c++ - 自定义消息Dlg

Question

我正在尝试在 borland c++ builder 中制作自定义 messagedlg。但是下面的代码不是更改按钮标题，而是在对话框窗体的左上角创建新按钮。

#include <vcl.h>
#pragma hdrstop

#include "frmMsgDlg.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
    : TForm(Owner)
{
}
int __fastcall MsgDlg( const String Msg, TMsgDlgType DlgType, TMsgDlgButtons Buttons, const String* Captions, int Captions_maxidx )
{
  int m = 0;
  TButton *DlgButton;
  int CaptionIndex = 0;
  TForm* aMsgDlg = CreateMessageDialog( Msg, DlgType, Buttons );
  aMsgDlg->Color = TColor(clWindow);

  for ( m = 0; m <= aMsgDlg->ComponentCount - 1; m++)
  {
    if ( dynamic_cast< TButton *>( aMsgDlg->Components[m] ) )
    {
      DlgButton = new TButton( aMsgDlg->Components[m] );
      DlgButton->Parent = aMsgDlg;
      if ( CaptionIndex > Captions_maxidx /*# High(Captions) */ ) break;

      DlgButton->WordWrap = true;
      DlgButton->Caption = Captions[CaptionIndex];
      DlgButton->Width = 56;
      DlgButton->Height= 28;
      DlgButton->Cancel = false;
      CaptionIndex++;
    }
  }
  return aMsgDlg->ShowModal();

}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormShow(TObject *Sender)
{
  int msg;
  String capt[2] = {"PO","JO"};

  msg = MsgDlg("Tre tentime dështuan, ju lutem startoni programin nga ikona!!!", mtInformation,TMsgDlgButtons() << mbOK <<mbCancel,capt,2);

}
//---------------------------------------------------------------------------

Answer 1

它创建新按钮，因为它实际上是在创建新按钮，在行中:

DlgButton = new TButton( aMsgDlg->Components[m] );

您设置了 Width 和 Height，但没有设置 Top 或 Left 属性，因此它们将是默认情况下设置为 0 - 即父组件的左上角。

如果您尝试更改现有按钮的标题，而不是制作新按钮，只需将组件转换为按钮(您刚刚检查过，您可以在 if 语句，因为 dynamic_cast 执行运行时检查以查看类是否相关，如果不能安全地转换则返回 NULL)并改为修改它，如下所示:

if (dynamic_cast<TButton*>(aMsgDlg->Components[m])) {
   DlgButton = dynamic_cast<TButton*>(aMsgDlg->Components[m]) // <- this is the key difference
   if (CaptionIndex > Captions_maxidx /*# High(Captions) */) break;
   DlgButton->WordWrap = true;
   DlgButton->Caption = Captions[CaptionIndex];
}

这将允许您修改现有按钮而不是创建新按钮。