[SOLVED] SIGSEGV on free pointer Tframe

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superc:
Hello,
I want to create dinamically tframe on tpanel and free it for loading another; I use this code for create TFrame:

--- 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 TMonitorForm.Button1Click(Sender: TObject);var hwnd: TFrame;begin hwnd := CreateFrameAndHostPanel(pnlRight, pnlRight, pnlRight); pntFrame := @hwnd; ShowMessage(IntToStr(TFrameLEDMonitor(pntFrame^).getNumber)); TFrameLEDMonitor(pntFrame^).Free; end; function TMonitorForm.CreateFrameAndHostPanel(_Owner: TComponent; _Parent: TWinControl; _Panel: TPanel): TFrame;begin Result := FrameLcd.TFrameLCDMonitor.Create(Owner); Try Result.Parent := _Parent; Except FreeAndNil(Result); raise; End;end;
In this code Free works well and free pointed frame, but if I move free line of code in another button like as:

--- 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 TMonitorForm.Button2Click(Sender: TObject);begin TFrameLEDMonitor(pntFrame^).Free;end;
I get and SIGSEGV error and access violation; pntFrame is declared in public section and is typed as:

--- 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";}};} ---type pointerTFrame = ^TFrame;
I don't understand why,

thanks in advance.

marcov:
You specified an owner when creating the frame. An owner (I assume the form) frees the owned class (the frame) on shutdown.

IIRC you can remove the owner registration using TComponent.RemoveComponent

superc:
Excuse Marcov, I don't understand; i must remove owner as default passed with RemoveComponent?

Thanks

howardpc:
Try declaring your public instance reference simply as

--- 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";}};} ---tempFrame: TFrameLEDMonitor;and drop the local variable from your click event handler:
--- 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 TMonitorForm.Button1Click(Sender: TObject);begin tempFrame := CreateFrameAndHostPanel(...); ShowMessage(...); tempFrame.Free; tempFrame := Nil;end;

superc:

--- Quote from: howardpc on May 12, 2021, 10:38:33 am ---Try declaring your public instance reference simply as

--- 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";}};} ---tempFrame: TFrameLEDMonitor;and drop the local variable from your click event handler:
--- 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 TMonitorForm.Button1Click(Sender: TObject);begin tempFrame := CreateFrameAndHostPanel(...); ShowMessage(...); tempFrame.Free; tempFrame := Nil;end;
--- End quote ---

Works fine with

--- 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";}};} --- public { public declarations } pntFrame: TFrame;
I've 5 Frame different, Thank you very much...

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