********一个自定义控件的问题*********

Question

constructor TMySpeedButton.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  Caption := Name;
end;

Answer 1

to hellion(恶人):目前的情况是每个控件的caption属性都是空,与TspeedButton类控件一样,以下是我的代码,帮忙找找bug.
unit RunButton;
interface
uses
  Windows, Messages, SysUtils,shellapi, Classes, Graphics, Controls, Forms, Dialogs,
  Buttons;
type
  TcommandLine=type string;
  TRunButton = class(TSpeedButton)
  private
    Fcaption:Tcaption;
    FcommandLine:TcommandLine;
    procedure SetCommandLine(value:TcommandLine);
    procedure setcaption(value:Tcaption);
    { Private declarations }
  protected
    { Protected declarations }
  public
    constructor create(Aowner:Tcomponent);override;
    procedure Click;override;
    { Public declarations }
  published
    property Caption:Tcaption read Fcaption write setcaption;
    property CommandLine:TcommandLine read FcommandLine write SetCommandLine;
    { Published declarations }
  end;
procedure Register;
implementation
procedure Register;
begin
  RegisterComponents('Samples', [TRunButton]);
end;
  procedure TrunButton.setcaption(value:Tcaption);
     begin
       inherited;
       Fcaption:=value;
       repaint;
     end;
  constructor TrunButton.create(Aowner:Tcomponent);
     begin
       inherited create(Aowner);
       setcaption(Name);
       width:=45;
       height:=45;
     end;
  Function IsExecutableFile(value:TcommandLine):boolean;
    begin
      result:=(uppercase(ExtractFileExt(value))='.EXE');
    end;
  procedure Trunbutton.SetCommandLine(value:TcommandLine);
    var
     Icon:Ticon;
    begin
      if not IsExecutableFile(value) then raise exception.Create(value+'不是一个可执行文件!');
      if not FileExists(value) then raise exception.Create(value+'文件不存在!');
      FcommandLine:=value;
      Icon:=Ticon.Create;
      try
         icon.Handle:=ExtractIcon(hinstance,Pchar(FcommandLine),0);
         with Glyph do
           begin
             canvas.brush.style:=bssolid;
             canvas.FillRect(canvas.cliprect);
             width:=icon.Width;
             height:=Icon.Height;
             canvas.Draw(0,0,icon);
           end;
      finally
          icon.Free;
      end;    
    end;
  function processexecute(commandline:TcommandLine;cshow:word):integer;
     var
       rslt:longbool;
       startupinfo:Tstartupinfo;
       processinfo:Tprocessinformation;
    begin
       fillchar(startupinfo,sizeof(Tstartupinfo),#0);
       with startupinfo do
         begin
           cb:=sizeof(Tstartupinfo);
           dwflags:=startf_useshowwindow or startf_forceonfeedback;
           wshowwindow:=cshow;
         end;
       rslt:=createprocess(pchar(commandline),nil,nil,nil,false,normal_priority_class,nil,
         nil,startupinfo,processinfo);
       if rslt then
           with processinfo do
             begin
               waitforinputidle(hprocess,infinite);
               closehandle(hthread);
               closehandle(hprocess);
               result:=0;
             end
       else
            result:=getlasterror;
    end;
  procedure Trunbutton.Click;
     var
       rean:word;
    begin
       inherited click;
       rean:=ProcessExecute(FcommandLine,sw_shownormal);
       if rean<>0 then
          raise exception.Create('错误地执行了程序:'+inttostr(rean));
    end;
end.

Answer 2

  protected
    procedure SetParent(AParent: TWinControl); override;
procedure TMySpeedButton.SetParent(AParent: TWinControl);
begin
  inherited;
  if AParent <> nil then
    Caption := Name;
end;

Answer 3

楼上,你好,问题解决了一半.
目前在object inspector中,caption值已经可以根据控件的加入而变化,但在控件上不显示caption值,如何处理?please help.

Answer 4

问题解决，全UNIT如下：unit runbutton;
interface
uses
  Windows, Messages, SysUtils,shellapi, Classes, Graphics, Controls, Forms, Dialogs,
  Buttons;
type
  TcommandLine=type string;
  TRunButton = class(TSpeedButton)
  private
    Fcaption:Tcaption;
    FcommandLine:TcommandLine;
    procedure SetCommandLine(value:TcommandLine);
    procedure setcaption(value:Tcaption);
    { Private declarations }
  protected
   
   procedure SetParent(AParent: TWinControl); override;
    { Protected declarations }
  public
    constructor create(Aowner:Tcomponent);override;
    procedure Click;override;
    { Public declarations }
  published
//    property Caption:Tcaption read Fcaption write setcaption;
    property CommandLine:TcommandLine read FcommandLine write SetCommandLine;
    { Published declarations }
  end;
procedure Register;
implementation
procedure TrunButton.SetParent(AParent: TWinControl);
begin
  inherited;
  if AParent <> nil then
    Caption := Name;
end;procedure Register;
begin
  RegisterComponents('Samples', [TRunButton]);
end;
  procedure TrunButton.setcaption(value:Tcaption);
    begin
      inherited;
      Fcaption:=value;
//      repaint;
    end;
  constructor TrunButton.create(Aowner:Tcomponent);
    begin
      inherited create(Aowner);
     // setcaption(Name);
      width:=45;
      height:=45;
    end;
  Function IsExecutableFile(value:TcommandLine):boolean;
    begin
      result:=(uppercase(ExtractFileExt(value))='.EXE');
    end;
  procedure Trunbutton.SetCommandLine(value:TcommandLine);
    var
    Icon:Ticon;
    begin
      if not IsExecutableFile(value) then raise exception.Create(value+'不是一个可执行文件!');
      if not FileExists(value) then raise exception.Create(value+'文件不存在!');
      FcommandLine:=value;
      Icon:=Ticon.Create;
      try
        icon.Handle:=ExtractIcon(hinstance,Pchar(FcommandLine),0);
        with Glyph do
          begin
            canvas.brush.style:=bssolid;
            canvas.FillRect(canvas.cliprect);
            width:=icon.Width;
            height:=Icon.Height;
            canvas.Draw(0,0,icon);
          end;
      finally
          icon.Free;
      end;    
    end;
  function processexecute(commandline:TcommandLine;cshow:word):integer;
    var
      rslt:longbool;
      startupinfo:Tstartupinfo;
      processinfo:Tprocessinformation;
    begin
      fillchar(startupinfo,sizeof(Tstartupinfo),#0);
      with startupinfo do
        begin
          cb:=sizeof(Tstartupinfo);
          dwflags:=startf_useshowwindow or startf_forceonfeedback;
          wshowwindow:=cshow;
        end;
      rslt:=createprocess(pchar(commandline),nil,nil,nil,false,normal_priority_class,nil,
        nil,startupinfo,processinfo);
      if rslt then
          with processinfo do
            begin
              waitforinputidle(hprocess,infinite);
              closehandle(hthread);
              closehandle(hprocess);
              result:=0;
            end
      else
            result:=getlasterror;
    end;
  procedure Trunbutton.Click;
    var
      rean:word;
    begin
      inherited click;
      rean:=ProcessExecute(FcommandLine,sw_shownormal);
      if rean<>0 then
          raise exception.Create('错误地执行了程序:'+inttostr(rean));
    end;
end.

Answer 5

解决,谢谢taxi(游少爷),lxl(蚊蚊),现在好像不能加分,等csdn好了后再加!

Answer 6

to taxi(游少爷):请问为什么在setparent中加入caption:=name才会改变caption,在其他位置比如说在create事件中为什么不行啊?setparent在什么时候触发?
奇怪问题:我在此事件最后一行中加入showmessage(name)发现在设计期时当把此控件加入form时,此事件触发两次???
而且第一次showmessage(name)是空,此时控件还在窗体的左上角,而第二次时showmessage(name)有了值,并且此时控件才移动到指定的位置,这是为什么?