1.创建创建一类继承DeviceAdminReceiver

public class Admin extends DeviceAdminReceiver {

}

2.清单文件配置

<receiver
            android:name="com.example.locknow.Admin"
            android:description="@string/sample_device_admin_description"
            android:label="@string/sample_device_admin"
            android:permission="android.permission.BIND_DEVICE_ADMIN" >
            <meta-data
                android:name="android.app.device_admin"
                android:resource="@xml/device_admin_sample" />


            <intent-filter>
                <action android:name="android.app.action.DEVICE_ADMIN_ENABLED" />
            </intent-filter>
</receiver>

3.在res->xml->device_admin_sample.xml,同时修改描述信息,标题等信息

<device-admin xmlns:android="http://schemas.android.com/apk/res/android">
 <uses-policies>
   <limit-password />
   <watch-login />
   <reset-password />
   <force-lock />
   <wipe-data />
   <expire-password />
   <encrypted-storage />
   <disable-camera />
 </uses-policies>
</device-admin>

4.激活 setting -> security -> device admin...

5.代码激活超级管理员

   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
//        setContentView(R.layout.activity_main);
        devicePolicyManager = (DevicePolicyManager) getSystemService(DEVICE_POLICY_SERVICE);
        componentName = new ComponentName(this, admin.class);
        if (devicePolicyManager.isAdminActive(componentName)) {
            devicePolicyManager.lockNow();
          finish();
        }
    }
public void register(View v){
//代码激活超级管理员
//设置激活超级管理员
Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
//设置激活那个超级管理员
//mDeviceAdminSample : 超级管理员的标示
        intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, componentName);
        //设置描述信息
        intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION,"一键锁屏,非常好用");
        startActivity(intent);
}

6.代码注销超级管理员

public void delete(View v){
//注销超级管理员
//判断超级管理员是否激活
if (devicePolicyManager.isAdminActive(componentName)) {
//注销超级管理员
devicePolicyManager.removeActiveAdmin(componentName);
}
}

7.锁屏操作

public void locknow(View v){
//锁屏的操作
devicePolicyManager.lockNow();//锁屏
}