How did the ball movement

interface

I want to draw a small ball movement on the screen, the results did not respond

 
package com.example.systemaction; 

import android.R.integer; 
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.os.Looper; 
import android.os.Message; 
import android.util.AttributeSet; 
import android.view.View; 

public class BallActivity extends Activity {

@ Override 
public void onCreate (Bundle savedInstanceState) {
super.onCreate (savedInstanceState); 
MyView v = new MyView (this, null); 
setContentView (v); 
} 

class MyView extends View implements Runnable {

private int cx = 20, cy = 20; 

public MyView (Context context, AttributeSet attrs) {
super (context, attrs); 
setFocusable (true); 
. new Thread (this) start (); 
} 

@ Override 
public void run () {
Looper.prepare (); 
ReFreshHandle handler = new ReFreshHandle (); 
while (! Thread.currentThread (). isInterrupted ()) {
/ / Send the message to update the interface 
Message message = new Message (); 
message.what = 0x101; 
handler.sendMessage (message); 
try {
Thread.sleep (100); 
} Catch (InterruptedException i) 
{
i.printStackTrace (); 
} 
} 
Looper.loop (); 
} 

/ / Draw a small ball 
@ Override 
protected void onDraw (Canvas canvas) {
super.onDraw (canvas); 
Paint paint = new Paint (); 
paint.setColor (Color.GREEN); 
canvas.drawCircle (cx, cy, 10, paint); 
} 

/ / Update interface processor 
class ReFreshHandle extends Handler {

@ Override 
public void handleMessage (Message msg) {
if (msg.what == 0x101) {
MyView.this.update (); 
MyView.this.invalidate (); 
} 
super.handleMessage (msg); 
} 
} 

/ / Update the coordinates of ball movement 
public void update () {
int h = getHeight (); 
cy + = 5; 
if (cy> = h) {
cy = 20; 
} 

} 
} 
} 

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Reply:
You print your thread under the look did not start.
Reply:
The ReFreshHandle handler = new ReFreshHandle ();
Put out, do not put run in

Reply:

reference to the second floor hjywyj reply:

will ReFreshHandle handler = new ReFreshHandle ();
Put out, do not run into the inside

ah, I really was not careful, thank you