android - 尽管已授予权限，但仍获得安全异常

Question

我的应用程序未获得 android.permission.WRITE_SETTINGS 授权时出现 java.lang.SecurityException。即使我已将它添加到我的 list xml 文件中

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

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity android:name=".SoundActivity1"></activity>
</application>

<uses-permission android:name="android.permission.VIBRATE"/>
<uses-permission android:name="android.permission.WRITE_SETTINGS"/>

编辑 1:好的，所以我有这段代码必须在 Activity 之外的类中运行，我将如何请求用户许可，然后如果他们授予它，运行这段代码，全部在一个类中 Activity 之外？ -

Uri newRingtone = Uri.parse("android.resource://com.example.myapp/" + soundID); 
RingtoneManager.setActualDefaultRingtoneUri(context,RingtoneManager.TYPE_RINGTONE,newRingtone);

在任何人问之前，是的，它需要在我设置我的应用程序的 Activity 之外

Answer 1

根据 WRITE_SETTINGS documentation :

Note: If the app targets API level 23 or higher, the app user must explicitly grant this permission to the app through a permission management screen. The app requests the user's approval by sending an intent with action ACTION_MANAGE_WRITE_SETTINGS. The app can check whether it has this authorization by calling Settings.System.canWrite().

因此您应该使用如下代码:

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M &&
    !Settings.System.canWrite(this)) {
  Intent intent = new Intent(Settings.ACTION_MANAGE_WRITE_SETTINGS);
  intent.setData("package:"+getPackageName());
  startActivityForResult(intent);
  // now wait for onActivityResult()
}