更新游戏画面时线程的问题

作者daytodayme
http://www.iteye.com/topic/435147

调用Handler.post(Runnable r)方法,Runnable运行在UI所在线程,所以可以直接调用View.invalidate()

引用

package com.ray.test; 
 
import android.app.Activity; 
import android.content.Context; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.os.Bundle; 
import android.os.Handler; 
import android.view.View; 
 
public class TestHandler extends Activity { 
    private MyView myView; 
    private Handler mHandler; 
    public void onCreate(Bundle savedInstanceState) { 
        super.onCreate(savedInstanceState); 
        myView = new MyView(this); 
        mHandler = new Handler(); 
        mHandler.post(new Runnable(){ 
            @Override 
            public void run() { 
                myView.invalidate(); 
                mHandler.postDelayed(this, 5); 
            } 
         }); 
        setContentView(myView); 
    } 
     
    class MyView extends View{ 
        private float x = 0f; 
        public MyView(Context context) { 
            super(context); 
             
    } 
        protected void onDraw(Canvas canvas) { 
            super.onDraw(canvas); 
            x+=1; 
            Paint mPaint = new Paint(); 
            mPaint.setColor(Color.BLUE); 
            canvas.drawRect(x, 40, x+40, 80, mPaint); 
        } 
         
    } 
} 

在新线程里更新UI,可以直接postInvalidate()

public void onCreate(Bundle savedInstanceState) {      
               super.onCreate(savedInstanceState);      
               this.requestWindowFeature(Window.FEATURE_NO_TITLE);      
     
               myView = new MyView(this);  
       this.setContentView(this.myView);      
       new Thread(new myThread()).start();     
}      
    
    class myThread implements Runnable {      
          public void run() {     
              while (!Thread.currentThread().isInterrupted()) {      
                   try {  
                          myView.postInvalidate();   
                        Thread.sleep(100);       
                   } catch (InterruptedException e) {      
                        Thread.currentThread().interrupt();      
                   }      
               }      
          }      
    }