Develop Reference

Mute/stop video running in background (Delphi - Android App)

I have an application in Delphi that plays video. When I open another application, but blank the screen, I hear the Video sound all the time.
How can I detect that the screen has been blanked, or there has been a switch to another application ?

I found a solution.
uses FMX.Platform;
procedure TMyForm.FormCreate(Sender: TObject);
var
AppEventSvc:IFMXApplicationEventService;
begin
if TPlatformServices.Current.SupportsPlatformService(IFMXApplicationEventService,IInterface(AppEventSvc)) then
begin
AppEventSvc.SetApplicationEventHandler(AppEvent);
end;
end;
function TMyForm.AppEvent(AAppEvent:TApplicationEvent;AContext:TObject):Boolean;
begin
if AAppEvent=TApplicationEvent.WillTerminate then
begin
// Do soomething
end;
Result:=True;
end;

Firemonkey: How to detect when the OS (Android/iOS) is going to shutdown

I am dealing with the following issue with Firemonkey (Delphi 10.4): When the Android OS will shut down and my app is still running, it does not trigger the OnCloseQuery, OnClose, and nor the OnDestroy events. Is there a way to detect or intercept the OS shutdown event? The same issue is presented when I kill the app with the square button (that is when I show the recently opened apps with the square button and I close the app that way).
Thank you in advance.

I finally found a solution from a TMS customer (Ken Randall "Randall_Ken" Active Customer.)
uses FMX.Platform;
procedure TMyForm.FormCreate(Sender: TObject);
var
AppEventSvc: IFMXApplicationEventService;
begin
if TPlatformServices.Current.SupportsPlatformService
(IFMXApplicationEventService, IInterface(AppEventSvc)) then
begin
AppEventSvc.SetApplicationEventHandler(AppEvent);
end;
end;
function TMyForm.AppEvent(AAppEvent: TApplicationEvent;
AContext: TObject): Boolean;
begin
if AAppEvent = TApplicationEvent.WillTerminate then
begin
// Do soomething
end;
Result := true;
end;

Delphi/Firemonkey How to call Settings.System.canWrite(context) (Android)

I'm using Delphi 10.3 Community Edition and want to use the WRITE_SETTINGS in my application to set the brightness.
I could get it managed to implement this procedure to call the settings dialog:
procedure RequestWriteSettings;
var
Intent: JIntent;
begin
Intent := TJIntent.JavaClass.init(TJSettings.JavaClass.ACTION_MANAGE_WRITE_SETTINGS);
TAndroidHelper.Activity.startActivity(Intent);
end;
I can call this procedure in my application, the dialog appears and I can set the necessary permissions.
But I don't want to call this procedure permanently, because that's not user friendly.
I need to check if the WRITE_SETTINGS permission is already set, but I don't know how to implement this in Delphi/Firemonkey.
What I could find is that one has to call the "Settings.System.canWrite(context)" function, but I only can find samples for java.
Calling these kind of java routines in Delphi isn't that easy. I'm searching around already for some weeks and tried "things on my own", but still without success.
Can someone provide the code line how this routine has to be called in Delphi?
Thanks so much in advance!
MPage

Example code for checking WRITE_SETTINGS:
uses
Androidapi.JNI.GraphicsContentViewText, Androidapi.JNI.Provider, Androidapi.JNI.Net, Androidapi.Helpers;
procedure TForm1.RequestWriteSettingsButtonClick(Sender: TObject);
begin
if not TJSettings_System.JavaClass.canWrite(TAndroidHelper.Context) then
StartWritePermissionsActivity
else
ShowMessage('System says app can write settings');
end;
procedure TForm1.StartWritePermissionsActivity;
var
LIntent: JIntent;
begin
LIntent := TJIntent.JavaClass.init(TJSettings.JavaClass.ACTION_MANAGE_WRITE_SETTINGS);
LIntent.setData(TJnet_Uri.JavaClass.parse(StringToJString('package:').concat(TAndroidHelper.Context.getPackageName)));
TAndroidHelper.Context.startActivity(LIntent);
end;

In the meanwhile I found a solution for myself, but I think Dave's is better. ;-)
That's what I found with the "trial and error" method:
function HasWriteSettings: Boolean;
begin
// Call canWrite to check for permission WRITE_SETTINGS
Result := TJSettings_System.JavaClass.canWrite(TAndroidHelper.Context.getApplicationContext);
end;

Barcode reading Delphi xe7, event after intent not triggering

In my app, developed with XE7 for Android/iOS, I have a form for scanning barcodes. Upon a found barcode, my app validates whether it is an acceptable barcode or not. Following tutorials here: http://www.fmxexpress.com/qr-code-scanner-source-code-for-delphi-xe5-firemonkey-on-android-and-ios/
Currently I am testing on Android and I am able to integrate scanning and reading of barcodes, but the 'onBarCode' event does not fire when returned from the shared Activity of finding the barcode. Same code worked well with previous versions of Rad Studio ( XE4, XE5, XE6) but now in XE7 it does not.
Here are some snippets of code:
...
begin
Scanner := TAndroidBarcodeScanner.Create(true);
Scanner.OnBarCode := BarcodeHandler;
Scanner.Scan;
end;
procedure TmScannerForm.BarcodeHandler(Sender: TAndroidBarcodeScanner;
BarCode: String);
begin
text1.Text := Barcode;
memo1.PasteFromClipboard;
AddBarcode(BarCode, true);
end;
AddBarCode is the even I used to validate and add barcode to a list, but I didnt include it, because that code isn't the problem - it's not even triggering. The Text1.text:=Barcode and memo1.paseFromClipboard were in their for validating the even wasn't firing too. I can confirm the barcodes are being read because if I tap and manually paste, the barcode shows.
Why is this not working on XE7 as it did in previous versions of Rad Studio?

Andrea Magni has a more elegant solution than the timer on his blog based on event handling.
I would comment to send the link but I don't have enough reputation.
The link to his blog is :
http://blog.delphiedintorni.it/2014/10/leggere-e-produrre-barcode-con-delphi.html
Maybe this can help you. The blog is in Italian though but the sources are provided and are explaining by themselves.

There is a source code fragment on http://john.whitham.me.uk/xe5/ which looks useable (based on Zxing):
intent := tjintent.Create;
intent.setAction(stringtojstring('com.google.zxing.client.android.SCAN'));
sharedactivity.startActivityForResult(intent,0);
The code in the linked article also shows how to receive the Intent result. (I don't work with Delphi on Android so I am not sure if that part uses a best practice - TTKRBarCodeScanner uses a workaround with a Timer and the Clipboard).
I would try this as an alternative to see if works.

This code works to me!
Set timer enabled to true when you run your scan code
procedure Tform.Timer1Timer(Sender: TObject);
begin
if (ClipService.GetClipboard.ToString <> '') then
begin
timer1.Enabled:=false;
zSearch.Text := ClipService.GetClipboard.ToString;
//Do what you need
end;
end;

This code to me works fine!
in andorid.BarcodeScanner
function TAndroidBarcodeScanner.HandleAppEvent(AAppEvent: TApplicationEvent;
AContext: TObject): Boolean;
var
aeBecameActive : TApplicationEvent;
begin
aeBecameActive := TApplicationEvent.BecameActive;
if FMonitorClipboard and (AAppEvent = aeBecameActive) then
begin
GetBarcodeValue;
end;
end;

Delphi XE5 Anonymous ShowModal doesn't work as expected

I am a newbie to Delphi XE5 and currently developing Android platform applications on my Windows desktop using Delphi XE5.
I have two forms(Form1 and Form2) and tried to show Form2 in modal way on Form1 according to the way showed in Marco's RAD Blog(http://blog.marcocantu.com/blog/xe5_anonymous_showmodal_android.html).
But result was not as expected.
procedure TForm1.Button1Click(Sender: TObject);
var
frm2: TForm2;
begin
frm2 := TForm2.Create(nil);
ShowMessage('before frm2.ShowModal...');
frm2.ShowModal (
procedure(ModalResult: TModalResult)
begin
if ModalResult = mrOK then
if frm2.ListBox1.ItemIndex >= 0 then
edit1.Text := frm2.ListBox1.Items [frm2.ListBox1.ItemIndex];
frm2.DisposeOf;
end
);
ShowMessage('after frm2.ShowModal...');
end;
I wrote above code and run the application on an Android device.
I clicked the Button1, then I got the messagebox "before frm2.ShowModal... ", next "after frm2.ShowModal...", and then Form2 was showed.
I expect that the order should be 1)"before frm2.ShowModal... " message, 2) Form2 being showed, and 3) "after frm2.ShowModal..." message.
What's wrong with me?

The call to the anonymous ShowModal is not blocking, which means that any code after the ShowModal will be executed first.
One note here. Calling frm2.DisposeOf is wrong.
You must use this pattern:
declare
procedure TFrm2.FormClose(Sender: TObject; var Action: TCloseAction);
begin
Action := TCloseAction.caFree;
end;
See http://www.malcolmgroves.com/blog/?p=1585.
The documentation has been corrected in XE7, Using FireMonkey Modal Dialog Boxes, but this pattern can be used in all Delphi versions.
Conclusion: if you want to execute code after the modal dialog is closed, put that code inside the anonymous method.