Delphi – How to make a component disappear in the form designer

componentsdelphidesign-timevisibility

I'm creating a custom control that contains other controls, including two scroll bars, one horizontal, one vertical. There's a property to set one or both scroll bars invisible, which works fine at runtime, but at design-time it doesn't disappear from the form designer when I set the property.

Now, I can understand how this could be a useful feature if this was an individual control, but it's part of an aggregate component and so it ought to obey the parent control's rules, not the form designer's. Is there any way to make sure the control will disappear when I set .Visible := false; even when it's in the form designer?

Best Answer

You can set the "csNoDesignVisible" ControlStyle flag of the control. If that flag is set the Visible property will work as it does at runtime.

Related Solutions

C# – Custom Designer class for a .NET Windows Form issue

Well, the LoadComplete event is the correct point. I usually check the Loading property to check if the Initialize is happening while loading or it has been called after the load.

IDesignerHost _host;
Form _form;

public override void Initialize(System.ComponentModel.IComponent component)
{
  _form = component as Form;
  _host = (IDesignerHost)this.GetService(typeof(IDesignerHost));
  if (_host != null)
  {      
   if (_host.Loading)
   {
     _host.LoadComplete += new EventHandler(_host_LoadComplete);
   }
   else
   {
     initializeForm();
   }
  }
}

void _host_LoadComplete(object sender, EventArgs e)
{
  _host.LoadComplete -= new EventHandler(_host_LoadComplete);
  initializeForm();
}

void initializeForm()
{
   if (_form!= null)
   {
      ...
   }
}

Another approach is to create a Component that you can drop into a form and create a designer for the component instead of recreating the FormDesigner. From the component designer you can get the parent form using the _host.RootComponent property.

Delphi – How to make the scroll bars show up on a TScrollBox

Set AutoScroll property to True.
Now if you add controls that clip the box borders, the bars will appear.

Best Answer

Related Solutions

C# – Custom Designer class for a .NET Windows Form issue

Delphi – How to make the scroll bars show up on a TScrollBox

Related Topic