我正在翻阅关于Android m中的新权限模型的官方文档。它讨论了shouldShowRequestPermissionRationale()函数，如果应用程序之前请求了此权限，并且用户拒绝了请求，该函数将返回true。如果用户在过去拒绝了权限请求并选择Don't ask again选项，则此方法返回false。
但是我们如何区分以下两种情况呢?
案例1:应用程序没有权限，之前也没有向用户请求过权限。在这种情况下，shouldShowRequestPermissionRationale()将返回false，因为这是我们第一次请求用户。
情况2:用户拒绝了权限并选择了“不要再问了”，在这种情况下shouldShowRequestPermissionRationale()将返回false。
我想把用户发送到案例2中的应用设置页面。我怎么微分这两种情况呢?
当前回答
正确使用shouldShowRequestPermissionRationale是on onRequestPermissionsResult。
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.LinearLayoutCompat
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity"
android:gravity="center">
<androidx.appcompat.widget.AppCompatButton
android:id="@+id/btn_camera"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Camera"
android:textAllCaps="false"
android:background="@color/purple_200"
android:layout_marginTop="20dp"
>
</androidx.appcompat.widget.AppCompatButton>
<androidx.appcompat.widget.AppCompatButton
android:id="@+id/btn_storage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Storage"
android:textAllCaps="false"
android:background="@color/purple_200"
android:layout_marginTop="30dp"
>
</androidx.appcompat.widget.AppCompatButton>
</androidx.appcompat.widget.LinearLayoutCompat>
enter code here
MainActivity.kt
package com.example.myapplication
import android.Manifest
import android.content.pm.PackageManager
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.widget.Button
import android.widget.Toast
import androidx.appcompat.app.AlertDialog
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
class MainActivity : AppCompatActivity() {
private val TAG = "MainActivity"
lateinit var btnCamera: Button
private val cameraRequestCode = 100
lateinit var btnStorage: Button
private val storageRequestCode = 200
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
btnCamera = findViewById(R.id.btn_camera)
btnStorage = findViewById(R.id.btn_storage)
btnCamera.setOnClickListener {
checkPermission(android.Manifest.permission.CAMERA, cameraRequestCode)
}
btnStorage.setOnClickListener {
checkPermission(android.Manifest.permission.READ_EXTERNAL_STORAGE, storageRequestCode)
}
}
private fun checkPermission(permissionName: String, requestCode: Int) {
/**
* if the permission is given means it will give the permissionNumber = 0
* if the permission is not given means it will give the permissionNumber =-1
* It s same as we are checking for PackageManager.PERMISSION_DENIED =-1 & PackageManager.GRANTED=0
*/
val permissionNumber: Int =
ContextCompat.checkSelfPermission(this@MainActivity, permissionName)
if (permissionNumber == PackageManager.PERMISSION_GRANTED) {
} else if (permissionNumber == PackageManager.PERMISSION_DENIED) {
askpermission(permissionName, requestCode, permissionNumber)
}
}
private fun askpermission(permissionName: String, permissionCode: Int, permissionNumner: Int) {
ActivityCompat.requestPermissions(
this@MainActivity,
arrayOf(permissionName),
permissionCode
)
}
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<out String>,
grantResults: IntArray
) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults)
if (requestCode == cameraRequestCode) {
if (permissions.size > 0) {
if (permissions[0].toString().equals(Manifest.permission.CAMERA, ignoreCase = true)) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(applicationContext,"Permission Granted",Toast.LENGTH_SHORT).show()
}else{
if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
var permissionDeniedStatus= checkDeniedPermissionStatus(permissions[0]);
if(permissionDeniedStatus){
/**
* Permission Denied
*/
Toast.makeText(applicationContext,"Permission Denied",Toast.LENGTH_SHORT).show()
}else{
/**
* Permission Denied and Selected Don t ask again.
*/
showDialog("Permission Denied","Permission Denied Permanently\nOpen Setting to allow")
}
}
}
}
}
}else if (requestCode == storageRequestCode) {
if(permissions[0].toString().equals(Manifest.permission.READ_EXTERNAL_STORAGE, ignoreCase = true)){
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(applicationContext,"Permission Granted",Toast.LENGTH_SHORT).show()
}
}else{
if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
var permissionDeniedStatus= checkDeniedPermissionStatus(permissions[0]);
if(permissionDeniedStatus){
/**
* Permission Denied
*/
Toast.makeText(applicationContext,"Permission Denied",Toast.LENGTH_SHORT).show()
}else{
/**
* Permission Denied and Selected Don t ask again.
*/
showDialog("Permission Denied","Permission Denied Permanently\nOpen Setting to allow")
}
}
}
}
}
}
private fun checkDeniedPermissionStatus(permissionName: String) :Boolean{
val permissionDeniedStatus: Boolean = ActivityCompat.shouldShowRequestPermissionRationale(this@MainActivity, permissionName)
return permissionDeniedStatus
}
private fun showDialog(title: String, message: String) {
val builder = AlertDialog.Builder(this)
builder.setTitle(title)
builder.setMessage(message)
builder.setPositiveButton(android.R.string.yes) { dialog, which ->
}
builder.setNegativeButton(android.R.string.no) { dialog, which ->
}
builder.show()
}
}
其他回答
public void requestPermission(View view){
if(ContextCompat.checkSelfPermission(this,Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED){
if(ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,Manifest.permission.ACCESS_FINE_LOCATION)){
//The Alert Dialog before asking for the second time to help the user understand why he needs to give permission.
AlertDialog alert = new AlertDialog.Builder(this).setMessage("Without the permissions you cannot run the application")
.setCancelable(false)
.setPositiveButton("Okay, I understand", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_FINE_LOCATION);
}
}).setNegativeButton("No, Exit the App", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
System.exit(2);
}
}).create();
alert.setTitle("ALERTY");
alert.show();
//End of the alert Dialog
}
else{
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_FINE_LOCATION);
}
}
else {
textView.setText("Permission Is Already Granted");
}
}
/*
The shouldShowRequestPermissionRationale() function returns true if the app has requested this permission
previously and the user denied the request.If the user turned down the permission request in the past and chose
the Don't ask again option, this method returns false.
*/
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
if(requestCode == REQUEST_FINE_LOCATION) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
textView.setText("Hooray! on Request Permissions Granted");
}
else{
//Since the user has chosen the don't ask again option,
if(!ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.ACCESS_FINE_LOCATION)){
//Alert Dialog that will take user to settings where he can manually give the permissions
AlertDialog alert = new AlertDialog.Builder(this).setMessage("You have permanently disabled the permission ")
.setPositiveButton("Go to Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
openSettings();
}
}).setNegativeButton("Don't Go",null).setCancelable(false).create();
alert.setTitle("Give permission manually");
alert.show();
// End of the Alert Dialog
}
else{
textView.setText("Permission has been denied the 1st time");
}
}
}
}
这是openSettings方法。
public void openSettings(){
Intent intent = new Intent();
Uri uri = Uri.fromParts("package",this.getPackageName(),null);
intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS).setData(uri);
startActivity(intent);
}
“M Preview 1”后，如果第一次弹出对话框，则没有“Never ask again”复选框。
如果用户拒绝权限请求，第二次请求权限时，权限对话框中会出现“Never ask again”复选框。
所以逻辑应该是这样的:
Request permission: if (ContextCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { ActivityCompat.requestPermissions(context, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, REQUEST_CODE); } else { //Do the stuff that requires permission... } Check if the permission was denied or granted in onRequestPermissionsResult. If the permission was denied previously, this time there will be a Never ask again checkbox in the permission dialog. Call shouldShowRequestPermissionRationale to see if the user checked Never ask again. shouldShowRequestPermissionRationale method returns false only if the user selected Never ask again or device policy prohibits the app from having that permission: if (grantResults.length > 0){ if(grantResults[0] == PackageManager.PERMISSION_GRANTED) { //Do the stuff that requires permission... }else if (grantResults[0] == PackageManager.PERMISSION_DENIED){ // Should we show an explanation? if (ActivityCompat.shouldShowRequestPermissionRationale(context, Manifest.permission.WRITE_EXTERNAL_STORAGE)) { //Show permission explanation dialog... }else{ //Never ask again selected, or device policy prohibits the app from having that permission. //So, disable that feature, or fall back to another situation... } } }
因此，如果用户勾选了“永不再问”，您将不必跟踪。
可能对某人有用:——
我注意到的是，如果我们在onRequestPermissionsResult()回调方法中检查shouldshowrequestpermissionration理()标志，它只显示两种状态。
状态1:-返回true:——任何时候用户单击Deny permissions(包括第一次)。
状态2:-返回false:-如果用户选择“永不再问”。
链接到详细的工作示例。
我们可以这样做吗?
@Retention(RetentionPolicy.SOURCE)
@IntDef({GRANTED, DENIED, NEVER})
public @interface PermissionStatus {
}
public static final int GRANTED = 0;
public static final int DENIED = 1;
public static final int NEVER = 2;
@PermissionStatus
public static int getPermissionStatus(Activity activity, String permission) {
if (ActivityCompat.shouldShowRequestPermissionRationale(activity, permission)) {
return DENIED;
} else {
if (ActivityCompat.checkSelfPermission(activity, permission) == PackageManager.PERMISSION_GRANTED) {
return GRANTED;
} else {
return NEVER;
}
}
}
正确使用shouldShowRequestPermissionRationale是on onRequestPermissionsResult。
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.LinearLayoutCompat
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity"
android:gravity="center">
<androidx.appcompat.widget.AppCompatButton
android:id="@+id/btn_camera"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Camera"
android:textAllCaps="false"
android:background="@color/purple_200"
android:layout_marginTop="20dp"
>
</androidx.appcompat.widget.AppCompatButton>
<androidx.appcompat.widget.AppCompatButton
android:id="@+id/btn_storage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Storage"
android:textAllCaps="false"
android:background="@color/purple_200"
android:layout_marginTop="30dp"
>
</androidx.appcompat.widget.AppCompatButton>
</androidx.appcompat.widget.LinearLayoutCompat>
enter code here
MainActivity.kt
package com.example.myapplication
import android.Manifest
import android.content.pm.PackageManager
import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import android.util.Log
import android.widget.Button
import android.widget.Toast
import androidx.appcompat.app.AlertDialog
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
class MainActivity : AppCompatActivity() {
private val TAG = "MainActivity"
lateinit var btnCamera: Button
private val cameraRequestCode = 100
lateinit var btnStorage: Button
private val storageRequestCode = 200
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
btnCamera = findViewById(R.id.btn_camera)
btnStorage = findViewById(R.id.btn_storage)
btnCamera.setOnClickListener {
checkPermission(android.Manifest.permission.CAMERA, cameraRequestCode)
}
btnStorage.setOnClickListener {
checkPermission(android.Manifest.permission.READ_EXTERNAL_STORAGE, storageRequestCode)
}
}
private fun checkPermission(permissionName: String, requestCode: Int) {
/**
* if the permission is given means it will give the permissionNumber = 0
* if the permission is not given means it will give the permissionNumber =-1
* It s same as we are checking for PackageManager.PERMISSION_DENIED =-1 & PackageManager.GRANTED=0
*/
val permissionNumber: Int =
ContextCompat.checkSelfPermission(this@MainActivity, permissionName)
if (permissionNumber == PackageManager.PERMISSION_GRANTED) {
} else if (permissionNumber == PackageManager.PERMISSION_DENIED) {
askpermission(permissionName, requestCode, permissionNumber)
}
}
private fun askpermission(permissionName: String, permissionCode: Int, permissionNumner: Int) {
ActivityCompat.requestPermissions(
this@MainActivity,
arrayOf(permissionName),
permissionCode
)
}
override fun onRequestPermissionsResult(
requestCode: Int,
permissions: Array<out String>,
grantResults: IntArray
) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults)
if (requestCode == cameraRequestCode) {
if (permissions.size > 0) {
if (permissions[0].toString().equals(Manifest.permission.CAMERA, ignoreCase = true)) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(applicationContext,"Permission Granted",Toast.LENGTH_SHORT).show()
}else{
if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
var permissionDeniedStatus= checkDeniedPermissionStatus(permissions[0]);
if(permissionDeniedStatus){
/**
* Permission Denied
*/
Toast.makeText(applicationContext,"Permission Denied",Toast.LENGTH_SHORT).show()
}else{
/**
* Permission Denied and Selected Don t ask again.
*/
showDialog("Permission Denied","Permission Denied Permanently\nOpen Setting to allow")
}
}
}
}
}
}else if (requestCode == storageRequestCode) {
if(permissions[0].toString().equals(Manifest.permission.READ_EXTERNAL_STORAGE, ignoreCase = true)){
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(applicationContext,"Permission Granted",Toast.LENGTH_SHORT).show()
}
}else{
if (grantResults[0] == PackageManager.PERMISSION_DENIED) {
var permissionDeniedStatus= checkDeniedPermissionStatus(permissions[0]);
if(permissionDeniedStatus){
/**
* Permission Denied
*/
Toast.makeText(applicationContext,"Permission Denied",Toast.LENGTH_SHORT).show()
}else{
/**
* Permission Denied and Selected Don t ask again.
*/
showDialog("Permission Denied","Permission Denied Permanently\nOpen Setting to allow")
}
}
}
}
}
}
private fun checkDeniedPermissionStatus(permissionName: String) :Boolean{
val permissionDeniedStatus: Boolean = ActivityCompat.shouldShowRequestPermissionRationale(this@MainActivity, permissionName)
return permissionDeniedStatus
}
private fun showDialog(title: String, message: String) {
val builder = AlertDialog.Builder(this)
builder.setTitle(title)
builder.setMessage(message)
builder.setPositiveButton(android.R.string.yes) { dialog, which ->
}
builder.setNegativeButton(android.R.string.no) { dialog, which ->
}
builder.show()
}
}
