Forum > CustomDrawn
[SOLVED] TEdit key press events in customdrawn LCLWidgetType
zeljko:
--- Quote from: lagprogramming on April 13, 2023, 05:03:06 pm ---When running an empty form in QT, are both OnFormUTF8KeyPress and OnFormKeyPress triggered when pressing a key? If the answer is yes, is OnFormUTF8KeyPress triggered before OnFormKeyPress?
--- End quote ---
1.Yes
2.Yes
Applies to Qt, Qt5 and Qt6 widgetsets.
lagprogramming:
Follow up to commit fa8f6ffa: LCL: Make AUTF8Char a var parameter in function LCLSendUTF8KeyPress. Issue...
lcl/interfaces/customdrawn/customdrawnprivate.pas has procedure CallbackKeyChar(AWindowHandle: TCDForm; AKeyData: Word; AChar: TUTF8Char);
The following code fixes the key events:
--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---procedure CallbackKeyChar(AWindowHandle: TCDForm; AKeyData: Word; AChar: TUTF8Char);var lTarget: TWinControl; lCharCode: Word;begin lTarget := AWindowHandle.GetFocusedControl(); {$ifdef VerboseCDEvents} DebugLn(Format('CallbackKeyChar FocusedControl=%s:%s', [lTarget.Name, lTarget.ClassName])); {$endif} if lTarget = nil then Exit; // Fixes a crash if Length(AChar) = 1 then lCharCode := Byte(AChar[1]) else lCharCode := 0; if AChar<>'' then LCLSendUTF8KeyPress(lTarget, AChar, False); if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True); // If this is a interface control, send the message to the main LCL control too if IsIntfControl(lTarget) then begin lTarget := lTarget.Parent; if AChar<>'' then LCLSendUTF8KeyPress(lTarget, AChar, False); if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True); end;end;But before providing a patch I have a question. lcl/include/wincontrol.inc contains the following procedures:
--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---procedure TWinControl.KeyDown(var Key: Word; Shift: TShiftState);begin if Assigned(FOnKeyDown) then FOnKeyDown(Self, Key, Shift); if Key <> 0 then DoCallKeyEventHandler(chtOnKeyDown, Key, Shift);end;
--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---procedure TWinControl.KeyPress(var Key: char);begin if Assigned(FOnKeyPress) then FOnKeyPress(Self, Key);end;
--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---procedure TWinControl.KeyUp(var Key: Word; Shift : TShiftState);begin if Assigned(FOnKeyUp) then FOnKeyUp(Self, Key, Shift);end;
--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---procedure TWinControl.UTF8KeyPress(var UTF8Key: TUTF8Char);begin if Assigned(FOnUTF8KeyPress) then FOnUTF8KeyPress(Self, UTF8Key);end; Regarding the modified procedure CallbackKeyChar, before the comment line "// If this is a interface control, send the message to the main LCL control too" the value of AChar can be modified at line "if AChar<>'' then LCLSendUTF8KeyPress(lTarget, AChar, False);". Also the value of lCharCode can be modified too at line "if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True);".
After the comment line the message is sent to the main LCL control only if AChar<>'' for LCLSendUTF8KeyPress and only if lCharCode <> 0 for LCLSendCharEvent. Is this the right behavior? This means that you can cancel sending the messages further to the LCL controls by modifying in one of the OnKey* events the value of AChar to '' or the value of lCharCode to 0. Look at the content of procedure TWinControl.KeyDown(var Key: Word; Shift: TShiftState); as it has that "if Key <> 0 then DoCallKeyEventHandler(chtOnKeyDown, Key, Shift);" line. Also, function TWinControl.DoKeyPress(var Message : TLMKey): Boolean; has an "if Char(CharCode) = #0 then Exit;" line.
lagprogramming:
The following patch fixes the bug.
--- Code: Pascal [+][-]window.onload = function(){var x1 = document.getElementById("main_content_section"); if (x1) { var x = document.getElementsByClassName("geshi");for (var i = 0; i < x.length; i++) { x[i].style.maxHeight='none'; x[i].style.height = Math.min(x[i].clientHeight+15,306)+'px'; x[i].style.resize = "vertical";}};} ---diff --git a/lcl/interfaces/customdrawn/customdrawnprivate.pas b/lcl/interfaces/customdrawn/customdrawnprivate.pasindex bcf33be060..7a95139583 100644--- a/lcl/interfaces/customdrawn/customdrawnprivate.pas+++ b/lcl/interfaces/customdrawn/customdrawnprivate.pas@@ -288,7 +288,7 @@ end; procedure CallbackKeyChar(AWindowHandle: TCDForm; AKeyData: Word; AChar: TUTF8Char); var lTarget: TWinControl;- lCharCode: Word = 0;+ lCharCode: Word; begin lTarget := AWindowHandle.GetFocusedControl(); {$ifdef VerboseCDEvents}@@ -296,17 +296,20 @@ begin {$endif} if lTarget = nil then Exit; // Fixes a crash- if Length(AChar) = 1 then lCharCode := Word(AChar[1]);+ if Length(AChar) = 1 then+ lCharCode := Byte(AChar[1])+ else+ lCharCode:=0; -// if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True);- LCLSendUTF8KeyPress(lTarget, AChar, False);+ if AChar<>'' then LCLSendUTF8KeyPress(lTarget, AChar, False);+ if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True); // If this is a interface control, send the message to the main LCL control too if IsIntfControl(lTarget) then begin lTarget := lTarget.Parent;-// if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True);- LCLSendUTF8KeyPress(lTarget, AChar, False);+ if AChar<>'' then LCLSendUTF8KeyPress(lTarget, AChar, False);+ if lCharCode <> 0 then LCLSendCharEvent(lTarget, lCharCode, AKeyData, True, False, True); end; end;
AlexTP:
Posted to bugtracker,
https://gitlab.com/freepascal.org/lazarus/lazarus/-/issues/40221
Josh:
Hi
Am i missing something, maybe its optimization.
You remove =0 in lCharCode: Word = 0;
then set it to zero in
if Length(AChar) = 1 then
lCharCode := Byte(AChar[1])
else
lCharCode:=0;
Also why casting a word to byte?
Navigation
[0] Message Index
[#] Next page
[*] Previous page