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。
OnRequestPermissionResult-free和shouldshowrequestpermissionrationalfree方法:
public static void requestDangerousPermission(AppCompatActivity activity, String permission) {
if (hasPermission(activity, permission)) return;
requestPermission();
new Handler().postDelayed(() -> {
if (activity.getLifecycle().getCurrentState() == Lifecycle.State.RESUMED) {
Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
intent.setData(Uri.parse("package:" + context.getPackageName()));
context.startActivity(intent);
}
}, 250);
}
如果没有权限弹出,250ms后打开设备设置(如果选择了“Never ask again”,就是这种情况)。
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。
我有点晚了,我也遇到过类似的问题。解决此问题如下
假设您需要位置权限
请求权限启动器
private final ActivityResultLauncher<String> requestPermissionLauncher =
registerForActivityResult(
new RequestPermission(),
isGranted -> {
if (isGranted) {
// Permission is granted go ahead
} else {
shouldShowRequestPermissionRationale();
}
});
权限检查
private boolean hasPermissions() {
if (checkSelfPermission(requireActivity(), ACCESS_FINE_LOCATION) == PERMISSION_GRANTED) {
// Permission is granted go ahead
} else {
requestPermissionLauncher.launch(ACCESS_FINE_LOCATION);
}
}
检查是否需要显示权限理性/自定义对话来教育用户
private void shouldShowRequestPermissionRationale() {
if (!shouldShowRequestPermissionRationale(ACCESS_FINE_LOCATION)) {
// need to show permission rational custom dialog.
}
}
这里有一个很好的和简单的方法来检查当前的权限状态:
@Retention(RetentionPolicy.SOURCE)
@IntDef({GRANTED, DENIED, BLOCKED_OR_NEVER_ASKED })
public @interface PermissionStatus {}
public static final int GRANTED = 0;
public static final int DENIED = 1;
public static final int BLOCKED_OR_NEVER_ASKED = 2;
@PermissionStatus
public static int getPermissionStatus(Activity activity, String androidPermissionName) {
if(ContextCompat.checkSelfPermission(activity, androidPermissionName) != PackageManager.PERMISSION_GRANTED) {
if(!ActivityCompat.shouldShowRequestPermissionRationale(activity, androidPermissionName)){
return BLOCKED_OR_NEVER_ASKED;
}
return DENIED;
}
return GRANTED;
}
警告:在用户通过用户提示接受/拒绝权限之前,在第一个应用程序启动时返回BLOCKED_OR_NEVER_ASKED(在sdk 23+设备上)
更新:
Android支持库现在似乎也有一个非常类似的类Android .support.v4.content。PermissionChecker,包含checkSelfPermission(),返回:
public static final int PERMISSION_GRANTED = 0;
public static final int PERMISSION_DENIED = -1;
public static final int PERMISSION_DENIED_APP_OP = -2;
为了准确地回答这个问题,当用户按下“永不再问”时会发生什么?
重写的方法/函数
onRequestPermissionsResult(requestCode: Int, permissions: Array<out String>, grantResults: IntArray)
grantResult数组显示为空,你可以在这里做些什么?但不是最好的做法。
如何处理“永不再问”?
我正在使用Fragment,它需要READ_EXTERNAL_STORAGE权限。
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
when {
isReadPermissionsGranted() -> {
/**
* Permissions has been Granted
*/
getDirectories()
}
isPermissionDeniedBefore() -> {
/**
* User has denied before, explain why we need the permission and ask again
*/
updateUIForDeniedPermissions()
checkIfPermissionIsGrantedNow()
}
else -> {
/**
* Need to ask For Permissions, First Time
*/
checkIfPermissionIsGrantedNow()
/**
* If user selects, "Dont Ask Again" it will never ask again! so just update the UI for Denied Permissions
*/
updateUIForDeniedPermissions()
}
}
}
其他的函数是微不足道的。
// Is Read Write Permissions Granted
fun isReadWritePermissionGranted(context: Context): Boolean {
return (ContextCompat.checkSelfPermission(
context as Activity,
Manifest.permission.READ_EXTERNAL_STORAGE
) == PackageManager.PERMISSION_GRANTED) and
(ContextCompat.checkSelfPermission(
context,
Manifest.permission.WRITE_EXTERNAL_STORAGE
) == PackageManager.PERMISSION_GRANTED)
}
fun isReadPermissionDenied(context: Context) : Boolean {
return ActivityCompat.shouldShowRequestPermissionRationale(
context as Activity,
PermissionsUtils.READ_EXTERNAL_STORAGE_PERMISSIONS)
}