delphi - SmartTabs 运行时事件错误

Question

这是我收到错误的代码部分:

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, cefvcl, Vcl.ExtCtrls, Vcl.StdCtrls, ceflib,
  Vcl.ComCtrls, Vcl.ImgList, Vcl.Imaging.pngimage, Vcl.Buttons, JvSpeedButton, Themes,
  JvExComCtrls, JvComCtrls, JvgPage, Vcl.ToolWin, JvToolBar, Vcl.Menus,
  Vcl.Mask, JvExMask, JvToolEdit, JvExButtons, JvButtons, rkSmartTabs, rkAeroTabs;

type
  TForm1 = class(TForm)
    {....}
    procedure FormCreate(Sender: TObject);
    procedure addnewtab (Sender: TObject);
    procedure closetab (Sender: TObject);

private
  { Private declarations }
public
  { Public declarations }
end;

var
  Form1: TForm1;


implementation

{$R *.dfm}

{....}

procedure TForm1.closetab (Sender: TObject);
var
  smarttabs: TrkAeroTabs;
begin
  smarttabs := Sender as TrkAeroTabs;
  smarttabs.DeleteTab(smarttabs.ActiveTab);
end;

procedure TForm1.addnewtab (Sender: TObject);
var
  smarttabs: TrkAeroTabs;
begin
  smarttabs := Sender as TrkAeroTabs;
  smarttabs.AddTab('New Tab');
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
with TrkAeroTabs.Create(self) do
  begin
    OnCloseTab := closetab;  //***ERROR HERE***
    OnAddClick := addnewtab;
    Parent := Self;
    Align := alClient;
    AddTab('New Tab');
    if ClassType = TrkAeroTabs then
    begin
      ColorBackground := clBlack;
      with Self do
      begin
        GlassFrame.Top     := 25;
        GlassFrame.Enabled := True;
      end;
    end;
    ShowButton   := True;
    AllowTabDrag := True;
  end;
end;

这是错误:

[DCC Error] Unit1.pas(90): E2009 Incompatible types: 'Parameter lists differ'

addnewtab() 工作正常。我不明白为什么 closetab() 不起作用。谢谢。

Answer 1

它不起作用，因为该事件是使用与 TNotifyEvent 不同的类型声明的，并且您的方法参数必须与所使用的类型中声明的内容匹配(参数的数量和类型)。

导航到事件声明，您会发现:

  TrkAeroTabs = class(TCustomControl)
  ..
  published
  ..
    property OnCloseTab: TOnTabCloseEvent read FOnCloseTab write FOnCloseTab;

然后，导航到 TOnTabClos​​eEvent 声明，您会发现:

TOnTabCloseEvent = procedure(Sender: TObject; Index: Integer;
  var Close: Boolean) of object;

所以，你必须像这样声明你的方法:

  TForm1 = class(TForm)
    ..
    procedure closetab (Sender: TObject; Index: Integer; var CanClose: Boolean);


procedure TForm1.closetab (Sender: TObject; Index: Integer; var CanClose: Boolean);
var
  smarttabs: TrkAeroTabs;
begin
  smarttabs := Sender as TrkAeroTabs;
  smarttabs.DeleteTab(smarttabs.ActiveTab);
end;

现在，您可以成功将此方法分配给事件。