Add CocoaWidgetSet.GetTextExtentPointF

[AlexTP]

I need the Cocoa method to get _floating number_ width of a given string, ie Double value. I suggest to add to Cocoa. I tried this code, and my demo crashes (I cannot debug it yet, problem with fpcupdeluxe on macOS)

Pls correct my code and add it to Laz.

1) cocoawinapi.inc

Code: Pascal  [Select][+][-]

1. function TCocoaWidgetSet.GetTextExtentPointF(DC: HDC; Str: PChar; Count: Integer; out AWidth, AHeight: Double): Boolean;
2. var
3.   ctx : TCocoaContext;
4. begin
5.   {$IFDEF VerboseWinAPI}
6.     DebugLn('[TCocoaWidgetSet.GetTextExtentPointF] DC: %x Str: %s Count: %d', [DC, Str, Count]);
7.   {$ENDIF}
8.   ctx:=CheckDC(DC);
9.   Result:=Assigned(ctx);
10.   if not Assigned(ctx) then Exit(False);
11.   Result := ctx.GetTextExtentPointF(Str, Count, AWidth, AHeight);
12.   {$IFDEF VerboseWinAPI}
13.     DebugLn('[TCocoaWidgetSet.GetTextExtentPointF] Size: %d,%d', [Size.cx, Size.cy]);
14.   {$ENDIF}
15. end;  

2) cocoagdiobjects.pas

Copy-paste from GetTextExtentPoint!

Code: Pascal  [Select][+][-]

1. function TCocoaContext.GetTextExtentPointF(AStr: PChar; ACount: Integer; out AWidth, AHeight: Double): Boolean;
2. var
3.   s : NSString;
4.   M : NSMutableAttributedString;
5.   r : NSRect;
6. begin
7.   AWidth := 0;
8.   AHeight := 0;
9.   {FText.SetText(AStr, ACount);
10.   Size := FText.GetSize;
11.   Result := True;}
12.   S := NSString( CFStringCreateWithBytesNoCopy(nil, AStr, ACount, kCFStringEncodingUTF8,
13.     false,
14.     kCFAllocatorNull));
15.   Result := Assigned(S);
16.   if not Result then Exit;
17.  
18.   M := NSMutableAttributedString.alloc.initWithString(S);
19.   Result := Assigned(M);
20.   if Result then
21.   begin
22.     FText.SetFontToStr(M);
23.     r := M.boundingRectWithSize_options(NSMakeSize(MaxInt, MaxInt), 0);
24.  
25.     AWidth := r.size.width;
26.     AHeight := r.Size.height;
27.     M.release;
28.   end;
29.   CFRelease(S);
30. end;
31.  

3) demo to test it. Zip.

[AlexTP]

I fixed the demo by myself. Now I see that char-width of '0' and all other ASCII chars is 7.801 pixels on macOS 10.8.
For several fonts: Courier, Monaco, Liberation Mono.
The same for all ASCII!