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package com.example.ballviewdemo;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.WindowManager;
/**
* Created by Administrator on 2017/11/2 0002.
*/
//自定义类继承视图
public class BallDemo extends View{
private int x = 100;
private int y = 100;
Context context;
public BallDemo(Context context) {
this(context,null);
}public BallDemo(Context context, @Nullable AttributeSet attrs) {
this(context, attrs,0);
}public BallDemo(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
this.context = context;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Paint paint = new Paint();
//设置画笔颜色
paint.setColor(Color.RED);
//画圆
canvas.drawCircle(x,y,20,paint);
}@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction())
{
case MotionEvent.ACTION_DOWN:
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_UP:
x = (int) event.getX();
y = (int) event.getY();
break;
}
WindowManager manager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
int width = manager.getDefaultDisplay().getWidth();
int height = manager.getDefaultDisplay().getHeight();
if(x>=20&&y>=20&&x<=width-20&&y<=height-90)
{
invalidate();
}
return true;
}
}
//在主方法的布局中调用视图
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