Delphi Self-writing components: can set the color of the button (change to Bs_ownerdraw style, and then Cn_drawitem)

• Unit Colorbutton;
• Interface
• Uses
• Windows, Messages, Sysutils, Classes, Graphics, Controls,
• Stdctrls;
• Type
• Tcolorbutton = Class (TButton)
• Private
• //Add color property, default Clwhite
• {Private declarations}
• Fcolor:tcolor;
• Fcanvas:tcanvas;
• Isfocused:boolean;
• procedure SetColor (value:tcolor);
• procedure Cndrawitem (var message:twmdrawitem); Message Cn_drawitem;
• protected
• {Protected declarations}
• procedure CreateParams (var params:tcreateparams); override;
• procedure SetButtonStyle (Adefault:boolean); override;
• Public
• {public declarations}
• Constructor Create (aowner:tcomponent); override;
• destructor destroy;override;
• published
• {Published declarations}
• Property Color:tcolor Read Fcolor write setcolor default clwhite;
• end;
• Procedure Register;
• Implementation
• //**********************************
• Borland/delphi7/source/vcl/checklst.pas can make reference
• //**********************************
• Registration functions automatically added by the system
• Procedure Register;
• Begin
• Registercomponents (' Additional ', [Tcolorbutton]);
• End
• Add Constructor ***************
• Constructor Tcolorbutton. Create (aowner:tcomponent);
• Begin
• inherited Create (Aowner);
• Fcanvas:=tcanvas. Create;
• Fcolor:=clwhite; //Set Default color
• End
• Add a destructor ***************
• destructor Tcolorbutton. Destroy;
• Begin
• Fcanvas. Free;
• inherited Destroy;
• End
• Defines the button style, which must be redefined as a self-portrait button * * * *
• Procedure Tcolorbutton. CreateParams (var params:tcreateparams);
• Begin
• inherited CreateParams (Params);
• With Params do style:=style or Bs_ownerdraw;
• End
• Attribute Write Method * * * *
• Procedure Tcolorbutton. SetColor (Value:tcolor);
• Begin
• Fcolor:=value;
• Invalidate; //Full Redraw control
• End
• Set Button Status * * * *
• Procedure Tcolorbutton. SetButtonStyle (Adefault:boolean);
• Begin
• if adefault<>isfocused Then
• begin
• Isfocused:=adefault;
• Refresh;
• end;
• End
• Draw button * * * *
• Procedure Tcolorbutton. Cndrawitem (var message:twmdrawitem);
• Var
• Isdown,isdefault:boolean;
• Arect:trect;
• Flags:longint;
• Drawitemstruct:tdrawitemstruct;
• Wh:tsize;
• Begin
• /////////////////////////////////////////
• Drawitemstruct:=message. drawitemstruct^;
• Fcanvas. Handle: = Drawitemstruct. HDC;
• Arect: = Clientrect;
• With drawitemstruct do
• begin
• Isdown: = itemState and ods_selected <> 0;
• IsDefault: = itemState and ods_focus <> 0;
• end;
• Flags: = Dfcs_buttonpush or dfcs_adjustrect;
• if Isdown then flags: = Flags or dfcs_pushed;
• if Drawitemstruct. ItemState and ods_disabled <> 0 Then
• Flags: = Flags or dfcs_inactive;
• if IsFocused or IsDefault Then
• begin
• //button to draw the state when the focus is given
• Fcanvas. Pen. Color: = clwindowframe;
• Fcanvas. Pen. Width: = 1;
• Fcanvas. Brush. Style: = bsclear;
• Fcanvas. Rectangle (Arect. Left, Arect. Top, Arect. Right, Arect. Bottom);
• Inflaterect (Arect,-1,-1);
• end;
• Fcanvas. Pen. Color: = Clbtnshadow;
• Fcanvas. Pen. Width: = 1;
• Fcanvas. Brush. Color: = Fcolor;
• if Isdown then begin
• //The State of the button is drawn when pressed
• Fcanvas. Rectangle (Arect. Left, Arect. Top, Arect. Right, Arect. Bottom);
• Inflaterect (Arect,-1,-1);
• End Else
• //Draw a button that is not pressed
• Drawframecontrol (drawitemstructHDC, Arect, Dfc_button, Flags);
• Fcanvas. FillRect (arect);
• //Draw caption text content
• Fcanvas. Font: = Self. Font;
• Arect:=clientrect;
• Wh:=fcanvas. Textextent (Caption);
• Fcanvas. Pen. Width: = 1;
• Fcanvas. Brush. Style: = bsclear;
• if not Enabled Then
• The begin //button should be painted once more caption text when it fails
• Fcanvas. Font. Color: = clbtnhighlight;
• Fcanvas. TextOut (Width Div 2)-(WH. CX Div 2) +1,
• (Height div 2)-(WH. Cy Div 2) +1,
• Caption);
• Fcanvas. Font. Color: = Clbtnshadow;
• end;
• Fcanvas. TextOut (Width Div 2)-(WH. CX Div 2), (height div 2)-(WH. Cy Div 2), Caption);
• //Draw the inner box dashed when getting focus
• if IsFocused and IsDefault Then
• begin
• Arect: = Clientrect;
• Inflaterect (Arect,-4,-4);
• Fcanvas. Pen. Color: = clwindowframe;
• Fcanvas. Brush. Color: = Fcolor;
• DrawFocusRect (Fcanvas. Handle, arect);
• end;
• Fcanvas. Handle: = 0;
• End
  
• End.

http://blog.csdn.net/aroc_lo/article/details/3070530

Http://www.fx114.net/qa-183-149306.aspx

Delphi Self-writing components: can set the color of the button (change to Bs_ownerdraw style, and then Cn_drawitem)