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我无法使用“requestPermissionLauncher.launch(permissions)”显示权限窗口

permissions android

Deusnominus · 技术社区 · 2 年前

我正在尝试请求我的应用程序所需的权限,但无法显示权限窗口。这是我的堆肥:

@Composable
fun IntroScreen(
    introViewModel: IntroViewModel = hiltViewModel(),
    navController: NavController
){

    val requestPermissionLauncher = rememberLauncherForActivityResult(
        ActivityResultContracts.RequestMultiplePermissions()
    ) { permissionsMap ->
        permissionsMap.forEach { (permission, isGranted) ->
            Log.i("tag", "Permission: $permission, Granted: $isGranted")
        }
    }

    val permissions = introViewModel.permissions
    val permissionsState by introViewModel.permissionsState.collectAsState()

    Column(
        modifier = Modifier
            .fillMaxWidth(),
        verticalArrangement = Arrangement.Center,
        horizontalAlignment = Alignment.CenterHorizontally

    ){
        Button(onClick = {
            Log.i("tag", "Permissions state: ${permissionsState.joinToString(separator = ", ")}")
            val allPermissionsGranted = permissionsState.all { it }
            Log.i("tag", "All permissions granted: $allPermissionsGranted")

            if (!allPermissionsGranted) {
                // Request permissions
                Log.i("tag", "Requesting permissions inside if statement: ${permissions.joinToString(", ")}")
                requestPermissionLauncher.launch(permissions)
            } else {
                Log.i("tag", "All permissions already granted")
            }
       }, shape = Shapes.small) {
            Text(text = "Ask Permissions")

    }
}

以下是我的视图模型:

@HiltViewModel
class IntroViewModel @Inject constructor(private val context: Context, introInteractor:IntroInteractor):ViewModel(){

    private val _permissionsState = MutableStateFlow(emptyList<Boolean>())
    val permissionsState: StateFlow<List<Boolean>> get() = _permissionsState

    val permissions = arrayOf(
        Manifest.permission.ACCESS_COARSE_LOCATION,
        Manifest.permission.ACCESS_FINE_LOCATION,
        Manifest.permission.ACCESS_BACKGROUND_LOCATION,
        Manifest.permission.BLUETOOTH,
        Manifest.permission.BLUETOOTH_ADMIN,
        Manifest.permission.BLUETOOTH_SCAN,
        Manifest.permission.BLUETOOTH_ADVERTISE,
        Manifest.permission.POST_NOTIFICATIONS,
        Manifest.permission.CAMERA,
        Manifest.permission.INTERNET
    )

    init {
        updatePermissionsState()
    }

    fun updatePermissionsState() {
        val permissionsStateList = permissions.map { permission ->
            ContextCompat.checkSelfPermission(context, permission) == PackageManager.PERMISSION_GRANTED
        }
        _permissionsState.value = permissionsStateList
    }
}

我尽可能地简化了代码。所有记录的语句都返回预期的结果。互联网、蓝牙和蓝牙权限为真,其余为假。我试着删除那些是真的,但我没有让窗口出现。我的代码到达“requestPermissionLauncher.launch(permissions)”,launch()的参数正确。为什么我不能让窗户出现?

这是我启动器前if语句中的日志结果: “在if语句中请求权限:android.permission.ACCES_CARSE_LOCATION,android.prmission.ACCESS_FINE_LOCATION、android.pemission.ACCESS_BACKGROUND_LOCATION和android.ppermission.BLUETOOTH,android.permission.BLUETTOTH_SCAN,android.permission.BLUETOOTH_AVERTISE,android_permission.POST_NOTIFICATIONS,android.permission.CAMERA,android_permission.INTERNET ".

注意:我正在测试一个真正的Galaxy A14,我的清单文件是:

<uses-permission android:name="android.permission.FOREGROUND_SERVICE"/>
<uses-permission android:name="android.permission.FOREGROUND_SERVICE_SPECIAL_USE"/>
<uses-permission android:name="android.permission.POST_NOTIFICATIONS"/>

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

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />


<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
<uses-feature android:name="android.hardware.bluetooth_le" android:required="true"/>

<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" android:required="false"/>

1 回复 | 直到 2 年前

NehaK 2 年前

看起来您已经正确设置了权限请求逻辑,但权限对话框没有出现。以下是可能发生这种情况的一些潜在原因以及如何解决它们:

1.检查Android版本兼容性

后台位置权限:在运行的设备上 Android 10 (API level 29) and higher ,请求后台位置权限( ACCESS_BACKGROUND_LOCATION )应在前台位置权限后单独完成( ACCESS_FINE_LOCATION 和 ACCESS_COARSE_LOCATION )被授予。同时请求所有位置权限可能会导致对话框不显示。

解决方案:在授予前台位置权限后,尝试在单独的调用中请求后台位置权限。

if (permissionsState[0] && permissionsState[1]) { // Assuming these indices are for ACCESS_FINE_LOCATION and ACCESS_COARSE_LOCATION
    requestPermissionLauncher.launch(arrayOf(Manifest.permission.ACCESS_BACKGROUND_LOCATION))
}

2.Android 13上的POST_NOTIFICATIONS权限(API 33)

这个 POST_NOTIFICATIONS 仅在Android 13(API 33级)及更高版本上需要权限。如果您在API级别较低的设备上进行测试,则可能不需要此权限,尝试请求此权限可能会导致问题。解决方案:确保 POST_通知 仅在Android 13+设备上请求权限。

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
    requestPermissionLauncher.launch(arrayOf(Manifest.permission.POST_NOTIFICATIONS))
}

3.已授予或永久拒绝的权限

如果之前授予或永久拒绝了权限(使用“不再询问”选项),则不会出现对话框。相反,您应该引导用户进入应用程序的设置,以手动启用权限。

解决方案:检查是否有任何权限被永久拒绝,并相应地处理。

val shouldShowRequestPermissionRationale = permissions.any { permission ->
    ActivityCompat.shouldShowRequestPermissionRationale(activity, permission)
}
if (!shouldShowRequestPermissionRationale) {
    // Guide the user to the app's settings
}

我希望这能有所帮助。