根据这个:http://developer.android.com/preview/features/runtime-permissions.html#coding一个应用程序可以检查运行时权限和请求权限，如果它还没有被授予。弹出如下对话框:
如果用户拒绝一个重要的权限，在我看来，应用程序应该显示一个解释为什么需要权限和什么影响拒绝。该对话框有两个选项:
重试(再次请求许可) 拒绝(应用程序将工作没有该许可)。
但是，如果用户选中“Never ask again”，则不应该显示带有解释的第二个对话框，特别是如果用户之前已经拒绝了一次。 现在的问题是:我的应用程序如何知道用户是否选中了Never ask again?IMO onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)没有给我这个信息。
第二个问题是:谷歌是否计划在权限对话框中包含一个自定义消息，以解释为什么应用程序需要权限?这样就不会出现第二个对话框，这肯定会带来更好的用户体验。
当前回答
这个示例演示了当用户选择“拒绝&不要再次询问”时如何处理
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
registerStoragePermission()
registerGalleryLauncher()
registerCameraPermission()
registerCameraLauncher()
}
private fun registerCameraPermission() {
requestCameraPermissionLauncher =
registerForActivityResult(ActivityResultContracts.RequestPermission()) { granted ->
if (granted) {
Log.d(TAG, "registerCameraPermission - Camera Permission Granted")
openCamera()
} else {
Log.d(TAG, "registerCameraPermission - Camera Permission NOT Granted")
requestCameraPermission()
}
}
}
private fun registerStoragePermission() {
requestStoragePermissionLauncher =
registerForActivityResult(ActivityResultContracts.RequestPermission()) { granted ->
if (granted) {
Log.d(TAG, "registerStoragePermission - Storage Permission Granted")
viewGallery()
} else {
Log.d(TAG, "registerStoragePermission - Storage Permission NOT Granted")
requestStoragePermission()
}
}
}
private fun registerCameraLauncher() {
cameraLauncher =
registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
val data: Intent? = result.data
if (data == null) {
return@registerForActivityResult
}
val extras = data.extras
imageBitmap = extras!!["data"] as Bitmap
file = FileUtils.createFile(requireContext(),
getString(R.string.app_name),
"my_profile_image.png"
)
//FileUtils.saveBitmap(imageBitmap, file);
val imageLocalPath = FileUtils.saveImageToInternalStorage(file, imageBitmap)
SharedPreferencesUtils.setProfilePath(requireActivity(), imageLocalPath)
profileFragmentBinding.imageViewCircleNoStroke.setImageBitmap(imageBitmap)
profileFragmentBinding.imageViewCircleNoStroke.setScaleType(ImageView.ScaleType.CENTER_CROP)
}
}
}
private fun registerGalleryLauncher() {
galleryLauncher =
registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
val data: Intent? = result.data
if (data == null) {
return@registerForActivityResult
}
val uri = data.data
var imageLocalPath = File(FileUtils.getPathReal(requireActivity(), uri!!))
file = imageLocalPath.absoluteFile
SharedPreferencesUtils.setProfilePath(requireActivity(), imageLocalPath.absolutePath)
Glide.with(requireActivity()).load(uri)
.into(profileFragmentBinding.imageViewCircleNoStroke)
profileFragmentBinding.imageViewCircleNoStroke.setScaleType(ImageView.ScaleType.CENTER_CROP)
}
}
}
private fun showImageUploadOptions() {
val mDialog = activity.let { Dialog(it!!) }
mDialog.requestWindowFeature(Window.FEATURE_NO_TITLE)
mDialog.setContentView(R.layout.dialog_profile_image_option)
mDialog.window!!.setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))
//val mAlertMessageTv = mDialog.findViewById<View>(R.id.id_alert_tv) as TextView
//mAlertMessageTv.text = message
galleryLl = mDialog.findViewById<View>(R.id.id_gallery_ll) as LinearLayout
cameraLl = mDialog.findViewById<View>(R.id.id_camera_ll) as LinearLayout
removePhotoLl = mDialog.findViewById<View>(R.id.id_remove_photo_ll) as LinearLayout
galleryLl.setOnClickListener {
CallStoragePermission()
mDialog.dismiss()
}
cameraLl.setOnClickListener {
CallCameraPermission()
mDialog.dismiss()
}
removePhotoLl.setOnClickListener {
CallRemovePhoto()
mDialog.dismiss()
}
mDialog.setCancelable(true)
mDialog.show()
val metrics = resources.displayMetrics
val width = metrics.widthPixels
val height = metrics.heightPixels
mDialog.window!!.setLayout(
width,
LinearLayout.LayoutParams.WRAP_CONTENT
)
}
fun CallStoragePermission() {
if (!Status_checkReadExternalStoragePermission()) {
requestStoragePermissionLauncher.launch(Manifest.permission.READ_EXTERNAL_STORAGE)
} else {
viewGallery()
}
}
private fun Status_checkReadExternalStoragePermission(): Boolean {
val permissionState = ActivityCompat.checkSelfPermission(
requireActivity(),
Manifest.permission.READ_EXTERNAL_STORAGE
)
return permissionState == PackageManager.PERMISSION_GRANTED
}
private fun requestCameraPermission() {
when {
ContextCompat.checkSelfPermission(
requireContext(),
Manifest.permission.CAMERA
) == PackageManager.PERMISSION_GRANTED -> {
Log.d(TAG, "requestCameraPermission - Camera Permission Granted")
openCamera()
// The permission is granted
// you can go with the flow that requires permission here
}
shouldShowRequestPermissionRationale(Manifest.permission.CAMERA) -> {
// This case means user previously denied the permission
// So here we can display an explanation to the user
// That why exactly we need this permission
Log.d(TAG, "requestCameraPermission - Camera Permission NOT Granted")
showPermissionAlert(
getString(R.string.camera_permission),
getString(R.string.camera_permission_denied),
getString(R.string.ok_caps),
getString(R.string.cancel_caps)
) { requestCameraPermissionLauncher.launch(Manifest.permission.CAMERA) }
}
else -> {
// Everything is fine you can simply request the permission
showPermissionAlert(
getString(R.string.camera_permission),
getString(R.string.camera_permission_denied),
getString(R.string.settings_caps),
getString(R.string.cancel_caps)
) {
val intent = Intent()
intent.action = Settings.ACTION_APPLICATION_DETAILS_SETTINGS
val uri = Uri.fromParts(
"package",
BuildConfig.APPLICATION_ID, null
)
intent.data = uri
intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK
startActivity(intent)
}
}
}
}
private fun requestStoragePermission() {
when {
ContextCompat.checkSelfPermission(
requireContext(),
Manifest.permission.READ_EXTERNAL_STORAGE
) == PackageManager.PERMISSION_GRANTED -> {
Log.d(TAG, "requestStoragePermission - Storage Permission Granted")
viewGallery()
// The permission is granted
// you can go with the flow that requires permission here
}
shouldShowRequestPermissionRationale(Manifest.permission.READ_EXTERNAL_STORAGE) -> {
// This case means user previously denied the permission
// So here we can display an explanation to the user
// That why exactly we need this permission
Log.d(TAG, "requestStoragePermission - Storage Permission NOT Granted")
showPermissionAlert(
getString(R.string.read_storage_permission_required),
getString(R.string.storage_permission_denied),
getString(R.string.ok_caps),
getString(R.string.cancel_caps)
) { requestStoragePermissionLauncher.launch(Manifest.permission.READ_EXTERNAL_STORAGE) }
}
else -> {
// Everything is fine you can simply request the permission
showPermissionAlert(
getString(R.string.read_storage_permission_required),
getString(R.string.storage_permission_denied),
getString(R.string.settings_caps),
getString(R.string.cancel_caps)
) {
val intent = Intent()
intent.action = Settings.ACTION_APPLICATION_DETAILS_SETTINGS
val uri = Uri.fromParts(
"package",
BuildConfig.APPLICATION_ID, null
)
intent.data = uri
intent.flags = Intent.FLAG_ACTIVITY_NEW_TASK
startActivity(intent)
}
}
}
}
private fun showPermissionAlert(
title: String,
message: String,
ok: String,
cancel: String,
function: () -> Unit
) {
val mDialog = requireActivity().let { Dialog(it) }
mDialog.requestWindowFeature(Window.FEATURE_NO_TITLE)
mDialog.setContentView(R.layout.dialog_permission_alert)
mDialog.window!!.setBackgroundDrawable(ColorDrawable(Color.TRANSPARENT))
val mTitleTv = mDialog.findViewById<View>(R.id.id_title_tv) as AppCompatTextView
mTitleTv.text = title
val mMessageTv = mDialog.findViewById<View>(R.id.id_message_tv) as AppCompatTextView
mMessageTv.text = message
val mNoBtn = mDialog.findViewById<View>(R.id.no_btn) as AppCompatTextView
mNoBtn.text = cancel
val mYesBtn = mDialog.findViewById<View>(R.id.yes_btn) as AppCompatTextView
mYesBtn.text = ok
mYesBtn.setOnClickListener {
function.invoke()
mDialog.dismiss()
}
mNoBtn.setOnClickListener { mDialog.dismiss() }
mDialog.setCancelable(true)
mDialog.show()
val metrics = resources.displayMetrics
val width = metrics.widthPixels
val height = metrics.heightPixels
mDialog.window!!.setLayout(
width,
LinearLayout.LayoutParams.WRAP_CONTENT
)
}
fun viewGallery() {
val intentDocument = Intent(Intent.ACTION_GET_CONTENT)
intentDocument.type = "image/*"
intentDocument.putExtra(
Constants.REQUEST_CODE,
Constants.REQUEST_PHOTO_FROM_GALLERY
)
galleryLauncher.launch(intentDocument)
}
fun openCamera() {
val takePictureIntent = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
takePictureIntent.putExtra(
Constants.REQUEST_CODE,
Constants.REQUEST_PERMISSIONS_REQUEST_CODE_CAMERA
)
cameraLauncher.launch(takePictureIntent)
}
fun CallCameraPermission() {
if (!Status_checkCameraPermission()) {
requestCameraPermissionLauncher.launch(Manifest.permission.CAMERA)
} else {
openCamera()
}
}
private fun Status_checkCameraPermission(): Boolean {
val camera = ActivityCompat.checkSelfPermission(
requireActivity(),
Manifest.permission.CAMERA
)
return camera == PackageManager.PERMISSION_GRANTED
}
其他回答
你可以听漂亮。
侦听器
interface PermissionListener {
fun onNeedPermission()
fun onPermissionPreviouslyDenied(numberDenyPermission: Int)
fun onPermissionDisabledPermanently(numberDenyPermission: Int)
fun onPermissionGranted()
}
MainClass的权限
class PermissionUtil {
private val PREFS_FILENAME = "permission"
private val TAG = "PermissionUtil"
private fun shouldAskPermission(context: Context, permission: String): Boolean {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
val permissionResult = ActivityCompat.checkSelfPermission(context, permission)
if (permissionResult != PackageManager.PERMISSION_GRANTED) {
return true
}
}
return false
}
fun checkPermission(context: Context, permission: String, listener: PermissionListener) {
Log.i(TAG, "CheckPermission for $permission")
if (shouldAskPermission(context, permission)) {
// Load history permission
val sharedPreference = context.getSharedPreferences(PREFS_FILENAME, 0)
val numberShowPermissionDialog = sharedPreference.getInt(permission, 0)
if (numberShowPermissionDialog == 0) {
(context as? Activity)?.let {
if (ActivityCompat.shouldShowRequestPermissionRationale(it, permission)) {
Log.e(TAG, "User has denied permission but not permanently")
listener.onPermissionPreviouslyDenied(numberShowPermissionDialog)
} else {
Log.e(TAG, "Permission denied permanently.")
listener.onPermissionDisabledPermanently(numberShowPermissionDialog)
}
} ?: kotlin.run {
listener.onNeedPermission()
}
} else {
// Is FirstTime
listener.onNeedPermission()
}
// Save history permission
sharedPreference.edit().putInt(permission, numberShowPermissionDialog + 1).apply()
} else {
listener.onPermissionGranted()
}
}
}
以这种方式使用
PermissionUtil().checkPermission(this, Manifest.permission.ACCESS_FINE_LOCATION,
object : PermissionListener {
override fun onNeedPermission() {
log("---------------------->onNeedPermission")
// ActivityCompat.requestPermissions(this@SplashActivity,
// Array(1) { Manifest.permission.ACCESS_FINE_LOCATION },
// 118)
}
override fun onPermissionPreviouslyDenied(numberDenyPermission: Int) {
log("---------------------->onPermissionPreviouslyDenied")
}
override fun onPermissionDisabledPermanently(numberDenyPermission: Int) {
log("---------------------->onPermissionDisabled")
}
override fun onPermissionGranted() {
log("---------------------->onPermissionGranted")
}
})
在activity或fragmnet中覆盖onRequestPermissionsResult
override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
if (requestCode == 118) {
if (permissions[0] == Manifest.permission.ACCESS_FINE_LOCATION && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
getLastLocationInMap()
}
}
}
扩展上面mVck的答案，下面的逻辑确定是否“Never ask again”已经为给定的权限请求进行了检查:
bool bStorage = grantResults[0] == Permission.Granted;
bool bNeverAskForStorage =
!bStorage && (
_bStorageRationaleBefore == true && _bStorageRationaleAfter == false ||
_bStorageRationaleBefore == false && _bStorageRationaleAfter == false
);
摘自下面(完整的例子见这个答案)
private bool _bStorageRationaleBefore;
private bool _bStorageRationaleAfter;
private const int ANDROID_PERMISSION_REQUEST_CODE__SDCARD = 2;
//private const int ANDROID_PERMISSION_REQUEST_CODE__CAMERA = 1;
private const int ANDROID_PERMISSION_REQUEST_CODE__NONE = 0;
public override void OnRequestPermissionsResult(int requestCode, string[] permissions, [GeneratedEnum] Permission[] grantResults)
{
base.OnRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode)
{
case ANDROID_PERMISSION_REQUEST_CODE__SDCARD:
_bStorageRationaleAfter = ShouldShowRequestPermissionRationale(Android.Manifest.Permission.WriteExternalStorage);
bool bStorage = grantResults[0] == Permission.Granted;
bool bNeverAskForStorage =
!bStorage && (
_bStorageRationaleBefore == true && _bStorageRationaleAfter == false ||
_bStorageRationaleBefore == false && _bStorageRationaleAfter == false
);
break;
}
}
private List<string> GetRequiredPermissions(out int requestCode)
{
// Android v6 requires explicit permission granting from user at runtime for security reasons
requestCode = ANDROID_PERMISSION_REQUEST_CODE__NONE; // 0
List<string> requiredPermissions = new List<string>();
_bStorageRationaleBefore = ShouldShowRequestPermissionRationale(Android.Manifest.Permission.WriteExternalStorage);
Permission writeExternalStoragePerm = ApplicationContext.CheckSelfPermission(Android.Manifest.Permission.WriteExternalStorage);
//if(extStoragePerm == Permission.Denied)
if (writeExternalStoragePerm != Permission.Granted)
{
requestCode |= ANDROID_PERMISSION_REQUEST_CODE__SDCARD;
requiredPermissions.Add(Android.Manifest.Permission.WriteExternalStorage);
}
return requiredPermissions;
}
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
// Android v6 requires explicit permission granting from user at runtime for security reasons
int requestCode;
List<string> requiredPermissions = GetRequiredPermissions(out requestCode);
if (requiredPermissions != null && requiredPermissions.Count > 0)
{
if (requestCode >= ANDROID_PERMISSION_REQUEST_CODE__SDCARD)
{
_savedInstanceState = savedInstanceState;
RequestPermissions(requiredPermissions.ToArray(), requestCode);
return;
}
}
}
OnCreate2(savedInstanceState);
}
您可以使用if (ActivityCompat。shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)方法来检测never ask是否被检查。
更多参考:检查这个
检查是否使用了多个权限:
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)
|| ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.WRITE_EXTERNAL_STORAGE)
|| ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.ACCESS_FINE_LOCATION)
|| ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.RECORD_AUDIO)) {
showDialogOK("Service Permissions are required for this app",
new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
switch (which) {
case DialogInterface.BUTTON_POSITIVE:
checkAndRequestPermissions();
break;
case DialogInterface.BUTTON_NEGATIVE:
// proceed with logic by disabling the related features or quit the app.
finish();
break;
}
}
});
}
//permission is denied (and never ask again is checked)
//shouldShowRequestPermissionRationale will return false
else {
explain("You need to give some mandatory permissions to continue. Do you want to go to app settings?");
// //proceed with logic by disabling the related features or quit the app.
}
解释()方法
private void explain(String msg){
final android.support.v7.app.AlertDialog.Builder dialog = new android.support.v7.app.AlertDialog.Builder(this);
dialog.setMessage(msg)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
// permissionsclass.requestPermission(type,code);
startActivity(new Intent(android.provider.Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:com.exampledemo.parsaniahardik.marshmallowpermission")));
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
finish();
}
});
dialog.show();
}
上面的代码还将显示对话框，这将重定向到用户的应用程序设置屏幕，在那里他可以给予权限，如果选中了“永不再问”按钮。
相反，你会收到回调onRequestPermissionsResult()作为PERMISSION_DENIED当你再次请求权限时，而落在shouldShowRequestPermissionRationale()的错误条件下
来自Android文档:
When the system asks the user to grant a permission, the user has the option of telling the system not to ask for that permission again. In that case, any time an app uses requestPermissions() to ask for that permission again, the system immediately denies the request. The system calls your onRequestPermissionsResult() callback method and passes PERMISSION_DENIED, the same way it would if the user had explicitly rejected your request again. This means that when you call requestPermissions(), you cannot assume that any direct interaction with the user has taken place.
我发现这个问题的方法对我来说有点新鲜。我必须保留一个参考，如果用户曾经选择了一个决定。通过这种方式，如果权限没有被授予，我可以告诉用户是第一次在那里，并且应该提示看到权限弹出，或者用户暂时或永久地拒绝它。
psudocode:
if( granted ) {
// you are set
} else if( requiresRationale() ) {
// in the ui let the user know he has to tap and launch permission
button.onSetClickListener { requestPermission() }
} else if( sharedPreferences.getBoolean("permission", false) ) {
// so user has already decided to deny permission, then it is permanent
launchAppSettings()
} else {
// user's first encounter, request permission
requestPermission()
}
演示文件以GIF格式附在自述文件中。 https://github.com/juanmendez/android-sdk-updates/tree/api/android-permissions/single
