本文介绍了Android实现红包雨动画效果，分享给大家，希望对大家有帮助
红包雨
关于实现上面红包雨效果步骤如下：
1.创建一个红包实体类
代码语言：javascript复制public class RedPacket {
public float x, y;
public float rotation;
public float speed;
public float rotationSpeed;
public int width, height;
public Bitmap bitmap;
public int money;
public boolean isRealRed;
public RedPacket(Context context, Bitmap originalBitmap, int speed, float maxSize, float minSize, int viewWidth) {
//获取一个显示红包大小的倍数
double widthRandom = Math.random();
if (widthRandom < minSize || widthRandom maxSize) {
widthRandom = maxSize;
}
//红包的宽度
width = (int) (originalBitmap.getWidth() * widthRandom);
//红包的高度
height = width * originalBitmap.getHeight() / originalBitmap.getWidth();
int mWidth = (viewWidth == 0) ? context.getResources().getDisplayMetrics().widthPixels : viewWidth;
//生成红包bitmap
bitmap = Bitmap.createScaledBitmap(originalBitmap, width, height, true);
originalBitmap.recycle();
Random random = new Random();
//红包起始位置x:[0,mWidth-width]
int rx = random.nextInt(mWidth) - width;
x = rx <= 0 ? 0 : rx;
//红包起始位置y
y = -height;
//初始化该红包的下落速度
this.speed = speed (float) Math.random() * 1000;
//初始化该红包的初始旋转角度
rotation = (float) Math.random() * 180 - 90;
//初始化该红包的旋转速度
rotationSpeed = (float) Math.random() * 90 - 45;
//初始化是否为中奖红包
isRealRed = isRealRedPacket();
}
/**
* 判断当前点是否包含在区域内
*/
public boolean isContains(float x, float y) {
//稍微扩大下点击的区域
return this.x-50 < x && this.x 50 width x
&& this.y-50 < y && this.y 50 height y;
}
/**
* 随机 是否为中奖红包
*/
public boolean isRealRedPacket() {
Random random = new Random();
int num = random.nextInt(10) 1;
//如果[1,10]随机出的数字是2的倍数 为中奖红包
if (num % 2 == 0) {
money = num*2;//中奖金额
return true;
}
return false;
}
/**
* 回收图片
*/
public void recycle() {
if (bitmap!= null && !bitmap.isRecycled()){
bitmap.recycle();
}
}
}上面就红包实体类的源码，重点就是在创建红包实体的时候，初始化红包相关的值，如生成红包图片，图片的宽高，红包初始位置，下落速度等。比较简单。
2.自定义红包雨view
view初始化
代码语言：javascript复制 public RedPacketTest(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
final TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.RedPacketStyle);
//获取xml中配置的view的style属性，如下落红包数量，下落的基础速度，以及红包图片的最大最小范围
count = typedArray.getInt(R.styleable.RedPacketStyle_count, 20);
speed = typedArray.getInt(R.styleable.RedPacketStyle_speed, 20);
minSize = typedArray.getFloat(R.styleable.RedPacketStyle_min_size, 0.5f);
maxSize = typedArray.getFloat(R.styleable.RedPacketStyle_max_size, 1.2f);
typedArray.recycle();
init();
}
/**
* 初始化
*/
private void init() {
//初始化画笔
paint = new Paint();
paint.setFilterBitmap(true);
paint.setDither(true);
paint.setAntiAlias(true);
//创建一个属性动画，通过属性动画来控制刷新红包下落的位置
animator = ValueAnimator.ofFloat(0, 1);
//绘制view开启硬件加速
setLayerType(View.LAYER_TYPE_HARDWARE, null);
//初始化属性动画
initAnimator();
}
private void initAnimator() {
//每次动画更新的时候，更新红包下落的坐标值
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
long nowTime = System.currentTimeMillis();
//获取两次动画更新之间的时间，以此来计算下落的高度
float secs = (float) (nowTime - prevTime) / 1000f;
prevTime = nowTime;
for (int i = 0; i < redpacketlist.size(); i) {
RedPacket redPacket = redpacketlist.get(i);
//更新红包的下落的位置y
redPacket.y = (redPacket.speed * secs);
//如果y坐标大于view的高度 说明划出屏幕，y重新设置起始位置，以及中奖属性
if (redPacket.y getHeight()) {
redPacket.y = 0 - redPacket.height;
redPacket.isRealRed = redPacket.isRealRedPacket();
}
//更新红包的旋转的角度
redPacket.rotation = redPacket.rotation
(redPacket.rotationSpeed * secs);
}
//重绘
invalidate();
}
});
//属性动画无限循环
animator.setRepeatCount(ValueAnimator.INFINITE);
//属性值线性变换
animator.setInterpolator(new LinearInterpolator());
animator.setDuration(0);
}view绘制
代码语言：javascript复制 @Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
//获取自定义view的宽度
mWidth = getMeasuredWidth();
}
@Override
protected void onDraw(final Canvas canvas) {
//遍历红包数组，绘制红包
for (int i = 0; i < redpacketlist.size(); i ) {
RedPacket redPacket = redpacketlist.get(i);
//将红包旋转redPacket.rotation角度后 移动到（redPacket.x，redPacket.y）进行绘制红包
Matrix m = new Matrix();
m.setTranslate(-redPacket.width / 2, -redPacket.height / 2);
m.postRotate(redPacket.rotation);
m.postTranslate(redPacket.width / 2 redPacket.x, redPacket.height / 2 redPacket.y);
//绘制红包
canvas.drawBitmap(redPacket.bitmap, m, paint);
}
}红包雨动画开始结束
代码语言：javascript复制 /**
*停止动画
*/
public void stopRainNow() {
//清空红包数据
clear();
//重绘
invalidate();
//动画取消
animator.cancel();
}
/**
* 开始动画
*/
public void startRain() {
//清空红包数据
clear();
//添加红包
setRedpacketCount(count);
prevTime = System.currentTimeMillis();
//动画开始
animator.start();
}
public void setRedpacketCount(int count) {
if (mImgIds == null || mImgIds.length == 0)
return;
for (int i = 0; i < count; i) {
//获取红包原始图片
Bitmap originalBitmap = BitmapFactory.decodeResource(getResources(), mImgIds[0]);
//生成红包实体类
RedPacket redPacket = new RedPacket(getContext(), originalBitmap, speed,maxSize,minSize,mWidth);
//添加进入红包数组
redpacketlist.add(redPacket);
}
}
/**
* 暂停红包雨
*/
public void pauseRain() {
animator.cancel();
}
/**
* 重新开始
*/
public void restartRain() {
animator.start();
}
/**
* 清空红包数据，并回收红包中的bitmap
*/
private void clear() {
for (RedPacket redPacket :redpacketlist) {
redPacket.recycle();
}
redpacketlist.clear();
}红包点击事件
代码语言：javascript复制 @Override
public boolean onTouchEvent(MotionEvent motionEvent) {
switch (motionEvent.getAction()){
case MotionEvent.ACTION_DOWN:
//根据点击的坐标点，判断是否点击在红包的区域
RedPacket redPacket = isRedPacketClick(motionEvent.getX(), motionEvent.getY());
if (redPacket != null) {
//如果点击在红包上，重新设置起始位置，以及中奖属性
redPacket.y = 0 - redPacket.height;
redPacket.isRealRed = redPacket.isRealRedPacket();
if (onRedPacketClickListener != null) {
onRedPacketClickListener.onRedPacketClickListener(redPacket);
}
}
break;
case MotionEvent.ACTION_MOVE:
break;
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP:
break;
}
return true;
}
//根据点击坐标点，遍历红包数组，看是否点击在红包上
private RedPacket isRedPacketClick(float x, float y) {
for (int i = redpacketlist.size() - 1; i = 0; i --) {
if (redpacketlist.get(i).isContains(x, y)) {
return redpacketlist.get(i);
}
}
return null;
}关于自定义红包雨view的主要代码以及分析基本完成了。下面是自定义view的使用。
3.自定义view的使用
红包雨Activity
代码语言：javascript复制public class RedPacketActivity extends AppCompatActivity implements View.OnClickListener {
private RedPacketTest redRainView1;
private Button start, stop;
private TextView money;
private int totalmoney = 0;
AlertDialog.Builder ab;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.red_rain);
ab = new AlertDialog.Builder(RedPacketActivity.this);
start = (Button) findViewById(R.id.start);
stop = (Button) findViewById(R.id.stop);
money = (TextView) findViewById(R.id.money);
redRainView1 = (RedPacketTest) findViewById(R.id.red_packets_view1);
start.setOnClickListener(this);
stop.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.start) {
startRedRain();
} else if (v.getId() == R.id.stop) {
stopRedRain();
}
}
/**
* 开始下红包雨
*/
private void startRedRain() {
redRainView1.startRain();
redRainView1.setOnRedPacketClickListener(new RedPacketTest.OnRedPacketClickListener() {
@Override
public void onRedPacketClickListener(RedPacket redPacket) {
redRainView1.pauseRain();
ab.setCancelable(false);
ab.setTitle("红包提醒");
ab.setNegativeButton("继续抢红包", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
redRainView1.restartRain();
}
});
if (redPacket.isRealRed) {
ab.setMessage("恭喜你，抢到了" redPacket.money "元！");
totalmoney = redPacket.money;
money.setText("中奖金额: " totalmoney);
} else {
ab.setMessage("很遗憾，下次继续努力！");
}
redRainView1.post(new Runnable() {
@Override
public void run() {
ab.show();
}
});
}
});
}
/**
* 停止下红包雨
*/
private void stopRedRain() {
totalmoney = 0;//金额清零
redRainView1.stopRainNow();
}红包雨Activity的xml
代码语言：javascript复制<?xml version="1.0" encoding="utf-8"?
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#80000000"
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="fitXY"
android:src="@drawable/red_packets_bg" /
<Button
android:id="@ id/start"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="开始"
/
<Button
android:id="@ id/stop"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:text="结束"
/
<TextView
android:id="@ id/money"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:text="中奖金额:"
android:textSize="18sp"
android:layout_marginTop="10dp"
/
<com.example.test.redpacketrain.RedPacketTest
android:id="@ id/red_packets_view1"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:count="20"
app:max_size="0.8"
app:min_size="0.6"
app:speed="500" /
</RelativeLayout 自定义view的styleable
代码语言：javascript复制<resources
<declare-styleable name="RedPacketStyle"
<attr name="count" format="integer" /
<attr name="speed" format="integer" /
<attr name="max_size" format="float" /
<attr name="min_size" format="float" /
</declare-styleable
</resources 完整的自定义view代码
代码语言：javascript复制public class RedPacketTest extends View {
private int[] mImgIds = new int[]{
R.drawable.red_packets_icon
};//红包图片
private int count;//红包数量
private int speed;//下落速度
private float maxSize;//红包大小的范围
private float minSize;//红包大小的范围
private int mWidth;//view宽度
private ValueAnimator animator;//属性动画，用该动画来不断改变红包下落的坐标值
private Paint paint;//画笔
private long prevTime;
private ArrayList<RedPacket redpacketlist = new ArrayList< ();//红包数组
public RedPacketTest(Context context) {
super(context);
init();
}
public RedPacketTest(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
final TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.RedPacketStyle);
count = typedArray.getInt(R.styleable.RedPacketStyle_count, 20);
speed = typedArray.getInt(R.styleable.RedPacketStyle_speed, 20);
minSize = typedArray.getFloat(R.styleable.RedPacketStyle_min_size, 0.5f);
maxSize = typedArray.getFloat(R.styleable.RedPacketStyle_max_size, 1.2f);
typedArray.recycle();
init();
}
/**
* 初始化
*/
private void init() {
paint = new Paint();
paint.setFilterBitmap(true);
paint.setDither(true);
paint.setAntiAlias(true);
animator = ValueAnimator.ofFloat(0, 1);
setLayerType(View.LAYER_TYPE_HARDWARE, null);
initAnimator();
}
private void initAnimator() {
//每次动画更新的时候，更新红包下落的坐标值
animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) {
long nowTime = System.currentTimeMillis();
float secs = (float) (nowTime - prevTime) / 1000f;
prevTime = nowTime;
for (int i = 0; i < redpacketlist.size(); i) {
RedPacket redPacket = redpacketlist.get(i);
//更新红包的下落的位置y
redPacket.y = (redPacket.speed * secs);
//如果y坐标大于view的高度 说明划出屏幕，y重新设置起始位置，以及中奖属性
if (redPacket.y getHeight()) {
redPacket.y = 0 - redPacket.height;
redPacket.isRealRed = redPacket.isRealRedPacket();
}
//更新红包的旋转的角度
redPacket.rotation = redPacket.rotation
(redPacket.rotationSpeed * secs);
}
invalidate();
}
});
//属性动画无限循环
animator.setRepeatCount(ValueAnimator.INFINITE);
//属性值线性变换
animator.setInterpolator(new LinearInterpolator());
animator.setDuration(0);
}
/**
*停止动画
*/
public void stopRainNow() {
//清空红包数据
clear();
//重绘
invalidate();
//动画取消
animator.cancel();
}
/**
* 开始动画
*/
public void startRain() {
//清空红包数据
clear();
//添加红包
setRedpacketCount(count);
prevTime = System.currentTimeMillis();
//动画开始
animator.start();
}
public void setRedpacketCount(int count) {
if (mImgIds == null || mImgIds.length == 0)
return;
for (int i = 0; i < count; i) {
//获取红包原始图片
Bitmap originalBitmap = BitmapFactory.decodeResource(getResources(), mImgIds[0]);
//生成红包实体类
RedPacket redPacket = new RedPacket(getContext(), originalBitmap, speed,maxSize,minSize,mWidth);
//添加进入红包数组
redpacketlist.add(redPacket);
}
}
/**
* 暂停红包雨
*/
public void pauseRain() {
animator.cancel();
}
/**
* 重新开始
*/
public void restartRain() {
animator.start();
}
/**
* 清空红包数据，并回收红包中的bitmap
*/
private void clear() {
for (RedPacket redPacket :redpacketlist) {
redPacket.recycle();
}
redpacketlist.clear();
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
//获取自定义view的宽度
mWidth = getMeasuredWidth();
}
@Override
protected void onDraw(final Canvas canvas) {
//遍历红包数组，绘制红包
for (int i = 0; i < redpacketlist.size(); i ) {
RedPacket redPacket = redpacketlist.get(i);
//将红包旋转redPacket.rotation角度后 移动到（redPacket.x，redPacket.y）进行绘制红包
Matrix m = new Matrix();
m.setTranslate(-redPacket.width / 2, -redPacket.height / 2);
m.postRotate(redPacket.rotation);
m.postTranslate(redPacket.width / 2 redPacket.x, redPacket.height / 2 redPacket.y);
//绘制红包
canvas.drawBitmap(redPacket.bitmap, m, paint);
}
}
@Override
public boolean onTouchEvent(MotionEvent motionEvent) {
switch (motionEvent.getAction()){
case MotionEvent.ACTION_DOWN:
//根据点击的坐标点，判断是否点击在红包的区域
RedPacket redPacket = isRedPacketClick(motionEvent.getX(), motionEvent.getY());
if (redPacket != null) {
//如果点击在红包上，重新设置起始位置，以及中奖属性
redPacket.y = 0 - redPacket.height;
redPacket.isRealRed = redPacket.isRealRedPacket();
if (onRedPacketClickListener != null) {
onRedPacketClickListener.onRedPacketClickListener(redPacket);
}
}
break;
case MotionEvent.ACTION_MOVE:
break;
case MotionEvent.ACTION_CANCEL:
case MotionEvent.ACTION_UP:
break;
}
return true;
}
//根据点击坐标点，遍历红包数组，看是否点击在红包上
private RedPacket isRedPacketClick(float x, float y) {
for (int i = redpacketlist.size() - 1; i = 0; i --) {
if (redpacketlist.get(i).isContains(x, y)) {
return redpacketlist.get(i);
}
}
return null;
}
public interface OnRedPacketClickListener {
void onRedPacketClickListener(RedPacket redPacket);
}
private OnRedPacketClickListener onRedPacketClickListener;
public void setOnRedPacketClickListener(OnRedPacketClickListener onRedPacketClickListener) {
this.onRedPacketClickListener = onRedPacketClickListener;
}
}最后
以上就是本文的全部内容，希望对大家的学习有所帮助。
