GUI.SetDisplayWhenCreated

OpenTuring

GUI.SetDisplayWhenCreatedPart of GUI module

Syntax   GUI.SetDisplayWhenCreated (display : boolean)

Description   By default, whenever a widget is created with a GUI.Create… procedure, the widget instantly appears. Sometimes, this is not the desired behaviour. For example, if several widgets are to occupy the same location with only one being displayed at a time, then it is desirable not to have the widget appear when first created.

If a widget is not displayed when created, then GUI.Show must be called to make the widget visible.

If the display parameter is true, then widgets are displayed immediately upon creation. If the display parameter is set to false, then the widget is not made visible on creation and GUI.Show must be called to display the widget.

Example   The following program toggles the visiblility of the frame when the button is pushed. The frame starts out invisible.

        import GUI in "%oot/lib/GUI" 
        View.Set ("graphics:150;100") 
        
        var visible : boolean := false
        var button, frame : int
        
        procedure Toggle
            if visible then
                GUI.Hide (frame)
            else
                GUI.Show (frame)
            end if
            visible := not visible
        end Toggle
        
        button := GUI.CreateButton (25, 40, 0, "Toggle Frame", Toggle)
        GUI.SetDisplayWhenCreated (false)
        frame := GUI.CreateFrame (10, 10, 140, 90, 0)
        
        loop
            exit when GUI.ProcessEvent
        end loop

Status   Exported qualified.

This means that you can only call the function by calling GUI.SetDisplayWhenCreated, not by calling SetDisplayWhenCreated.