java - 为什么isLockTaskPermitted标志为false

我正在尝试以编程方式在Android L上固定屏幕。
我的应用程序包含带有

<?xml version="1.0" encoding="utf-8"?>
<device-admin xmlns:android="http://schemas.android.com/apk/res/android">
    <uses-policies>
        <force-lock/>
        <watch-login/>
        <disable-camera/>
        <disable-keyguard-features/>
        <encrypted-storage/>
        <expire-password/>
        <limit-password/>
        <reset-password/>
        <set-global-proxy/>
        <wipe-data/>
    </uses-policies>
</device-admin>

我在定义AdminReceiver的AndroidManifest文件中使用正确的行安装了应用程序。
几周前一切正常，但是现在当我回到这个项目时-App要求我在每次启动时都确认“Pin screen”弹出窗口。

当我调试时，我注意到奇怪的行为devicePolicyManager.isAdminActive(componentName)为truedevicePolicyManager.isDeviceOwnerApp(getPackageName())为true

但
devicePolicyManager.isLockTaskPermitted(getPackageName())为假

我是否使用adb推荐的dpm set-device-owner ...或将device_owner.xml文件推送到/data/system/将应用程序设置为设备所有者都没有关系

我的问题是为什么应用程序无权锁定屏幕？

最佳答案

为此，您必须调用 setLockTaskPackages()

您的代码应如下所示。

您的 Activity 应具有

ComponentName mAdminComponentName = DeviceAdminReceiver.getComponentName(this);
//where this will be your Activity

DevicePolicyManager mDevicePolicyManager = (DevicePolicyManager)
                getSystemService(Context.DEVICE_POLICY_SERVICE);

mDevicePolicyManager.setLockTaskPackages(mAdminComponentName,new String[]{getPackageName()});

DeviceAdminReceiver.java

// Copyright 2016 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package com.google.codelabs.cosu;

/**
 * Created by nyfuchs on 4/26/16.
 */

import android.content.ComponentName;
import android.content.Context;

/**
 * Handles events related to the managed profile.
 */
public class DeviceAdminReceiver extends android.app.admin.DeviceAdminReceiver {
    private static final String TAG = "DeviceAdminReceiver";

    /**
     * @param context The context of the application.
     * @return The component name of this component in the given context.
     */
    public static ComponentName getComponentName(Context context) {
        return new ComponentName(context.getApplicationContext(), DeviceAdminReceiver.class);
    }
}

AndroidManifest.xml

    <receiver
        android:name="com.google.codelabs.cosu.DeviceAdminReceiver"
        android:description="@string/app_name"
        android:label="@string/app_name"
        android:permission="android.permission.BIND_DEVICE_ADMIN">
        <meta-data
            android:name="android.app.device_admin"
            android:resource="@xml/device_admin_receiver" />
        <intent-filter>
            <action android:name="android.intent.action.DEVICE_ADMIN_ENABLED"/>
            <action android:name="android.intent.action.PROFILE_PROVISIONING_COMPLETE"/>
            <action android:name="android.intent.action.BOOT_COMPLETED"/>
        </intent-filter>
    </receiver>

关于java - 为什么isLockTaskPermitted标志为false，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/36908595/