1     package com.example.test;   2        3     import android.os.Bundle;   4     import android.app.Activity;   5     import android.content.ComponentName;   6     import android.content.Intent;   7     import android.view.Menu;   8     import android.view.View;   9     import android.view.View.OnClickListener;  10     import android.widget.Button;  11       12     public class MainActivity extends Activity {  13       14         @Override  15         protected void onCreate(Bundle savedInstanceState) {  16             super.onCreate(savedInstanceState);  17             setContentView(R.layout.activity_main);  18             Button btn = (Button) findViewById(R.id.btn);  19             btn.setOnClickListener(new OnClickListener() {  20       21                 @Override  22                 public void onClick(View v) {  23                     // TODO Auto-generated method stub  24                     Intent intent = new Intent();  25                     //1.利用setClass  26                     //intent.setClass(MainActivity.this, SencondActivity.class);  27                     //2.利用setComponent ComponentName的第一个参数必须是application‘s package name,也是主配置文件Manifest里设置好的包名  28                     ComponentName name = new ComponentName(getPackageName(), SencondActivity.class.getName());  29                     intent.setComponent(name);  30                     startActivity(intent);  31                 }  32             });  33         }  34       35         @Override  36         public boolean onCreateOptionsMenu(Menu menu) {  37             // Inflate the menu; this adds items to the action bar if it is present.  38             getMenuInflater().inflate(R.menu.activity_main, menu);  39             return true;  40         }  41       42     }  43 44