Android SystemService初体验

由于系统服务比较多就挑了几个试了一下，但是数据开关的还没有找到合适的方法后续再补上

使用到服务的时候别忘记在配置文件中添加相应的权限
MainActivity.class

package com.superxingyun.systemservicedemo;import android.app.ActivityManager;import android.content.Context;import android.media.AudioManager;import android.net.ConnectivityManager;import android.net.NetworkInfo;import android.net.wifi.WifiManager;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.view.LayoutInflater;import android.view.View;import android.widget.Toast;public class MainActivity extends AppCompatActivity {    private ConnectivityManager connManager;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        LayoutInflater inflater = (LayoutInflater) MainActivity.this.getSystemService(LAYOUT_INFLATER_SERVICE);        View view = inflater.inflate(R.layout.activity_main, null);        setContentView(view);    }    public void doClick(View view) {        switch (view.getId()){            case R.id.network:                if (isNetwork(MainActivity.this) == true){//判断网络状态返回值打吐司                    Toast.makeText(MainActivity.this, "网络已连接", Toast.LENGTH_SHORT).show();                } else {                    Toast.makeText(MainActivity.this, "网络未连接", Toast.LENGTH_SHORT).show();                }                break;            case R.id.fouthG:                break;            case R.id.wifi:                WifiManager wifiManager = (WifiManager) MainActivity.this.getSystemService(WIFI_SERVICE);                if (wifiManager.isWifiEnabled()){                    wifiManager.setWifiEnabled(false);                    Toast.makeText(MainActivity.this, "WiFi已关闭", Toast.LENGTH_SHORT).show();                }else{                    wifiManager.setWifiEnabled(true);                    Toast.makeText(MainActivity.this, "WiFi已打开", Toast.LENGTH_SHORT).show();                }                break;            case R.id.voice:                AudioManager audioManager = (AudioManager) MainActivity.this.getSystemService(AUDIO_SERVICE);                int max = audioManager.getStreamMaxVolume(AudioManager.STREAM_SYSTEM);                int current = audioManager.getStreamVolume(AudioManager.STREAM_RING);                Toast.makeText(MainActivity.this, "最大音量" + max + "当前音量" + current, Toast.LENGTH_SHORT).show();                break;            case R.id.packagename:                ActivityManager activityManager = (ActivityManager) MainActivity.this.getSystemService(ACTIVITY_SERVICE);                String packageName = activityManager.getRunningTasks(1).get(0).topActivity.getPackageName();                Toast.makeText(MainActivity.this, "当前应用程序包名：" + packageName, Toast.LENGTH_SHORT).show();                break;        }    }    //获取网络状态 判断是否已连接网络    public boolean isNetwork(Context context){        if (context != null){            ConnectivityManager manager = (ConnectivityManager) context.getSystemService(CONNECTIVITY_SERVICE);            NetworkInfo networkInfo = manager.getActiveNetworkInfo();            if (networkInfo != null){                return manager.isActiveNetworkMetered();            }        }        return false;    }}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.superxingyun.systemservicedemo">    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>    <uses-permission android:name ="android.permission.CHANGE_NETWORK_STATE"/>    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>    <uses-permission android:name="android.permission.GET_TASKS"/>    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:supportsRtl="true"        android:theme="@style/Theme.AppCompat.Light.NoActionBar">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>

布局文件
activity_main.xml

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.superxingyun.systemservicedemo.MainActivity">    <Button        android:onClick="doClick"        android:id="@+id/network"        android:layout_width="match_parent"        android:text="@string/network"        android:layout_height="wrap_content" />    <Button        android:onClick="doClick"        android:id="@+id/fouthG"        android:layout_width="match_parent"        android:text="@string/_4g"        android:layout_height="wrap_content"        android:layout_below="@+id/network"/>    <Button        android:onClick="doClick"        android:id="@+id/wifi"        android:layout_width="match_parent"        android:text="@string/wifi"        android:layout_height="wrap_content"        android:layout_below="@+id/fouthG"/>    <Button        android:onClick="doClick"        android:id="@+id/voice"        android:layout_width="match_parent"        android:text="@string/getvoice"        android:layout_height="wrap_content"        android:layout_below="@+id/wifi"/>    <Button        android:onClick="doClick"        android:id="@+id/packagename"        android:layout_width="match_parent"        android:text="@string/packagename"        android:layout_height="wrap_content"        android:layout_below="@+id/voice"/></RelativeLayout>