自定义360摇杆-封装类

import android.graphics.Canvas;
import android.view.MotionEvent;

public class Joystick {

private float smallCenterX, smallCenterY, smallCenterR;
private float bigCenterX, bigCenterY, bigCenterR;


//构造函数
public Joystick(){
bigCenterR = (位图-大圆).getWidth()/2;
bigCenterX = 80+bigCenterR;
bigCenterY = （屏幕高度）-60-bigCenterR;

smallCenterR = (位图-小圆).getWidth()/2;
smallCenterX = 80+bigCenterR; 
smallCenterY = （屏幕高度）-60-bigCenterR;
}

//画图函数
public void draw(Canvas canvas) {
canvas.drawBitmap((位图-大圆), bigCenterX-bigCenterR, bigCenterY-bigCenterR, null);
canvas.drawBitmap((位图-小圆), smallCenterX-smallCenterR, smallCenterY-smallCenterR, null);
}

//得到弧度
public double getRad(float px1, float py1, float px2, float py2){

float x = px2 - px1;