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)。

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.

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).
        }
    }
}

请不要为这个解决办法向我扔石头。

这是可行的，但有点“俗气”。

当调用requestPermissions时，注册当前时间。

        mAskedPermissionTime = System.currentTimeMillis();

然后在onRequestPermissionsResult中

如果结果不允许，请再次检查时间。

 if (System.currentTimeMillis() - mAskedPermissionTime < 100)

由于用户不可能那么快地点击拒绝按钮，我们知道他选择了“永不再问”，因为回调是即时的。

使用风险自负。

在阅读了一些答案后，我发现了许多冗长而令人困惑的答案 我的结论是

if (!ActivityCompat.shouldShowRequestPermissionRationale(this,Manifest.permission.READ_EXTERNAL_STORAGE))
                Toast.makeText(this, "permanently denied", Toast.LENGTH_SHORT).show();

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.
        }

    }
}