;
import android.animation.AnimatorSet;
import android.animation.ArgbEvaluator;
import android.animation.ObjectAnimator;
import android.animation.ValueAnimator;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.RadialGradient;
import android.graphics.Shader;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.OvalShape;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.Window;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.DecelerateInterpolator;
import android.widget.LinearLayout;
@SuppressLint("NewApi")
public class MainActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
LinearLayout container = (LinearLayout) findViewById(R.id.container);
container.addView(new MyAnimationView(this));
}
public class MyAnimationView extends View {
private static final int RED = 0xffFF8080;
private static final int BLUE = 0xff8080FF;
private static final int CYAN = 0xff80ffff;
private static final int GREEN = 0xff80ff80;
public final ArrayList<ShapeHolder> balls = new ArrayList<ShapeHolder>();
AnimatorSet animation = null;
public MyAnimationView(Context context) {
super(context);
/**************************************************************************************************
*
* 设置自定义view的背景，是一个渐变的过程，用ValueAnimator实现，ValueAnimator是Property
* Animation系统 的核心类，它包含了配置Property Animation属性的大部分方法，那要实现一个Property
* Animation,都需要直接 或间接使用ValueAnimator类，使用ValueAnimator的步骤如下：
* 1.调用ValueAnimation类中的ofInt(int...values)、ofFloat(String
* propertyName,float...values)等静态方
* 法实例化ValueAnimator对象，并设置目标属性的属性名、初始值或结束值等值;
* 2.调用addUpdateListener(AnimatorUpdateListener
* mListener)方法为ValueAnimator对象设置属性变化的监听器
* 3.创建自定义的Interpolator，调用setInterpolator(TimeInterpolator
* value)为ValueAniamtor设置自定义的 Interpolator;(可选，不设置默认为缺省值)
* 4.创建自定义的TypeEvaluator,调用setEvaluator(TypeEvaluator
* value)为ValueAnimator设置自定义的 TypeEvaluator;(可选，不设置默认为缺省值)
* 5.在AnimatorUpdateListener 中的实现方法为目标对象的属性设置计算好的属性值。
* 6.设置动画的持续时间、是否重复及重复次数等属性; 7.为ValueAnimator设置目标对象并开始执行动画。
*
* *****************************************************************
*/
ValueAnimator colorAnim = ObjectAnimator.ofInt(this,
"backgroundColor", RED, BLUE);
colorAnim.setDuration(3000);
colorAnim.setEvaluator(new ArgbEvaluator());
colorAnim.setRepeatCount(ValueAnimator.INFINITE);
colorAnim.setRepeatMode(ValueAnimator.REVERSE);
colorAnim.start();
}
@SuppressLint("NewApi")
@Override
public boolean onTouchEvent(MotionEvent event) {
if (event.getAction() != MotionEvent.ACTION_DOWN
&& event.getAction() != MotionEvent.ACTION_MOVE) {
return false;
}
ShapeHolder newBall = addBall(event.getX(), event.getY());
/** Bouncing animation with squash and stretch **/
float startY = newBall.getY();
float endY = getHeight() - 50f;
float h = (float) getHeight();
float eventY = event.getY();
int duration = (int) (500 * ((h - eventY) / h));
ValueAnimator bounceAnim = ObjectAnimator.ofFloat(newBall, "y",
startY, endY);
bounceAnim.setDuration(duration);
bounceAnim.setInterpolator(new AccelerateInterpolator());
ValueAnimator squashAnim1 = ObjectAnimator.ofFloat(newBall, "x",
newBall.getX(), newBall.getX() - 25f);
squashAnim1.setDuration(duration / 4);
squashAnim1.setRepeatCount(1);
squashAnim1.setRepeatMode(ValueAnimator.REVERSE);
squashAnim1.setInterpolator(new DecelerateInterpolator());
ValueAnimator squashAnim2 = ObjectAnimator.ofFloat(newBall,
"width", newBall.getWidth(), newBall.getWidth() + 50);
squashAnim2.setDuration(duration / 4);
squashAnim2.setRepeatCount(1);
squashAnim2.setRepeatMode(ValueAnimator.REVERSE);
squashAnim2.setInterpolator(new DecelerateInterpolator());
ValueAnimator stretchAnim1 = ObjectAnimator.ofFloat(newBall, "y",
endY, endY + 25f);
stretchAnim1.setDuration(duration / 4);
stretchAnim1.setRepeatCount(1);
stretchAnim1.setInterpolator(new DecelerateInterpolator());
stretchAnim1.setRepeatMode(ValueAnimator.REVERSE);
ValueAnimator stretchAnim2 = ObjectAnimator.ofFloat(newBall,
"height", newBall.getHeight(), newBall.getHeight() - 25);
stretchAnim2.setDuration(duration / 4);
stretchAnim2.setRepeatCount(1);
stretchAnim2.setInterpolator(new DecelerateInterpolator());
stretchAnim2.setRepeatMode(ValueAnimator.REVERSE);
ValueAnimator bounceBackAnim = ObjectAnimator.ofFloat(newBall, "y",
endY, startY);
bounceBackAnim.setDuration(duration);
bounceBackAnim.setInterpolator(new DecelerateInterpolator());
// Sequence the down/squash&stretch/up animations
AnimatorSet bouncer = new AnimatorSet();
bouncer.play(bounceAnim).before(squashAnim1);
bouncer.play(squashAnim1).with(squashAnim2);
bouncer.play(squashAnim1).with(stretchAnim1);
bouncer.play(squashAnim1).with(stretchAnim2);
bouncer.play(bounceBackAnim).after(stretchAnim2);
// Fading animation - remove the ball when the animation is done
ValueAnimator fadeAnim = ObjectAnimator.ofFloat(newBall, "alpha",
1f, 0f);
fadeAnim.setDuration(250);
fadeAnim.addListener(new AnimatorListenerAdapter() {
@Override
public void onAnimationEnd(Animator animation) {
balls.remove(((ObjectAnimator) animation).getTarget());
}
});
// Sequence the two animations to play one after the other
AnimatorSet animatorSet = new AnimatorSet();
animatorSet.play(bouncer).before(fadeAnim);
// Start the animation
animatorSet.start();
return true;
}
private ShapeHolder addBall(float x, float y) {
OvalShape circle = new OvalShape();
circle.resize(50f, 50f);
ShapeDrawable drawable = new ShapeDrawable(circle);
ShapeHolder shapeHolder = new ShapeHolder(drawable);
shapeHolder.setX(x - 25f);
shapeHolder.setY(y - 25f);
int red = (int) (Math.random() * 255);
int green = (int) (Math.random() * 255);
int blue = (int) (Math.random() * 255);
int color = 0xff000000 | red << 16 | green << 8 | blue;
Paint paint = drawable.getPaint(); // new
// Paint(Paint.ANTI_ALIAS_FLAG);
int darkColor = 0xff000000 | red / 4 << 16 | green / 4 << 8 | blue
/ 4;
RadialGradient gradient = new RadialGradient(37.5f, 12.5f, 50f,
color, darkColor, Shader.TileMode.CLAMP);
paint.setShader(gradient);
shapeHolder.setPaint(paint);
balls.add(shapeHolder);
return shapeHolder;
}
@Override
protected void onDraw(Canvas canvas) {
for (int i = 0; i < balls.size(); ++i) {
ShapeHolder shapeHolder = balls.get(i);
canvas.save();
canvas.translate(shapeHolder.getX(), shapeHolder.getY());
shapeHolder.getShape().draw(canvas);
canvas.restore();
}
}
}
}
自定义
ShapeHolder
如下：
/*
* Copyright (C) 2010 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.edaixi.tempbak;
import android.graphics.Paint;
import android.graphics.RadialGradient;
import android.graphics.drawable.ShapeDrawable;
import android.graphics.drawable.shapes.Shape;
/**
* A data structure that holds a Shape and various properties that can be used to define
* how the shape is drawn.
*/
public class ShapeHolder {
private float x = 0, y = 0;
private ShapeDrawable shape;
private int color;
private RadialGradient gradient;
private float alpha = 1f;
private Paint paint;
public void setPaint(Paint value) {
paint = value;
}
public Paint getPaint() {
return paint;
}
public void setX(float value) {
x = value;
}
public float getX() {
return x;
}
public void setY(float value) {
y = value;
}
public float getY() {
return y;
}
public void setShape(ShapeDrawable value) {
shape = value;
}
public ShapeDrawable getShape() {
return shape;
}
public int getColor() {
return color;
}
public void setColor(int value) {
shape.getPaint().setColor(value);
color = value;
}
public void setGradient(RadialGradient value) {
gradient = value;
}
public RadialGradient getGradient() {
return gradient;
}
public void setAlpha(float alpha) {
this.alpha = alpha;
shape.setAlpha((int)((alpha * 255f) + .5f));
}
public float getWidth() {
return shape.getShape().getWidth();
}
public void setWidth(float width) {
Shape s = shape.getShape();
s.resize(width, s.getHeight());
}
public float getHeight() {
return shape.getShape().getHeight();
}
public void setHeight(float height) {
Shape s = shape.getShape();
s.resize(s.getWidth(), height);
}
public ShapeHolder(ShapeDrawable s) {
shape = s;
}
}
自定义Layout布局渐变背景如下：
package com.edaixi.tempbak;
import android.animation.ArgbEvaluator;
import android.animation.ObjectAnimator;
import android.animation.ValueAnimator;
import android.annotation.SuppressLint;
import android.content.Context;
import android.util.AttributeSet;
import android.widget.RelativeLayout;
@SuppressLint("NewApi")
public class CustomerRelativeLayout extends RelativeLayout {
private static final int RED = 0xffFF8080;
private static final int BLUE = 0xff8080FF;
public CustomerRelativeLayout(Context context) {
super(context);
setBg();
}
public CustomerRelativeLayout(Context context, AttributeSet attrs,
int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
setBg();
}
public CustomerRelativeLayout(Context context, AttributeSet attrs,
int defStyleAttr) {
super(context, attrs, defStyleAttr);
setBg();
}
public CustomerRelativeLayout(Context context, AttributeSet attrs) {
super(context, attrs);
setBg();
}
public void setBg() {
ValueAnimator colorAnim = ObjectAnimator.ofInt(this, "backgroundColor",
RED, BLUE);
colorAnim.setDuration(3000);
colorAnim.setEvaluator(new ArgbEvaluator());
colorAnim.setRepeatCount(ValueAnimator.INFINITE);
colorAnim.setRepeatMode(ValueAnimator.REVERSE);
colorAnim.start();
}
}
布局中引用即可“
<?xml version="1.0" encoding="utf-8"?>
<com.edaixi.tempbak.CustomerRelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/rl_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
</com.edaixi.tempbak.CustomerRelativeLayout>