Android活动组件的基本用法

销毁一个活动

package com.example.activitytest;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.widget.Button;
import android.widget.Toast;

public class FirstActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		requestWindowFeature(Window.FEATURE_NO_TITLE);//隐藏标题栏
		setContentView(R.layout.first_layout);//加载布局
		
		Button button1 = (Button)findViewById(R.id.button_1);
		button1.setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				//Toast.makeText(FirstActivity.this, "You clicked Button 1", Toast.LENGTH_SHORT).show();
				finish();//销毁一个活动, finish和按下back键效果一样
			}
		});
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menua) {
		// TODO Auto-generated method stub
		getMenuInflater().inflate(R.menu.main, menua);//菜单默认是不会显示出来的，只用按下了menu键，菜单才会在底部显示出来。
		return true;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		// TODO Auto-generated method stub
		switch (item.getItemId()) {
		case R.id.add_item:
			Toast.makeText(this, "You clicked Add", Toast.LENGTH_LONG).show();			
			break;
			
		case R.id.remove_item:
			Toast.makeText(this, "You clicked remove_item", Toast.LENGTH_SHORT).show();			
			break;
		default:
			break;
		}
		return super.onOptionsItemSelected(item);
	}
	
	
	
}

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.activitytest"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="18" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        
        <activity 
            android:name="com.example.activitytest.FirstActivity"
            android:label="This is FirstActivity01">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
            
        </activity>
        
    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android" >
    <item 
        android:id="@+id/add_item"
        android:title="Add"/>
    <item 
        android:id="@+id/remove_item"
        android:title="Remove"/>

</menu>