在 Inno Setup 中更改 ComboBox 后，在下一个屏幕上动态显示控件和内容？

Question

当我运行第一次使用此代码时，一切都按预期进行。但是一旦你 select Sonitor 然后 select BBraun, Sonitor 控件（标签和文本框）不会消失，它们仍然在屏幕上。

[Code]
var
  VendorPage, VendorHostPage: TWizardPage;
  VendorText: TNewStaticText;
  VendorEdit: TNewEdit;
  ComboBox: TNewComboBox;
  
procedure ComboBoxChange(Sender: TObject);
begin
  case ComboBox.ItemIndex of
    0:
    begin
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'AssetTracking connects to the BBraun server to recieve the HL7 data';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(25);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'BBraun HL7 port:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(25);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface; 
      
    end;
    1:
    begin
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'AssetTracking connects to RTLS server to recieve streaming location data';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(25);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'Centrak RTLS Server IP address:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(25);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface;
      
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(50);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'Centrak RTLS Server port:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(50);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface;      
    end;
    2:
    begin
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'AssetTracking connects to RTLS server to recieve streaming location data';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(25);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'Sonitor RTLS Server IP address:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(25);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface;
      
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(50);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'Sonitor RTLS Events port:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(50);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface;   
           
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(75);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'Sonitor RTLS API port:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(75);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface; 
    end;
  end;
end;

procedure InitializeWizard;
var
  InstallJava: Boolean;
  
begin
  VendorPage := CreateCustomPage(wpWelcome, 'RTLS HW Data Source Configuration', '');
  
  VendorText := TNewStaticText.Create(VendorPage);
  VendorText.Anchors := [akLeft, akRight, akBottom];
  VendorText.Caption := 'Please select the RTLS hardware vendor to install:';
  VendorText.AutoSize := True;
  VendorText.Parent := VendorPage.Surface;

  VendorText := TNewStaticText.Create(VendorPage);
  VendorText.Top := ScaleY(25);
  VendorText.Anchors := [akLeft, akRight, akBottom];
  VendorText.Caption := 'RTLS Vendor';
  VendorText.AutoSize := True;
  VendorText.Parent := VendorPage.Surface;

  ComboBox := TNewComboBox.Create(VendorPage);
  ComboBox.Top := ScaleY(25);
  ComboBox.Left := ScaleX(100);
  ComboBox.Anchors := [akLeft, akTop, akRight];
  ComboBox.Parent := VendorPage.Surface;
  ComboBox.Style := csDropDown;
  ComboBox.Items.Add('BBraun');
  ComboBox.Items.Add('Centrak');
  ComboBox.Items.Add('Sonitor');
  ComboBox.ItemIndex := 0;
  ComboBox.OnChange := @ComboBoxChange;

  VendorHostPage := CreateCustomPage(VendorPage.ID, 'RTLS HW Data Source Configuration', 'Provide Connection details to Teletracking RTLS');
  
  case ComboBox.ItemIndex of
    0:
    begin
      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'AssetTracking connects to the BBraun server to recieve the HL7 data';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorText := TNewStaticText.Create(VendorHostPage);
      VendorText.Top := ScaleY(25);
      VendorText.Anchors := [akLeft, akRight, akBottom];
      VendorText.Caption := 'BBraun HL7 port:';
      VendorText.AutoSize := True;
      VendorText.Parent := VendorHostPage.Surface;

      VendorEdit := TNewEdit.Create(VendorHostPage);
      VendorEdit.Top := ScaleY(25);
      VendorEdit.Left := ScaleX(200);
      VendorEdit.Parent := VendorHostPage.Surface; 
    end;
  end;
 
end;

select离子组合框值后的预期行为：

PS：如果您在浏览器上看不到图像，请下载它，代码已经为前两个屏幕 ComboBox 和下一个屏幕编写了基于 selection not剩下的。

Answer 1

当然不是。在 Pascal 脚本中分配一个 object 变量不会破坏该变量先前指向的 object。

你必须明确地这样做。喜欢：

if Assigned(VendorText) then VendorText.Free;

虽然更常见的实现方式，但您想要的是在开始时创建一次控件，hiding/showing and/or 随着组合框选择的变化改变它们的标题。这样的解决方案需要的代码要少得多。

在 Inno Setup 中更改 ComboBox 后，在下一个屏幕上动态显示控件和内容？

Dynamically show the control and content on next screen after ComboBox change in Inno Setup?

inno-setup

pascalscript