The MaxGUI Beginner Tutorial Series - Tutorial 10:  ComboBoxes
(c) Assari Dec 26 2005

In this tutorial we are going to look at ComboBoxes, a very similar gadget to Listboxes, which we had covered rather extensively in the three previous tutorials.

Lets take a look at a simple ComboBox:-

SuperStrict Local MyWindow:TGadget=CreateWindow("ComboBox Example", 200,200,320,240) Local ComboBox:TGadget=CreateComboBox(10,10,200,100,MyWindow) AddGadgetItem  ComboBox,"First Item" AddGadgetItem  ComboBox,"Second Item" Repeat   WaitEvent()   Select EventID()   Case EVENT_WINDOWCLOSE      End    End Select Forever

ComboBoxes requires the user to click on the downarrow button to activate the drop down.
 This is of course cheaper on screen real estate.


We can also set a default item as follows:-

SuperStrict Local MyWindow:TGadget=CreateWindow("ComboBox Example", 200,200,320,240) Local ComboBox:TGadget=CreateComboBox(10,10,200,100,MyWindow) AddGadgetItem  ComboBox,"First Item" AddGadgetItem  ComboBox,"Second Item" SelectGadgetItem  ComboBox,1 Repeat   WaitEvent()   Select EventID()   Case EVENT_WINDOWCLOSE      End    End Select Forever

As we can see from the picture below, the Second Item text appears in the ComboBox ready to be selected.


Just like ListBoxes, we can use the SelectedGadgetItem to retrieve the index and GadgetItemText to retrieve the element itself. Let us see an example of these functions in action

SuperStrict Local MyWindow:TGadget=CreateWindow("ComboBox Example", 200,200,320,240) Local ComboBox:TGadget=CreateComboBox(10,10,200,100,MyWindow) For Local i:Int=1000 To 1050   AddGadgetItem ComboBox,i Next Local s:String Repeat   WaitEvent()   Select EventID()   Case EVENT_WINDOWCLOSE      End   Case EVENT_GADGETACTION      s=GadgetItemText(ComboBox,SelectedGadgetItem(ComboBox))      SetStatusText MyWindow, "index="SelectedGadgetItem(ComboBox) + ":item=" + s    End Select Forever

As we can see below, the selected item is displayed by the above SetStatusText function on the status bar. Note that the above program is very similar to an earlier example in Tutorial 8 using listboxes instead of comboboxes. A lot of the functions which apply to Listboxes also apply to Comboboxes as well.



Summary

This has been a short tutorial, simply because we have covered all the functions that can be used to manipulate a combobox in the previous listbox tutorials.

To recap what we have learnt so far

• ComboBoxes can be created using the CreateComboBox function 
• Gadget functions used for listboxes also works in similar manner for ComboBoxes
• Icons can also be added to items using the LoadIconStrip and SetGadgetIconStrip functions similar to listboxes.
  

So thats ends our tutorial for now. Back to Tutorial Index.