Android抽奖轮盘的制作方法

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:layout_gravity="center" 

  <ImageView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:src="@drawable/bigwheelgg"
    / 

  <ImageView
    android:id="@+id/light"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:src="@drawable/light"
    / 

  <ImageView
    android:id="@+id/main_wheel"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:src="@drawable/bigwheel"
    / 

  <ImageView
    android:id="@+id/point"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:src="@drawable/point"
    / 


</FrameLayout 

//设置一个时间常量，此常量有两个作用，1.圆灯视图显示与隐藏中间的切换时间；2.指针转一圈所需要的时间，现设置为500毫秒
private static final long ONE_WHEEL_TIME = 500;
//记录圆灯视图是否显示的布尔常量
private boolean lightsOn = true;
//开始转动时候的角度，初始值为0
private int startDegree = 0;
private ImageView lightIv;
private ImageView pointIv;
private ImageView wheelIv;
//指针转圈圈数数据源
private int[] laps = { 5, 7, 10, 15 };
//指针所指向的角度数据源，因为有6个选项，所有此处是6个值
private int[] angles = { 0, 60, 120, 180, 240, 300 };
//转盘内容数组
private String[] lotteryStr = { "索尼PSP", "10元红包", "谢谢参与", "DNF钱包",
"OPPO MP3", "5元红包", };
//子线程与UI线程通信的handler对象
private Handler mHandler = new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case 0:
if (lightsOn) {
// 设置lightIv不可见
lightIv.setVisibility(View.INVISIBLE);
lightsOn = false;
} else {
// 设置lightIv可见
lightIv.setVisibility(View.VISIBLE);
lightsOn = true;
}
break;
default:
break;
}
};
};
//监听动画状态的监听器
private Animation.AnimationListener al = new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
// TODO Auto-generated method stub
}
@Override
public void onAnimationRepeat(Animation animation) {
// TODO Auto-generated method stub
}
@Override
public void onAnimationEnd(Animation animation) {
String name = lotteryStr[startDegree % 360 / 60];
Toast.makeText(MainActivity.this, name, Toast.LENGTH_LONG).show();
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
setupViews();
flashLights();
pointIv.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int lap = laps[(int) (Math.random() * 4)];
int angle = angles[(int) (Math.random() * 6)];
//每次转圈角度增量
int increaseDegree = lap * 360 + angle;
//初始化旋转动画，后面的四个参数是用来设置以自己的中心点为圆心转圈
RotateAnimation rotateAnimation = new RotateAnimation(
startDegree, startDegree + increaseDegree,
RotateAnimation.RELATIVE_TO_SELF, 0.5f,
RotateAnimation.RELATIVE_TO_SELF, 0.5f);
//将最后的角度赋值给startDegree作为下次转圈的初始角度
startDegree += increaseDegree;
//计算动画播放总时间
long time = (lap + angle / 360) * ONE_WHEEL_TIME;
//设置动画播放时间
rotateAnimation.setDuration(time);
//设置动画播放完后，停留在最后一帧画面上
rotateAnimation.setFillAfter(true);
//设置动画的加速行为，是先加速后减速
rotateAnimation.setInterpolator(MainActivity.this,
android.R.anim.accelerate_decelerate_interpolator);
//设置动画的监听器
rotateAnimation.setAnimationListener(al);
//开始播放动画
pointIv.startAnimation(rotateAnimation);
}
});
}
private void setupViews(){
lightIv = (ImageView) findViewById(R.id.light);
pointIv = (ImageView) findViewById(R.id.point);
wheelIv = (ImageView) findViewById(R.id.main_wheel);
}
//控制灯圈动画的方法
private void flashLights() {
Timer timer = new Timer();
TimerTask tt = new TimerTask() {
@Override
public void run() {
// 向UI线程发送消息
mHandler.sendEmptyMessage(0);
}
};
// 每隔ONE_WHEEL_TIME毫秒运行tt对象的run方法
timer.schedule(tt, 0, ONE_WHEEL_TIME);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}