How to deal with according to the different situation judgment, cancel pagecontrol tabsheet switch?

CodePudding user response:

According to different conditions to prevent tabsheet switching

CodePudding user response:

Procedure TForm1. PageControl1Changing (Sender: TObject;
Var AllowChange: Boolean);
The begin
If (your judgment conditions) then
AllowChange:=True
The else
AllowChange:=Flase;
end;

CodePudding user response:

1, set up a global variable
Var
OnChange: Boolean;


2, OnChenging eventIf onChange then
The begin
AllowChange:=True;//open
End
The else begin
AllowChange:=False;//lock
end;

3, press the button event, whether set into the pages and lock the Page

(1) PageControl1. ActivePageIndex:=1;//into the surface 2
OnChange:=False;//lock the Page

(2) the OnChange:=True;//open the Page
PageControl1. ActivePageIndex:=0;//into the surface 1


[Delphi=code]
The unit Unit1;

Interface

USES the
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls ComCtrls;

Type
TForm1=class (TForm)
PageControl1: TPageControl;
TabSheet1: TTabSheet;
TabSheet2: TTabSheet;
TabSheet3: TTabSheet;
TabSheet4: TTabSheet;
For: TButton;
Button2: TButton;
Procedure Button1Click (Sender: TObject);
Procedure PageControl1Changing (Sender: TObject;
Var AllowChange: Boolean);
Procedure Button2Click (Sender: TObject);
Private
{Private declarations}
Public
{Public declarations}
end;

Var
Form1: TForm1;
OnChange: Boolean;

Implementation

{$R *. DFM}

Procedure TForm1. Button1Click (Sender: TObject);
The begin
OnChange:=True;//open the Page
PageControl1. ActivePageIndex:=0;//into the surface 1
end;

Procedure TForm1. PageControl1Changing (Sender: TObject;
Var AllowChange: Boolean);
The begin
If onChange then
The begin
AllowChange:=True;//open
End
The else begin
AllowChange:=False;//lock
end;
end;

Procedure TForm1. Button2Click (Sender: TObject);
The begin
PageControl1. ActivePageIndex:=1;//into the surface 2
OnChange:=False;//lock the Page
end;

End.
[/code]

CodePudding user response:

 unit Unit1; 

Interface 

USES the 
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, 
Dialogs, StdCtrls ComCtrls; 

Type 
TForm1=class (TForm) 
PageControl1: TPageControl; 
TabSheet1: TTabSheet; 
TabSheet2: TTabSheet; 
TabSheet3: TTabSheet; 
TabSheet4: TTabSheet; 
For: TButton; 
Button2: TButton; 
Procedure Button1Click (Sender: TObject); 
Procedure PageControl1Changing (Sender: TObject; 
Var AllowChange: Boolean); 
Procedure Button2Click (Sender: TObject); 
Private 
{Private declarations} 
Public 
{Public declarations} 
end; 

Var 
Form1: TForm1; 
OnChange: Boolean; 

Implementation 

{$R *. DFM} 

Procedure TForm1. Button1Click (Sender: TObject); 
The begin 
OnChange:=True;//open the Page 
PageControl1. ActivePageIndex:=0;//into the surface 1 
end; 

Procedure TForm1. PageControl1Changing (Sender: TObject; 
Var AllowChange: Boolean); 
The begin 
If onChange then 
The begin 
AllowChange:=True;//open 
End 
The else begin 
AllowChange:=False;//lock 
end; 
end; 

Procedure TForm1. Button2Click (Sender: TObject); 
The begin 
PageControl1. ActivePageIndex:=1;//into the surface 2 
OnChange:=False;//lock the Page 
end; 

End.