TabControlChange (Delphi)

Description

This example uses a tab control to display the contents of several files. To run the example, place a tab control on a form and add a memo control that fits into its client area. Be sure to leave enough room for the tabs when they appear. Then add an OpenDialog and a button to the form. The "Add a file" button adds a single file to the tab control. The "Assign files" button removes previous files and can be used to assign multiple files. To assign multiple files, press CTRL+Select or SHIFT+Select to select files in the OpenDialog.

Code

procedure TForm1.Add_a_fileClick(Sender: TObject);
var index : integer;
begin
  OpenDialog1.Options :=
    [ofAllowMultiSelect, ofFileMustExist, ofHideReadOnly];
  if OpenDialog1.Execute then
  begin
    index:= TabControl1.Tabs.Add(OpenDialog1.FileName);
    Memo1.Lines.LoadFromFile(TabControl1.Tabs[index]);
    TabControl1Change(Sender);
  end;
end;

procedure TForm1.Assign_filesClick(Sender: TObject);
var index : integer;
begin
  OpenDialog1.Options :=
    [ofAllowMultiSelect, ofFileMustExist, ofHideReadOnly];
  if OpenDialog1.Execute then
  begin
    TabControl1.Tabs.Assign(OpenDialog1.Files);
    Memo1.Lines.LoadFromFile(
      TabControl1.Tabs[TabControl1.TabIndex]);
  end;
end;

{
Place the following code in the tab control's OnChange event
handler.
procedure TForm1.TabControl1Change(Sender: TObject);
begin
  with TabControl1 do
    Memo1.Lines.LoadFromFile(Tabs[TabIndex]);
end;

Uses

• Vcl.ComCtrls.TCustomTabControl.Tabs ( fr | de | ja )
• Vcl.ComCtrls.TCustomTabControl.TabIndex ( fr | de | ja )
• Vcl.ComCtrls.TCustomTabControl.OnChange ( fr | de | ja )
• System.Classes.TStrings.Assign ( fr | de | ja )
• System.Classes.TStrings.Add ( fr | de | ja )
• Vcl.Dialogs.TOpenDialog.FileName ( fr | de | ja )
• Vcl.Dialogs.TOpenDialog.Files ( fr | de | ja )