请求清单文件中声明的所有权限

Question

我正在使用 xamarin 构建 android 应用程序问题我对 c# 不太熟悉...所以我试图让我的应用程序请求我已经在清单文件中一次声明的所有权限 我试过这个，但它只请求相机权限

if (ContextCompat.CheckSelfPermission(this, Manifest.Permission.Camera) ==(int)Permission.Granted) 
{
// We have permission, go ahead and use the camera.
} 
else 
{
// Camera permission is not granted. If necessary display rationale & request.
} 
    

如何让这段代码请求所有声明的权限？

Answer 1

ActivityCompat.requestPermissions(this, new String[] {Manifest.permission.Camera}, 1);

您可以在数组中请求更多您想要的权限。另外，请注意 1 是请求代码。

有关更多信息，请参阅documentation。

Answer 2

对此，可以参考官方文档：Permissions In Xamarin.Android。

还有一个关于此的示例，您可以在这里查看：https://github.com/xamarin/monodroid-samples/tree/master/android-m/RuntimePermissions。

如果要定义两个以上的权限，可以参考下面的代码sn-ps（这里我们要在我们的设备中读写cotacts）：

    /**
    * Id to identify a contacts permission request.
    */
    static readonly int REQUEST_CONTACTS = 1;

    /**
    * Permissions required to read and write contacts. Used by the ContactsFragment.
    */
    static string[] PERMISSIONS_CONTACT = {
        Manifest.Permission.ReadContacts,
        Manifest.Permission.WriteContacts
    };

    public void ShowContacts (View v)
    {
        Log.Info (TAG, "Show contacts button pressed. Checking permissions.");

        // Verify that all required contact permissions have been granted.
        if (ActivityCompat.CheckSelfPermission (this, Manifest.Permission.ReadContacts) != (int)Permission.Granted
            || ActivityCompat.CheckSelfPermission (this, Manifest.Permission.WriteContacts) != (int)Permission.Granted) {
            // Contacts permissions have not been granted.
            Log.Info (TAG, "Contact permissions has NOT been granted. Requesting permissions.");
            RequestContactsPermissions ();
        } else {
            // Contact permissions have been granted. Show the contacts fragment.
            Log.Info (TAG, "Contact permissions have already been granted. Displaying contact details.");
            ShowContactDetails ();
        }
    }

方法：RequestContactsPermissions

    void RequestContactsPermissions ()
    {
        if (ActivityCompat.ShouldShowRequestPermissionRationale (this, Manifest.Permission.ReadContacts)
            || ActivityCompat.ShouldShowRequestPermissionRationale (this, Manifest.Permission.WriteContacts)) {

            // Provide an additional rationale to the user if the permission was not granted
            // and the user would benefit from additional context for the use of the permission.
            // For example, if the request has been denied previously.
            Log.Info (TAG, "Displaying contacts permission rationale to provide additional context.");

            // Display a SnackBar with an explanation and a button to trigger the request.
            Snackbar.Make (layout, Resource.String.permission_contacts_rationale,
                Snackbar.LengthIndefinite).SetAction (Resource.String.ok, new Action<View> (delegate(View obj) {
                    ActivityCompat.RequestPermissions (this, PERMISSIONS_CONTACT, REQUEST_CONTACTS);
                })).Show ();
        } else {
            // Contact permissions have not been granted yet. Request them directly.
            ActivityCompat.RequestPermissions (this, PERMISSIONS_CONTACT, REQUEST_CONTACTS);
        }
    }

方法OnRequestPermissionsResult

    public override void OnRequestPermissionsResult (int requestCode, string[] permissions, Permission[] grantResults)
    {
         if (requestCode == REQUEST_CONTACTS) {
            Log.Info (TAG, "Received response for contact permissions request.");

            // We have requested multiple permissions for contacts, so all of them need to be
            // checked.
            if (PermissionUtil.VerifyPermissions (grantResults)) {
                // All required permissions have been granted, display contacts fragment.
                Snackbar.Make (layout, Resource.String.permission_available_contacts, Snackbar.LengthShort).Show ();
            } else {
                Log.Info (TAG, "Contacts permissions were NOT granted.");
                Snackbar.Make (layout, Resource.String.permissions_not_granted, Snackbar.LengthShort).Show ();
            }

        } else {
            base.OnRequestPermissionsResult (requestCode, permissions, grantResults);
        }
    }

更多详细信息，您可以查看示例：https://github.com/xamarin/monodroid-samples/tree/master/android-m/RuntimePermissions。