（转）Android 设备管理员 锁屏

转自：http://labs.chinamobile.com/mblog/532767_73990

 

Android 2.2 SDK提供了一个可管理和操作设备的API叫DevicePolicyManager，使用这个API你可以接管手机的应用权限，对手机做出很多大胆的操作，比如锁屏，恢复出厂设置（这么和谐的东西要是在中国是不大可能提供给你的），还有设置密码、强制清除密码，修改密码、设置屏幕灯光渐暗时间间隔等操作。这个API可谓是直接可以将你做的应用程序变成系统的老大哥了。虽说是这样，但应用程序可做老大只是对于你本身应用程序有效，别人也可以做类似的应用程序，这个与别人的权限是不起冲突的。

好了，废话不说，上界面：

 

 

具体的编写代码的流程：

1.因为这个API是用的2.2提供的API，所以必须将sdkVersion设置为8，像这样<uses-sdk android:minSdkVersion="8" />，这是必须的。

2.注册一个广播服务类，用以监听权限的变化：


<receiver android:name=".deviceAdminReceiver" android:label="@string/app_name"
android:description="@string/description" android:permission="android.permission.BIND_DEVICE_ADMIN">

<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>



android:permission 表示此功能需要的权限，android:name="android.app.action.DEVICE_ADMIN_ENABLED" 表示此动作的跳转界面

<meta-data android:name="android.app.device_admin"
android:resource="@xml/device_admin" />
表示这个应用可以管理的权限清单，xml清单如下：


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






广播服务类的JAVA代码，重写一些必要的实现函数：


package com.terry.device;

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

public class deviceAdminReceiver extends DeviceAdminReceiver {

/**
* 获取设备存储的数值
*
* @param context
* @return
*/
public static SharedPreferences getDevicePreference(Context context) {
return context.getSharedPreferences(
DeviceAdminReceiver.class.getName(), 0);
}

// 密码的特点
public static String PREF_PASSWORD_QUALITY = "password_quality";
// 密码的长度
public static String PREF_PASSWORD_LENGTH = "password_length";

public static String PREF_MAX_FAILED_PW = "max_failed_pw";

void showToast(Context context, CharSequence text) {
Toast.makeText(context, text, Toast.LENGTH_SHORT).show();
}

@Override
public void onEnabled(Context context, Intent intent) {
// TODO Auto-generated method stub
showToast(context, "设备管理：可用");
}

@Override
public void onDisabled(Context context, Intent intent) {
// TODO Auto-generated method stub
showToast(context, "设备管理：不可用");
}

@Override
public CharSequence onDisableRequested(Context context, Intent intent) {
// TODO Auto-generated method stub
return "这是一个可选的消息，警告有关禁止用户的请求";
}

@Override
public void onPasswordChanged(Context context, Intent intent) {
// TODO Auto-generated method stub
showToast(context, "设备管理：密码己经改变");
}

@Override
public void onPasswordFailed(Context context, Intent intent) {
// TODO Auto-generated method stub
showToast(context, "设备管理：改变密码失败");
}

@Override
public void onPasswordSucceeded(Context context, Intent intent) {
// TODO Auto-generated method stub
showToast(context, "设备管理：改变密码成功");
}

}





DeviceAdminReceiver是扩展于BroadcastReceiver。



下面先来看看操作效果，点击启用管理：

 

 

 

数据显示不完全 ，往下拉将看到：

 

 

 

中间有一句话叫做：“设备管理可以对系统的一些安全进行设置”，这句话来源于上面的广播receiver中的description:android:description="@string/description"，点击激活会触发广播类响应上面广播类弹出Toast。启用管理代码：

/**
* 设备管理可用的点击事件
*
* @author terry
*
*/
class enableAdminClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(
DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN,
mDeviceComponentName);
intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION,
"这里可以输入一些额外的说明,比如提示用户什么的");
startActivityForResult(intent, RESULT_ENABLE);
}

}






锁屏操作，由于是模拟器不能做到真正错屏，只能停到初始模拟器进来需要解锁的状态，屏幕不会变暗。锁屏代码：


/**
* 锁屏
*
* @author terry
*
*/
class force_lock implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mAM.isUserAMonkey()) {
AlertDialog.Builder builder = new AlertDialog.Builder(
deviceActivity.this);
builder.setMessage("你不能对此屏幕进行操作，因为你不是管理员");
builder.setPositiveButton("I admit defeat", null);
builder.show();
return;
}
boolean active = mDPM.isAdminActive(mDeviceComponentName);
if (active) {
mDPM.lockNow();
}
}
}





屏幕在设置相应时间后灯光变暗效果：


/**
* 屏幕自动变暗
*
* @author terry
*
*/
class timeoutClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mAM.isUserAMonkey()) {
AlertDialog.Builder builder = new AlertDialog.Builder(
deviceActivity.this);
builder.setMessage("你不能对我的屏幕进行操作，因为你不是管理员");
builder.setPositiveButton("I admit defeat", null);
builder.show();
return;
}
boolean active = mDPM.isAdminActive(mDeviceComponentName);
if (active) {
long timeout = 1000L * Long.parseLong(et.getText().toString());
mDPM.setMaximumTimeToLock(mDeviceComponentName, timeout);
}
}
}





由于是模拟器，恢复出厂设置清除数据后，将无法重新开机，必须重新启动机子，在真机上是没有问题的，测试的时候必须小心，以免将你的数据清除掉。恢复出厂设置代码：


/**
* 恢复出厂设置
*
* @author terry
*
*/
class resetClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mAM.isUserAMonkey()) {
// Don't trust monkeys to do the right thing!
AlertDialog.Builder builder = new AlertDialog.Builder(
deviceActivity.this);
builder
.setMessage("You can't wipe my data because you are a monkey!");
builder.setPositiveButton("I admit defeat", null);
builder.show();
return;
}

AlertDialog.Builder builder = new Builder(deviceActivity.this);
builder.setMessage("将重置数据，你确定此操作吗？");
builder.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {

@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
AlertDialog.Builder aler = new AlertDialog.Builder(
deviceActivity.this);
aler.setMessage("删除数据后，系统将会重新启动.确定吗？");
aler.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {

@Override
public void onClick(
DialogInterface dialog,
int which) {
// TODO Auto-generated method stub
boolean active = mDPM
.isAdminActive(mDeviceComponentName);
if (active) {
mDPM.wipeData(0);
}
}
});
aler
.setNeutralButton(android.R.string.cancel,
null);
aler.show();
}
});
builder.setNeutralButton(android.R.string.cancel, null);
builder.show();
}
}



API的提供简化了很多烦琐的操作，就上面那些代码就可以实现了，完整代码如下：


DeviceActivity
package com.terry.device;

import android.app.Activity;
import android.app.ActivityManager;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.app.admin.DevicePolicyManager;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;

public class deviceActivity extends Activity {
static final int RESULT_ENABLE = 1;
DevicePolicyManager mDPM;
ActivityManager mAM;
ComponentName mDeviceComponentName;
Button enableAdmin, disableAdmin, force_lock, btn_time_out, reset;
EditText et;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

mDPM = (DevicePolicyManager) getSystemService(Context.DEVICE_POLICY_SERVICE);
mAM = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE);
mDeviceComponentName = new ComponentName(deviceActivity.this,
deviceAdminReceiver.class);
setContentView(R.layout.main);

findView();

init();

}

void findView() {
enableAdmin = (Button) findViewById(R.id.enable_admin);
disableAdmin = (Button) findViewById(R.id.disable_admin);
force_lock = (Button) findViewById(R.id.force_lock);
btn_time_out = (Button) findViewById(R.id.time_out);
et = (EditText) findViewById(R.id.et_time_out);
reset = (Button) findViewById(R.id.reset);
}

void init() {
enableAdmin.setOnClickListener(new enableAdminClickEvent());
disableAdmin.setOnClickListener(new disableAdminClickEvent());
force_lock.setOnClickListener(new force_lock());
btn_time_out.setOnClickListener(new timeoutClickEvent());
reset.setOnClickListener(new resetClickEvent());
}

void updateButtonState() {
boolean active = mDPM.isAdminActive(mDeviceComponentName);
if (active) {
enableAdmin.setEnabled(false);
disableAdmin.setEnabled(true);
force_lock.setEnabled(true);
btn_time_out.setEnabled(true);
reset.setEnabled(true);
} else {
enableAdmin.setEnabled(true);
disableAdmin.setEnabled(false);
force_lock.setEnabled(false);
btn_time_out.setEnabled(false);
reset.setEnabled(false);
}
}

@Override
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
updateButtonState();
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
switch (requestCode) {
case RESULT_ENABLE:
if (resultCode == Activity.RESULT_OK) {
Log.v("DeviceEnable", "deviceAdmin:enable");
} else {
Log.v("DeviceEnable", "deviceAdmin:disable");
}
break;

}

super.onActivityResult(requestCode, resultCode, data);
}

/**
* 设备管理可用的点击事件
*
* @author terry
*
*/
class enableAdminClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent(
DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN,
mDeviceComponentName);
intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION,
"这里可以输入一些额外的说明,比如提示用户什么的");
startActivityForResult(intent, RESULT_ENABLE);
}

}

/**
* 设备管理不可用的点击事件
*
* @author terry
*
*/
class disableAdminClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
mDPM.removeActiveAdmin(mDeviceComponentName);
updateButtonState();
}

}

/**
* 锁屏
*
* @author terry
*
*/
class force_lock implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mAM.isUserAMonkey()) {
AlertDialog.Builder builder = new AlertDialog.Builder(
deviceActivity.this);
builder.setMessage("你不能对此屏幕进行操作，因为你不是管理员");
builder.setPositiveButton("I admit defeat", null);
builder.show();
return;
}
boolean active = mDPM.isAdminActive(mDeviceComponentName);
if (active) {
mDPM.lockNow();
}
}
}

/**
* 屏幕自动变暗
*
* @author terry
*
*/
class timeoutClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mAM.isUserAMonkey()) {
AlertDialog.Builder builder = new AlertDialog.Builder(
deviceActivity.this);
builder.setMessage("你不能对我的屏幕进行操作，因为你不是管理员");
builder.setPositiveButton("I admit defeat", null);
builder.show();
return;
}
boolean active = mDPM.isAdminActive(mDeviceComponentName);
if (active) {
long timeout = 1000L * Long.parseLong(et.getText().toString());
mDPM.setMaximumTimeToLock(mDeviceComponentName, timeout);
}
}
}

/**
* 恢复出厂设置
*
* @author terry
*
*/
class resetClickEvent implements OnClickListener {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (mAM.isUserAMonkey()) {
// Don't trust monkeys to do the right thing!
AlertDialog.Builder builder = new AlertDialog.Builder(
deviceActivity.this);
builder
.setMessage("You can't wipe my data because you are a monkey!");
builder.setPositiveButton("I admit defeat", null);
builder.show();
return;
}

AlertDialog.Builder builder = new Builder(deviceActivity.this);
builder.setMessage("将重置数据，你确定此操作吗？");
builder.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {

@Override
public void onClick(DialogInterface dialog, int which) {
// TODO Auto-generated method stub
AlertDialog.Builder aler = new AlertDialog.Builder(
deviceActivity.this);
aler.setMessage("删除数据后，系统将会重新启动.确定吗？");
aler.setPositiveButton(android.R.string.ok,
new DialogInterface.OnClickListener() {

@Override
public void onClick(
DialogInterface dialog,
int which) {
// TODO Auto-generated method stub
boolean active = mDPM
.isAdminActive(mDeviceComponentName);
if (active) {
mDPM.wipeData(0);
}
}
});
aler
.setNeutralButton(android.R.string.cancel,
null);
aler.show();
}
});
builder.setNeutralButton(android.R.string.cancel, null);
builder.show();
}
}

}