StatusBar的使用_例子讲解

Notification是一般是在Service这种后台服务中发起的，当后台服务要通知用户某一事项时，就发起一个Notification,然后通过这个Notification启动相应的Activity,而Service自己不应该启动Activity.

生成Notification要用到两个类，一个是Notification,两一个是NotificationManager.其实不建议通过Notification的构造函数创建Notification,而是用Notification.Builder来帮助生成。

生成一个Notification的步骤：

1.　得到一个NotificationManger的引用。这个要通过getSystemService(NOTIFICATION_SERVICE)方法来得到.

2.　生成一个Notification对象:

3.　定义Notification的内容和PendingIntent

4.　将Notification传递给NotificationManager

以下为程序例子：在MainActivity中有一个按钮，当点击按钮后会产生一个Notification在status bar中，然后点击打开这个Notification会打开ActionNotification这个Activity.

MainActivity.java:

public class MainActivity extends Activity
{
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

Button button = (Button) findViewById(R.id.btn_notice);
button.setOnClickListener(new OnClickListener()
{

public void onClick(View v)
{
setNotification();
}
});
}

private void setNotification()
{
// 首先得到NotificationManager,通过getSystemService()方法得到
NotificationManager nm = (NotificationManager) getSystemService(NOTIFICATION_SERVICE);
// 生成一个Notification,其实不建议直接采用构造方法，而是用Notification.Builder类生成Notification
Notification notice = new Notification(R.drawable.close2, "have downloaded", System.currentTimeMillis());
// 定义Notification的信息和PendingIntent
Intent intent = new Intent(this, ActionNotification.class);
PendingIntent contentIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
notice.setLatestEventInfo(this, "下载完成", "请打开查看", contentIntent);
// 将Notification传递给NotificationManager
nm.notify(1, notice);
}
}

ActionNotification.java:

public class ActionNotification extends Activity
{
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
TextView textView = new TextView(this);
textView.setText("歌曲 一千年以后　下载完成");
LinearLayout layout = new LinearLayout(this);
layout.addView(textView, new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));

setContentView(layout);
}
}

程序运行结果：







为Notification增加声音提醒:

增加系统默认声音：

notification.defaults |= Notification.DEFAULT_SOUND;

增加自定义声音：

notification.sound = Uri.parse("file:///sdcard/notification/ring.mp3");

为Notification增加震动提醒:

增加系统默认震动：

notification.defaults |= Notification.DEFAULT_VIBRATE;

增加自定义震动：

long[] vibrate = {0. 100. 200, 300};

notification.vibrate = vibrate;

如果需要使用震动功能，需要加入权限：<uses-permission android:name="android.permission.VIBRATE" />

为Notification加入灯闪提醒:

增加系统默认灯闪：

notification.defaults |= Notification.DEFAULT_LIGTHS;

增加自定义灯闪:

notification.ledARGB = 0xff00ff00;
notification.ledOnMS = 300;
notification.ledOffMS = 1000;
notification.flags |= Notification.FLAG_SHOW_LIGHTS;