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
一个有用的函数来确定任意权限是否被阻止请求(在Kotlin中):
private fun isPermissionBlockedFromAsking(activity: Activity, permission: String): Boolean {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
return ContextCompat.checkSelfPermission(activity, permission) != PackageManager.PERMISSION_GRANTED
&& !activity.shouldShowRequestPermissionRationale(permission)
&& PreferenceManager.getDefaultSharedPreferences(activity).getBoolean(permission, false)
}
return false
}
当你第一次请求一个权限时，需要设置一个共享首选项布尔值为true，其中包含你想要的权限名称(例如android.Manifest.permission.READ_PHONE_STATE)。
解释:
Build.VERSION。SDK_INT >= Build.VERSION_CODES。因为有些代码只能在API级别23+上运行。
ContextCompat。checkSelfPermission(activity, permission) != PackageManager。permission_granting检查我们还没有权限。
activity.shouldShowRequestPermissionRationale(permission)来检查用户是否再次拒绝了应用程序的请求。由于这个函数的特性，还需要下面这行代码。
PreferenceManager.getDefaultSharedPreferences(活动)。getBoolean(permission, false)用于区分“Never asked”和“Never ask again”状态(以及在第一次权限请求时将值设置为true)，因为前一行不会返回此信息。
其他回答
你可以在onRequestPermissionsResult()中检查shouldShowRequestPermissionRationale()。
https://youtu.be/C8lUdPVSzDk?t=2m23s
在onRequestPermissionsResult()中检查权限是否被授予。如果不是，检查shouldShowRequestPermissionRationale()。
如果此方法返回true，则说明为什么需要此特定权限。然后根据用户的选择再次请求permissions()。 如果它返回false，则显示一个错误消息，权限未授予，应用程序不能继续前进或特定功能被禁用。
下面是示例代码。
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode) {
case STORAGE_PERMISSION_REQUEST:
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// permission was granted :)
downloadFile();
} else {
// permission was not granted
if (getActivity() == null) {
return;
}
if (ActivityCompat.shouldShowRequestPermissionRationale(getActivity(), Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
showStoragePermissionRationale();
} else {
Snackbar snackbar = Snackbar.make(getView(), getResources().getString(R.string.message_no_storage_permission_snackbar), Snackbar.LENGTH_LONG);
snackbar.setAction(getResources().getString(R.string.settings), new View.OnClickListener() {
@Override
public void onClick(View v) {
if (getActivity() == null) {
return;
}
Intent intent = new Intent();
intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
Uri uri = Uri.fromParts("package", getActivity().getPackageName(), null);
intent.setData(uri);
OrderDetailFragment.this.startActivity(intent);
}
});
snackbar.show();
}
}
break;
}
}
显然，谷歌maps对位置许可正是这样做的。
一个有用的函数来确定任意权限是否被阻止请求(在Kotlin中):
private fun isPermissionBlockedFromAsking(activity: Activity, permission: String): Boolean {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
return ContextCompat.checkSelfPermission(activity, permission) != PackageManager.PERMISSION_GRANTED
&& !activity.shouldShowRequestPermissionRationale(permission)
&& PreferenceManager.getDefaultSharedPreferences(activity).getBoolean(permission, false)
}
return false
}
当你第一次请求一个权限时，需要设置一个共享首选项布尔值为true，其中包含你想要的权限名称(例如android.Manifest.permission.READ_PHONE_STATE)。
解释:
Build.VERSION。SDK_INT >= Build.VERSION_CODES。因为有些代码只能在API级别23+上运行。
ContextCompat。checkSelfPermission(activity, permission) != PackageManager。permission_granting检查我们还没有权限。
activity.shouldShowRequestPermissionRationale(permission)来检查用户是否再次拒绝了应用程序的请求。由于这个函数的特性，还需要下面这行代码。
PreferenceManager.getDefaultSharedPreferences(活动)。getBoolean(permission, false)用于区分“Never asked”和“Never ask again”状态(以及在第一次权限请求时将值设置为true)，因为前一行不会返回此信息。
您可以通过检查权限原理是否显示在onRequestPermissionsResult()回调方法中来确定它。如果您发现任何权限集永远不会再次请求，您可以请求用户从设置中授予权限。
我的完整实现如下所示。它适用于单个或多个权限请求。使用以下或直接使用我的库。
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
if(permissions.length == 0){
return;
}
boolean allPermissionsGranted = true;
if(grantResults.length>0){
for(int grantResult: grantResults){
if(grantResult != PackageManager.PERMISSION_GRANTED){
allPermissionsGranted = false;
break;
}
}
}
if(!allPermissionsGranted){
boolean somePermissionsForeverDenied = false;
for(String permission: permissions){
if(ActivityCompat.shouldShowRequestPermissionRationale(this, permission)){
//denied
Log.e("denied", permission);
}else{
if(ActivityCompat.checkSelfPermission(this, permission) == PackageManager.PERMISSION_GRANTED){
//allowed
Log.e("allowed", permission);
} else{
//set to never ask again
Log.e("set to never ask again", permission);
somePermissionsForeverDenied = true;
}
}
}
if(somePermissionsForeverDenied){
final AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(this);
alertDialogBuilder.setTitle("Permissions Required")
.setMessage("You have forcefully denied some of the required permissions " +
"for this action. Please open settings, go to permissions and allow them.")
.setPositiveButton("Settings", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS,
Uri.fromParts("package", getPackageName(), null));
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
}
})
.setCancelable(false)
.create()
.show();
}
} else {
switch (requestCode) {
//act according to the request code used while requesting the permission(s).
}
}
}
对每一种许可情况的完整解释
/**
* Case 1: User doesn't have permission
* Case 2: User has permission
*
* Case 3: User has never seen the permission Dialog
* Case 4: User has denied permission once but he din't clicked on "Never Show again" check box
* Case 5: User denied the permission and also clicked on the "Never Show again" check box.
* Case 6: User has allowed the permission
*
*/
public void handlePermission() {
if (ContextCompat.checkSelfPermission(MainActivity.this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
// This is Case 1. Now we need to check further if permission was shown before or not
if (ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
// This is Case 4.
} else {
// This is Case 3. Request for permission here
}
} else {
// This is Case 2. You have permission now you can do anything related to it
}
}
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
if (grantResults[0] == PackageManager.PERMISSION_GRANTED) {
// This is Case 2 (Permission is now granted)
} else {
// This is Case 1 again as Permission is not granted by user
//Now further we check if used denied permanently or not
if (ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
// case 4 User has denied permission but not permanently
} else {
// case 5. Permission denied permanently.
// You can open Permission setting's page from here now.
}
}
}
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。
