1 package com.example.learntest;
 2 
 3 import android.app.Activity;
 4 import android.os.Bundle;
 5 import android.view.View;
 6 import android.view.View.OnClickListener;
 7 import android.widget.Button;
 8 import android.widget.Toast;
 9 
10 public class MainActivity extends Activity {
11 
12  long time = (long)0.0;
13  public void onCreate(Bundle savedInstanceState) {
14   super.onCreate(savedInstanceState);  
15   setContentView(R.layout.activity_main);
16 
17   Button btn_mainActivity  =  (Button)findViewById(R.id.btn_mainAc_1);
18   btn_mainActivity.setOnClickListener(new ButtonListen());
19  }
20 
21  
22  class ButtonListen implements OnClickListener{
23   public void onClick(View v) {
24    time = System.currentTimeMillis();
25    switch(v.getId()){
26        case R.id.btn_mainAc_1:
27            Jump2Second();
28            break;
29        case R.id.btn_secondA_1:
30            Jump2Main();
31            break;
32        default:
33            break;
34    }
35   }
36  }  //按钮监听部分，非常便于阅读和管理
37 
38  public void Jump2Second(){
39   setContentView(R.layout.activity_second);
40   long currTime = System.currentTimeMillis();
41 
42   Toast.makeText(MainActivity.this,
43     "切换耗时：" +String.valueOf(currTime-time)+"毫秒",
44 
45     Toast.LENGTH_SHORT).show();
46 
47   Button btn_secondActivity = (Button)findViewById(R.id.btn_secondA_1);
48   btn_secondActivity.setOnClickListener(new ButtonListen());
49  }    //跳转到第二个页面方法实现
50 
51  public void Jump2Main(){
52   setContentView(R.layout.activity_main);
53   long currTime = System.currentTimeMillis();
54 
55    Toast.makeText(MainActivity.this,
56     "切换耗时：" +String.valueOf(currTime-time)+"毫秒",
57 
58     Toast.LENGTH_SHORT).show();
59   Button btn_mainActivity = (Button)findViewById(R.id.btn_mainAc_1);
60   btn_mainActivity.setOnClickListener(new ButtonListen());
61  }
62 }   //返回到第一个页面方法实现
63