lazarus/lcl/include/customlabel.inc
2005-11-03 15:03:08 +00:00

398 lines
12 KiB
PHP

{%MainUnit ../stdctrls.pp}
{******************************************************************************
TCustomLabel
******************************************************************************
*****************************************************************************
* *
* This file is part of the Lazarus Component Library (LCL) *
* *
* See the file COPYING.LCL, included in this distribution, *
* for details about the copyright. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. *
* *
*****************************************************************************
TODO:
- Enable Tabbing/Focusing to focus FocusControl
- Enable Escaped '&' Shortcut to focus FocusControl
- Compare/Match AutoSize to Delphi/Kylix's
- ?? Check For Full Delphi/Kylix Compatibility
}
procedure TCustomLabel.CalcSize(var AWidth, AHeight: integer);
{ assumes: (Parent <> nil) and Parent.HandleAllocated }
var
R : TRect;
DC : hDC;
Flags: Cardinal;
OldFont: HGDIOBJ;
begin
DC := GetDC(Parent.Handle);
try
R := Rect(0,0, Width, Height);
OldFont:=SelectObject(DC, Font.Handle);
Flags:=DT_CalcRect or DT_NoPrefix;
if WordWrap then inc(Flags,DT_WordBreak);
DrawText(DC, PChar(Caption), Length(Caption), R, Flags);
SelectObject(DC, OldFont);
// add one to be able to display disabled label
AWidth := R.Right - R.Left + 1;
AHeight := R.Bottom - R.Top + 1;
finally
ReleaseDC(Parent.Handle, DC);
end;
end;
Procedure TCustomLabel.DoAutoSize;
var
NewWidth, NewHeight: integer;
CurAnchors: TAnchors;
begin
//debugln('TCustomLabel.DoAutoSize ',DbgSName(Self),' AutoSizing=',dbgs(AutoSizing),' AutoSize=',dbgs(AutoSize),' Parent=',DbgSName(Parent),' csLoading=',dbgs(csLoading in ComponentState),' Parnet.HandleAllocated=',dbgs((Parent<>nil) and (Parent.HandleAllocated)));
if OptimalFill and (not AutoSize) then begin
AdjustFontForOptimalFill;
exit;
end;
if AutoSizeDelayed then
exit;
AutoSizing := True;
try
CalcSize(NewWidth, NewHeight);
//debugln('TCustomLabel.DoAutoSize ',dbgs(Left),' ',dbgs(Top),' ',dbgs(NewWidth),' ',dbgs(NewHeight));
CurAnchors:=[];
if Align in [alLeft,alRight,alBottom,alTop,alClient] then
CurAnchors:=AnchorAlign[Align];
CurAnchors:=Anchors+CurAnchors;
if CurAnchors*[akLeft,akRight]=[akLeft,akRight] then
NewWidth:=Width;
if CurAnchors*[akTop,akBottom]=[akTop,akBottom] then
NewHeight:=Height;
SetBoundsKeepBase(Left, Top, NewWidth, NewHeight);
finally
AutoSizing := False;
end;
end;
Procedure TCustomLabel.SetAlignment(Value : TAlignment);
begin
//debugln('TCustomLabel.SetAlignment Old=',dbgs(ord(Alignment)),' New=',dbgs(ord(Value)),' csLoading=',dbgs(csLoading in ComponentState));
if FAlignment <> Value then begin
FAlignment := Value;
Invalidate;
end;
end;
procedure TCustomLabel.Notification(AComponent : TComponent; Operation : TOperation);
begin
inherited Notification(AComponent, Operation);
if (AComponent = FFocusControl) and (Operation = opRemove) then
FFocusControl:= nil;
end;
procedure TCustomLabel.SetFocusControl(Value : TWinControl);
begin
if Value <> FFocusControl then begin
FFocusControl:= Value;
if Value <> nil then Value.FreeNotification(Self);
end;
end;
procedure TCustomLabel.WMActivate(var Message: TLMActivate);
begin
if (FFocusControl <> nil) and (FFocusControl.CanFocus) then
FFocusControl.SetFocus;
end;
Function TCustomLabel.GetAlignment : TAlignment;
begin
Result := FAlignment;
end;
Procedure TCustomLabel.SetShowAccelChar(Value : Boolean);
begin
If FShowAccelChar <> Value then begin
FShowAccelChar := Value;
Invalidate;
end;
end;
procedure TCustomLabel.TextChanged;
begin
Invalidate;
AdjustSize;
end;
procedure TCustomLabel.Resize;
begin
inherited Resize;
if OptimalFill and (not AutoSize) then
AdjustFontForOptimalFill;
end;
Function TCustomLabel.GetShowAccelChar : Boolean;
begin
Result := FShowAccelChar;
end;
function TCustomLabel.CanTab: boolean;
begin
Result:=false;
end;
constructor TCustomLabel.Create(TheOwner: TComponent);
begin
inherited Create(TheOwner);
Font.OnChange := @FontChange;
ControlStyle := [csSetCaption, csOpaque, csClickEvents, csDoubleClicks,
csReplicatable];
Width := 65;
Height := 17;
FShowAccelChar := True;
Color := clNone;
AutoSize:=true;
end;
function TCustomLabel.GetTransparent: boolean;
begin
Result := Color = clNone;
end;
{------------------------------------------------------------------------------
Method: TCustomLabel.SetLayout
Params: None
Returns: Nothing
------------------------------------------------------------------------------}
procedure TCustomLabel.SetLayout(Value: TTextLayout);
begin
if FLayout <> Value then begin
FLayout:= Value;
Invalidate;
end;
end;
procedure TCustomLabel.SetTransparent(NewTransparent: boolean);
begin
if NewTransparent then
Color := clNone;
end;
{------------------------------------------------------------------------------
Method: TCustomLabel.SetWordWrap
Params: None
Returns: Nothing
------------------------------------------------------------------------------}
procedure TCustomLabel.SetWordWrap(Value: Boolean);
begin
if fWordWrap <> value then begin
fWordWrap:= value;
Invalidate;
end;
end;
function TCustomLabel.DialogChar(var Message: TLMKey): boolean;
begin
Result := false;
if not FShowAccelChar then exit;
if FFocusControl = nil then exit;
if IsAccel(Message.CharCode, Caption) and FFocusControl.CanFocus then
begin
Result := true;
FFocusControl.SetFocus;
end else
Result := inherited;
end;
procedure TCustomLabel.Loaded;
begin
inherited Loaded;
AdjustSize;
end;
{-------------------------------------------------------------------------------
function TCustomLabel.CalcFittingFontHeight(const TheText: string;
MaxWidth, MaxHeight: Integer;
var FontSize, NeededWidth, NeededHeight: integer): Boolean;
Calculates the maximum font size for TheText to fit into MaxWidth and
MaxHeight.
-------------------------------------------------------------------------------}
function TCustomLabel.CalcFittingFontHeight(const TheText: string;
MaxWidth, MaxHeight: Integer;
var FontHeight, NeededWidth, NeededHeight: integer): Boolean;
var
R : TRect;
DC : hDC;
Flags: Cardinal;
OldFont: HGDIOBJ;
MinFontHeight: Integer;
MaxFontHeight: Integer;
AFont: TFont;
CurFontHeight: LongInt;
begin
Result:=false;
if AutoSizeDelayed or (TheText='') or (MaxWidth<1) or (MaxHeight<1) then exit;
AFont:=TFont.Create;
AFont.Assign(Font);
CurFontHeight:=AFont.Height;
MinFontHeight:=5;
MaxFontHeight:=MaxHeight*2;
if (CurFontHeight<MinFontHeight) or (CurFontHeight>MaxFontHeight) then
CurFontHeight:=(MinFontHeight+MaxFontHeight) div 2;
Flags:=DT_CalcRect or DT_NoPrefix;
if WordWrap then inc(Flags,DT_WordBreak);
// give a clipping rectangle with space, so that the bounds returned by
// DrawText can be bigger and we know, the tried font is too big.
R := Rect(0,0, MaxWidth, MaxHeight*2);
DC := GetDC(Parent.Handle);
try
while (MinFontHeight<=MaxFontHeight) and (CurFontHeight>=MinFontHeight)
and (CurFontHeight<=MaxFontHeight) do begin
AFont.Height:=CurFontHeight; // NOTE: some TFont do not allow any integer
//debugln('TCustomLabel.CalcFittingFontHeight A ',dbgs(MinFontHeight),'<=',dbgs(AFont.Height),'<=',dbgs(MaxFontHeight));
OldFont:=SelectObject(DC, AFont.Handle);
DrawText(DC, PChar(TheText), Length(TheText), R, Flags);
SelectObject(DC, OldFont);
NeededWidth := R.Right - R.Left;
NeededHeight := R.Bottom - R.Top;
//debugln('TCustomLabel.CalcFittingFontHeight B NeededWidth=',dbgs(NeededWidth),' NeededHeight=',dbgs(NeededHeight),' MaxWidth=',dbgs(MaxWidth),' MaxHeight=',dbgs(MaxHeight));
if (NeededWidth>0) and (NeededHeight>0)
and (NeededWidth<=MaxWidth) and (NeededHeight<=MaxHeight) then begin
// TheText fits into the bounds
if (not Result) or (FontHeight<AFont.Height) then
FontHeight:=AFont.Height;
Result:=true;
MinFontHeight:=CurFontHeight;
// -> try bigger (binary search)
CurFontHeight:=(MaxFontHeight+CurFontHeight+1) div 2; // +1 to round up
if CurFontHeight=MinFontHeight then break;
end else begin
// TheText does not fit into the bounds
MaxFontHeight:=CurFontHeight-1;
// -> try smaller (binary search)
CurFontHeight:=(MinFontHeight+CurFontHeight) div 2;
end;
end
finally
ReleaseDC(Parent.Handle, DC);
AFont.Free;
end;
end;
{-------------------------------------------------------------------------------
function TCustomLabel.AdjustFontForOptimalFill: Boolean;
Maximizes Font.Height
Return true if Font.Height changed.
-------------------------------------------------------------------------------}
function TCustomLabel.AdjustFontForOptimalFill: Boolean;
var
NeededWidth: Integer;
NeededHeight: Integer;
NewFontHeight: Integer;
OldFontHeight: LongInt;
begin
Result:=false;
if not CalcFittingFontHeight(Caption,Width,Height,NeededWidth,NeededHeight,
NewFontHeight) then exit;
if Font.Height=NewFontHeight then exit;
//debugln('TCustomLabel.AdjustFontForOptimalFill OldFontHeight=',dbgs(Font.Height),' NewFontHeight=',dbgs(NewFontHeight));
OldFontHeight:=Font.Height;
Font.Height:=NewFontHeight;
Result:=OldFontHeight<>Font.Height;
end;
Procedure TCustomLabel.Paint;
var
TR : TTextStyle;
R : TRect;
TextLeft, TextTop: integer;
lTextWidth, lTextHeight: integer;
begin
R := Rect(0,0,Width,Height);
With Canvas do begin
Color := Self.Color;
Font := Self.Font;
if Color<>clNone then
FillRect(R);
{
If BorderStyle <> sbsNone then begin
InflateRect(R,-2,-2);
Pen.Style := psSolid;
If BorderStyle = sbsSunken then
Pen.Color := clBtnShadow
else
Pen.Color := clBtnHighlight;
MoveTo(0, 0);
LineTo(Width - 1,0);
MoveTo(0, 0);
LineTo(0,Height - 1);
If BorderStyle = sbsSunken then
Pen.Color := clBtnHighlight
else
Pen.Color := clBtnShadow;
MoveTo(0,Height - 1);
LineTo(Width - 1,Height - 1);
MoveTo(Width - 1, 0);
LineTo(Width - 1,Height);
end;
}
//Brush.Color:=clRed;
//FillRect(R);
FillChar(TR,SizeOf(TR),0);
With TR do begin
Alignment := Self.Alignment;
WordBreak := True;
Clipping := True;
ShowPrefix := ShowAccelChar;
SystemFont:=false;
end;
CalcSize(lTextWidth, lTextHeight);
TextLeft := R.Left;
case Layout of
tlTop: TextTop := R.Top;
tlCenter: TextTop := (R.Bottom - R.Top - lTextHeight) div 2;
tlBottom: TextTop := R.Bottom - R.Top - lTextHeight;
end;
//debugln('TCustomLabel.Paint ',dbgs(Alignment=tacenter),' ',dbgs(Layout=tlCenter),' ',dbgs(TextLeft),' TextTop=',dbgs(TextTop),' ',dbgs(R));
if not Enabled then begin
Font.Color := clBtnHighlight;
textRect(R, TextLeft + 1, TextTop + 1, Caption, TR);
Font.color := clBtnShadow;
end;
TextRect(R, TextLeft, TextTop, Caption, TR)
end;
end;
Procedure TCustomLabel.FontChange(Sender : TObject);
begin
If Caption <> '' then
Invalidate;
end;
procedure TCustomLabel.SetOptimalFill(const AValue: Boolean);
begin
if FOptimalFill=AValue then exit;
FOptimalFill:=AValue;
if OptimalFill and AutoSize then
AutoSize:=false;
Invalidate;
end;
// included by stdctrls.pp