浩做编程方式锁住我的Andr​​oid手机？ 我想下面的这个的例子。但是，当我点击启用按钮活动弹出的几毫秒后自动关闭

Ho do i lock my android phone programmatically ? I tried following this example. But when i click on the enable button the Activity pops up for few milliseconds and then closes automatically

日志显示没有错误只是这个日志

The log shows no error just this log

 Log.i("DeviceAdminSample", "Admin enable FAILED!");

任何人能告诉我如何锁定屏幕的Andr​​oid（如锁时做出许多尝试的模式锁，手机锁下）

Can any one tell me how to lock the android screen (Like the lock when make to many attempts in pattern lock and the phone locks down)

任何帮助是pciated AP $ P $

Any help is appreciated

推荐答案

您必须使您的应用程序作为管理员，了解这里有什么事

You have to make your app as admin, Read something over here

创建一个新的空项目，并创建了一个名为 MyAdminReceiver 扩展 DeviceAdminReceiver 像这样

Create a new empty project and create a class called MyAdminReceiver that extends DeviceAdminReceiver like this

import android.app.admin.DeviceAdminReceiver;

public class MyAdminReceiver extends DeviceAdminReceiver{

}

创建一个名为XML的新的文件夹，并创建一个.xml文件名为您的管理员权限 admin.xml的并添加策略，在你情况下，它锁定屏幕

Create a new folder called xml and create an .xml file for your admin rights called admin.xml and add the policies, in you case its locking the screen

<device-admin xmlns:android="http://schemas.android.com/apk/res/android" >
    <uses-policies>
        <force-lock />
    </uses-policies>
</device-admin>

在您的清单下的应用程序添加标签的接收器

In your manifest add the receiver under Application tag

<receiver
    android:name="MyAdminReceiver"
    android:permission="android.permission.BIND_DEVICE_ADMIN">
    <meta-data
        android:name="android.app.device_admin"
        android:resource="@xml/admin"/>

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

而在你的 MainActivity.java 添加code这样

import android.app.Activity;
import android.app.admin.DevicePolicyManager;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

    private static final int ADMIN_INTENT = 15;
    private static final String description = "Some Description About Your Admin";
    private DevicePolicyManager mDevicePolicyManager; 
    private ComponentName mComponentName;  

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mDevicePolicyManager = (DevicePolicyManager)getSystemService(  
                  Context.DEVICE_POLICY_SERVICE);  
        mComponentName = new ComponentName(this, MyAdminReceiver.class);  
        Button btnEnableAdmin = (Button) findViewById(R.id.btnEnableAdmin);
        Button btnDisableAdmin = (Button) findViewById(R.id.btnDisableAdmin);
        Button btnLock = (Button) findViewById(R.id.btnLock);
        btnEnableAdmin.setOnClickListener(this);
        btnDisableAdmin.setOnClickListener(this);
        btnLock.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.btnEnableAdmin:
            Intent intent = new Intent(DevicePolicyManager.ACTION_ADD_DEVICE_ADMIN);
            intent.putExtra(DevicePolicyManager.EXTRA_DEVICE_ADMIN, mComponentName);
            intent.putExtra(DevicePolicyManager.EXTRA_ADD_EXPLANATION,description);
            startActivityForResult(intent, ADMIN_INTENT);
        break;

        case R.id.btnDisableAdmin:
            mDevicePolicyManager.removeActiveAdmin(mComponentName);  
            Toast.makeText(getApplicationContext(), "Admin registration removed", Toast.LENGTH_SHORT).show();
        break;

        case R.id.btnLock:
             boolean isAdmin = mDevicePolicyManager.isAdminActive(mComponentName);  
             if (isAdmin) {  
                 mDevicePolicyManager.lockNow();  
             }else{
                 Toast.makeText(getApplicationContext(), "Not Registered as admin", Toast.LENGTH_SHORT).show();
             }
        break;
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == ADMIN_INTENT) {
            if (resultCode == RESULT_OK) {
                Toast.makeText(getApplicationContext(), "Registered As Admin", Toast.LENGTH_SHORT).show();
            }else{
                Toast.makeText(getApplicationContext(), "Failed to register as Admin", Toast.LENGTH_SHORT).show();
            }
        }
    }

}

注意：如果您尝试调用意向管理设备等，从一个活动的子类有机会，你可能会使用一个错误 Intent.FLAG_ACTIVITY_NEW_TASK 但是当你用你的窗口可能不会弹出像你的情况，以便尝试从活动的子类，打开它只是

Note: If you try to call the Intent for Admin Device other that from an Activity subclass there are chances you might get an error to use Intent.FLAG_ACTIVITY_NEW_TASK but when you use that your window might not pop like in your case so Try opening it from a subclass of an activity only

你也不能卸载你的应用程序，除非它没有被注销，因为管理

Also you cannot un-install your app unless it has not be unregistered as an admin