In Kotlin, you can request permission from the user to execute certain actions, such as accessing the camera or location services. To get permission results, you can use the requestPermissions() method. This method takes in an array of permissions that you want to request, as well as a unique permission code. Once the user accepts or denies the permission request, the onRequestPermissionsResult() method will be called, where you can handle the result of the permission request. You can check if the permission was granted by checking the grantResults array in the onRequestPermissionsResult() method. If the permission is granted, you can proceed with the desired action. If the permission is denied, you can handle it accordingly, such as showing a message to the user or requesting the permission again.
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How to get permission result in kotlin for storage access?
To get permission result in Kotlin for storage access, you need to first request the necessary permission from the user using the following code:
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val storagePermission = Manifest.permission.READ_EXTERNAL_STORAGE
if (ContextCompat.checkSelfPermission(this, storagePermission)
!= PackageManager.PERMISSION_GRANTED) {
// Permission is not granted
if (ActivityCompat.shouldShowRequestPermissionRationale(this, storagePermission)) {
// Explain why you need this permission
} else {
// Request the permission
ActivityCompat.requestPermissions(this, arrayOf(storagePermission), requestCode)
}
}
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After requesting the permission, you need to override the onRequestPermissionsResult method in your activity to handle the permission result:
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override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray) {
when (requestCode) {
requestCode -> {
if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Permission is granted
} else {
// Permission is denied
}
return
}
}
}
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This code snippet demonstrates how to request storage permission in Kotlin and handle the result accordingly.
What is the best practice for handling permission result in kotlin?
The best practice for handling permission results in Kotlin is to use the PermissionDispatcher library. This library makes it easy to request, check, and handle permissions in your Android app.
To handle permission results using PermissionDispatcher, follow these steps:
- Add the PermissionDispatcher library to your project by adding the following dependency to your app's build.gradle file:
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implementation 'com.github.hotchemi:permissionsdispatcher:4.7.0'
kapt 'com.github.hotchemi:permissionsdispatcher-processor:4.7.0'
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- Create a custom annotation interface in your Kotlin file to define the permissions you want to request. For example:
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@RuntimePermissions
interface MyActivity {
fun onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray)
}
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- Use the @NeedsPermission annotation to annotate the method where you want to request permissions. For example:
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@NeedsPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE)
fun showCamera() {
// Code to handle permission granted
}
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- Use the @OnShowRationale annotation to annotate a method that explains why the permission is needed. For example:
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@OnShowRationale(Manifest.permission.WRITE_EXTERNAL_STORAGE)
fun showRationaleForStorage(request: PermissionRequest) {
// Show rationale dialog explaining why the permission is needed
request.proceed()
}
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- Use the @OnPermissionDenied annotation to annotate a method that is called when the permission is denied. For example:
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@OnPermissionDenied(Manifest.permission.WRITE_EXTERNAL_STORAGE)
fun onStorageDenied() {
// Handle permission denied
}
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- Use the @OnNeverAskAgain annotation to annotate a method that is called if the permission is denied and the "Never ask again" checkbox is checked. For example:
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@OnNeverAskAgain(Manifest.permission.WRITE_EXTERNAL_STORAGE)
fun onStorageNeverAskAgain() {
// Handle "Never ask again" scenario
}
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- Finally, use the PermissionsDispatcher class to request permissions in your activity or fragment. For example:
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PermissionsDispatcher.showCameraWithPermissionCheck(this)
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By following these best practices and using the PermissionDispatcher library, you can easily handle permission results in your Kotlin app in a clean and organized way.
How to request permissions at runtime in kotlin?
In Kotlin, you can request permissions at runtime by using the ActivityCompat.requestPermissions() function. Here is an example of how you can request the CAMERA permission at runtime:
- Check if the permission is granted:
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if (ContextCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
!= PackageManager.PERMISSION_GRANTED) {
// Permission is not granted
// Request the permission
ActivityCompat.requestPermissions(this,
arrayOf(Manifest.permission.CAMERA),
REQUEST_CAMERA_PERMISSION)
} else {
// Permission is already granted
// Do your work here
}
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- Handle the result of the permission request:
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override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
when (requestCode) {
REQUEST_CAMERA_PERMISSION -> {
if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// Permission granted, do your work here
} else {
// Permission denied, show an error message or request again
}
}
}
}
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Make sure to replace REQUEST_CAMERA_PERMISSION with a unique identifier for the permission request. Also, don't forget to add the necessary permissions to your AndroidManifest.xml file.
