Android Handler练习

package com.example.myact12;


import java.util.Random;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
/**
 * Android handler
 * @Describe: 
 * @package: com.example.myact12
 * @author shaobn
 * @date 2015-9-16 上午10:11:50
 */
public class MainActivity extends ActionBarActivity {
    private Button start;
    private Button end;
    private TextView textView;
    private Handler handler = new Handler();
        
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        start = (Button) this.findViewById(R.id.button1);
        end = (Button) this.findViewById(R.id.button2);
        textView = (TextView) this.findViewById(R.id.textView1);
        start.setOnClickListener(new ButtonClick());
        end.setOnClickListener(new ButtonClick());
    }
    class ButtonClick implements View.OnClickListener{
        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
                switch (arg0.getId()) {
                case R.id.button1:
                    Runnable runnable = new Runnable() {
                        
                        @Override
                        public void run() {
                            // TODO Auto-generated method stub
                            Random random = new Random();
                            final int num = random.nextInt(100);
                            Runnable runnable2 = new Runnable() {
                                
                                @Override
                                public void run() {
                                    // TODO Auto-generated method stub
                                    try {
                                        Thread.sleep(1000);
                                    } catch (Exception e) {
                                        // TODO: handle exception
                                        e.printStackTrace();
                                    }
                                    
                                    MainActivity.this.textView.setText(String.valueOf(num));
                                }
                            };
                            
                            MainActivity.this.handler.post(runnable2);
                        }
                    };
                    new Thread(runnable).start();
                    break;

                case R.id.button2:
                    Runnable runnable2 = new Runnable() {
                        
                        @Override
                        public void run() {
                            // TODO Auto-generated method stub
                            
                        }
                    };
                    break;
                }
                
            
        }
        
        
    }
}