How to invoke native camera in Delphi Android application?

  

I’m using Delphi 10.3 Community Edition to write a simple Android app and trying to invoke native device camera, but getting an error instead.

I’m following the official Delphi guide:

On the Form Designer, select the button (for taking a photo).
In the Object Inspector, select the drop-down list for the Action property.
Select New Standard Action | Media Library | TTakePhotoFromCameraAction:

On the Events tab, expand the Action node, and then double-click the OnDidFinishTaking event.

Add the following code to the OnDidFinishTaking event handler:

procedure TForm1.TakePhotoFromCameraAction1DidFinishTaking(Image: TBitmap);
begin
Image1.Bitmap.Assign(Image);
end;

This code assigns a picture taken from the mobile device camera to the Bitmap property of the TImage component.

I have verified that Project | Options | Uses Permissions – Camera setting is set to true. I’m requesting required permission on the app start as well. There’s no difference between running in Debug or Release.

However there is a problem. When clicking the button I get the following error message:

java.lang.NullPointerException: Attempt to invoke virtual method ‘android.content.res.XmlResourceParser android.content.pm.PackageItemInfo.loadXmlMetaData(android.content.pm.PackageManager, java.lang.String)’ on a null object reference.

Here’s the code I’ve written for the simplest test app:

unit Unit1;
interface
uses
System.SysUtils, System.Types, System.UITypes, System.Classes, System.Variants,
FMX.Types, FMX.Controls, FMX.Forms, FMX.Graphics, FMX.Dialogs, System.Permissions,
FMX.StdCtrls, FMX.MediaLibrary, FMX.Platform, System.Messaging, FMX.Objects,
System.Actions, FMX.ActnList, FMX.StdActns, FMX.MediaLibrary.Actions,
FMX.Controls.Presentation;

type
TForm1 = class(TForm)
Button1: TButton;
ActionList1: TActionList;
TakePhotoFromCameraAction1: TTakePhotoFromCameraAction;
procedure FormCreate(Sender: TObject);
private
procedure PermissionRequestResult(Sender: TObject; const APermissions: TArray<string>; const AGrantResults: TArray<TPermissionStatus>);
procedure DisplayRationale(Sender: TObject; const APermissions: TArray<string>; const APostRationaleProc: TProc);
end;

var
Form1: TForm1;

implementation
uses
{$IFDEF ANDROID}
Androidapi.Helpers,
Androidapi.JNI.JavaTypes,
Androidapi.JNI.Os,
{$ENDIF}
FMX.DialogService;

{$R *.fmx}

procedure TForm1.PermissionRequestResult(Sender: TObject; const APermissions: TArray<string>; const AGrantResults: TArray<TPermissionStatus>);
begin
// 3 permission involved
if (Length(AGrantResults) = 3)
and (AGrantResults[0] = TPermissionStatus.Granted)
and (AGrantResults[1] = TPermissionStatus.Granted)
and (AGrantResults[2] = TPermissionStatus.Granted) then
else
ShowMessage(‘Required permission has not been granted’) ;
end;

procedure TForm1.DisplayRationale(Sender: TObject; const APermissions: TArray<string>; const APostRationaleProc: TProc);
begin
TDialogService.ShowMessage(‘Need to access the camera’,
procedure(const AResult: TModalResult)
begin
APostRationaleProc;
end);
end;

procedure TForm1.FormCreate(Sender: TObject);
var
permCam, permRead, permWrite: string;
begin
// Request permissions
permCam := JStringToString(TJManifest_permission.JavaClass.CAMERA);
permRead := JStringToString(TJManifest_permission.JavaClass.READ_EXTERNAL_STORAGE);
permWrite := JStringToString(TJManifest_permission.JavaClass.WRITE_EXTERNAL_STORAGE);
PermissionsService.RequestPermissions([permCam, permRead, permWrite], PermissionRequestResult, DisplayRationale);
end;

end.

How to make the native camera TTakePhotoFromCameraAction to work?

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