How to  draw Controls on canvas at linux? Or other ways to draw check
box on VST
lazarus / 39-Graphics

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Pixelmak · 2020-10-08 13:41

Usually at the Windows i am using UxTheme library.

Like this
Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
TxpLoginRegisterForm.GridAfterCellPaint(Sender: TBaseVirtualTree; 
TargetCanvas: TCanvas; Node: PVirtualNode; Column: TColumnIndex; 
const CellRect: TRect);var  r: TRect;  size: TSize;  h: HTHEME;  
data: PGridData;const  PADDING = 4;begin  if Column = IsWebColumn
then  begin    r := CellRect;     data := Grid.GetNodeData(Node);   
size.cx := GetSystemMetrics(SM_CXMENUCHECK);    size.cy :=
GetSystemMetrics(SM_CYMENUCHECK);     h :=
OpenThemeData(Sender.Handle, 'BUTTON');     GetThemePartSize(h,
TargetCanvas.Handle, BP_CHECKBOX, CBS_CHECKEDNORMAL, nil, TS_DRAW,
size);    r.Top    := CellRect.Top + (CellRect.Bottom - CellRect.Top -
size.cy) div 2;    r.Bottom := r.Top + size.cy;    r.Left   := r.Left
+ PADDING;    r.Right  := r.Left + size.cx;     if data^.IsWeb=1 then 
    DrawThemeBackground(h, TargetCanvas.Handle, BP_CHECKBOX,
CBS_CHECKEDNORMAL, r, nil)    else      DrawThemeBackground(h,
TargetCanvas.Handle, BP_CHECKBOX, CBS_UNCHECKEDNORMAL, r, nil);    
CloseThemeData(h);  end;end; 
Is there a way to do the same for Linux? Or other ways to draw a
checkbox?

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wp · 2020-10-08 14:03

Checkbox theme drawing should be active in VTV by default
(CheckImageKind = dkSystemDefault), AFIK there is no need to draw
checkbox manually for this purpose.

In general, theme support is handled in the LCL in a cross-platform
way by the unit "themes" and the ThemeServices methods.

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Pixelmak · 2020-10-08 14:45

Quote from: wp on October 08, 2020, 04:03:23 pmCheckbox theme drawing
should be active in VTV by default (CheckImageKind = dkSystemDefault),
AFIK there is no need to draw checkbox manually for this purpose.

I am using TVirtualStringTree where I have many columns, in each of
which I need to draw a checkbox. But "CheckImageKind" adds a checkbox
only to the root column.

Quote from: wp on October 08, 2020, 04:03:23 pmIn general, theme
support is handled in the LCL in a cross-platform way by the unit
"themes" and the ThemeServices methods.

Excellent! That's what I was looking for! Thank you so much!

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i procedure
TxpLoginRegisterForm.GridAfterCellPaint(Sender: TBaseVirtualTree; 
TargetCanvas: TCanvas; Node: PVirtualNode; Column: TColumnIndex; 
const CellRect: TRect);var  r: TRect;  size: TSize;  data:
PGridData;   Details: TThemedElementDetails;const  PADDING = 4;begin 
if Column = IsWebColumn then  begin    r := CellRect;     data :=
Grid.GetNodeData(Node);    size.cx :=
GetSystemMetrics(SM_CXMENUCHECK);    size.cy :=
GetSystemMetrics(SM_CYMENUCHECK);     r.Top    := CellRect.Top +
(CellRect.Bottom - CellRect.Top - size.cy) div 2;    r.Bottom := r.Top
+ size.cy;    r.Left   := r.Left + PADDING;    r.Right  := r.Left +
size.cx;     if data^.IsWeb=1 then      Details :=
ThemeServices.GetElementDetails(tbCheckBoxCheckedNormal)    else     
Details :=
ThemeServices.GetElementDetails(tbCheckBoxUncheckedNormal);    
ThemeServices.DrawElement(TargetCanvas.Handle, Details, r, nil);    
CloseThemeData(h);  end;end;