系统组件-锁屏应用

package com.xfeng.onekeylock;

import android.app.admin.DevicePolicyManager;
import android.content.ComponentName;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    DevicePolicyManager devicePolicyManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        devicePolicyManager = (DevicePolicyManager) getSystemService(DEVICE_POLICY_SERVICE);
        findViewById(R.id.btnLockScreen).setOnClickListener(this);
        findViewById(R.id.btnRegDeviceAdmin).setOnClickListener(this);
        findViewById(R.id.btnUnregDeviceAdmin).setOnClickListener(this);

    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.btnLockScreen:
                devicePolicyManager.lockNow();
                break;

            case R.id.btnRegDeviceAdmin:

                Intent i = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
                i.putExtra(devicePolicyManager.EXTRA_DEVICE_ADMIN,new ComponentName(this,DeviceManagerBc.class));
                startActivity(i);

                System.out.println("!!!!!");

                break;

            case R.id.btnUnregDeviceAdmin:
                devicePolicyManager.removeActiveAdmin(new ComponentName(this,DeviceManagerBc.class));
                System.out.println("!!3!!");
                break;

            default:
                break;
        }
    }
}

package com.xfeng.onekeylock;

import android.app.admin.DeviceAdminReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

/**
 * Created by xiaofeng on 15/12/30.
 */
public class DeviceManagerBc extends DeviceAdminReceiver {

    @Override
    public void onEnabled(Context context, Intent intent) {
        super.onEnabled(context, intent);
        Toast.makeText(context,"已经注册成为系统组件",Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onDisabled(Context context, Intent intent) {
        super.onDisabled(context, intent);
        Toast.makeText(context,"已经注销了系统组件",Toast.LENGTH_SHORT).show();
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    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"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="需要获取设备管理者权限才能拥有锁屏功能"/>
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="注册成为系统组件"
        android:id="@+id/btnRegDeviceAdmin"/>
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="注销系统组件"
        android:id="@+id/btnUnregDeviceAdmin"/>
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="锁屏"
        android:id="@+id/btnLockScreen"/>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<device-admin xmlns:android="http://schemas.android.com/apk/res/android">
    <uses-policies>
        <force-lock />
    </uses-policies>
</device-admin>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.xfeng.onekeylock">

    android:permission="android.permission.BIND_DEVICE_ADMIN"
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <receiver
            android:name=".DeviceManagerBc" >
            <meta-data
                android:name="android.app.device_admin"
                android:resource="@xml/device_admin" />
            <intent-filter>
                <action android:name="android.app.action.DEVICE_ADMIN_ENABLED" />

            </intent-filter>
        </receiver>

    </application>

</manifest>