Android中常用的系统服务

后台Service在系统启动时被SystemService开启

MountService：监听是否有SD卡安装及移除

ClipboardService：提供剪切板功能

PackageManagerService：提供软件包的安装移除及查看

电量、网络连接状态等

getSystemService()

Activity的一个方法

传入NAME -> Object -> 服务对象

常用系统服务

判断网络是否连接

开关WIFI

获取当前的系统音量

获取当前运行的程序包名

布局填充器

通知管理器

    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

获取网络状态

    public void doClick(View v) {
    	switch (v.getId()) {
		case R.id.network:
			if (isNetWorkConnected(MainActivity.this) == true) {
				Toast.makeText(MainActivity.this, "网络已经打开", Toast.LENGTH_SHORT).show();
			} else {
				Toast.makeText(MainActivity.this, "网络未连接", Toast.LENGTH_SHORT).show();
			}
			break;

		default:
			break;
		}
    }
    
    public boolean isNetWorkConnected(Context context) {
    	if (context != null) {
    		ConnectivityManager mConnectivityManager = (ConnectivityManager) context.getSystemService(CONNECTIVITY_SERVICE);
    		NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
    		if (mNetworkInfo != null) {
    			return mNetworkInfo.isAvailable();
    		}
    	}
    	return false;
    }

    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>

    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>

打开或关闭WIFI

		case R.id.enableOrDisable_WIFI:
			WifiManager wifiManager = (WifiManager) MainActivity.this.getSystemService(WIFI_SERVICE);
			if (wifiManager.isWifiEnabled()) {
				wifiManager.setWifiEnabled(false);
				Toast.makeText(MainActivity.this, "WIFI已经关闭", Toast.LENGTH_SHORT).show();
			} else {
				wifiManager.setWifiEnabled(true);
				Toast.makeText(MainActivity.this, "WIFI已经打开", Toast.LENGTH_SHORT).show();
			}
			break;

获取音量

		case R.id.getvoice:
			AudioManager mAudioManager = (AudioManager) MainActivity.this.getSystemService(AUDIO_SERVICE);
			int max = mAudioManager.getStreamMaxVolume(AudioManager.STREAM_SYSTEM);
			int current = mAudioManager.getStreamVolume(AudioManager.STREAM_RING);
			Toast.makeText(MainActivity.this, "max : " + max + " current : " + current, Toast.LENGTH_SHORT).show();
			break;

获取包名

    <uses-permission android:name="android.permission.GET_TASKS"/>

		case R.id.getPackageName:
			ActivityManager activityManager = (ActivityManager) MainActivity.this.getSystemService(ACTIVITY_SERVICE);
			String packageName = activityManager.getRunningTasks(1).get(0).topActivity.getPackageName();
			Toast.makeText(MainActivity.this, "当前运行的Activity包名 ： " + packageName, Toast.LENGTH_SHORT).show();
			break;