[Done] ComboBox content list size after ClearGadgetItems()

[boddhi]

Hello,
 

Code: Select all

If OpenWindow(0, 0, 0, 270, 188, "ComboBoxGadget", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
  ComboBoxGadget(0, 10, 10, 250, 21, #PB_ComboBox_Editable)
  TextGadget(#PB_Any,10,40,250,22,"1. Show ComboBox items")
  TextGadget(#PB_Any,10,62,250,22,"2. Click button")
  TextGadget(#PB_Any,10,84,250,22,"3. Show ComboBox items")
  TextGadget(#PB_Any,10,106,250,22,"4. Click button")
  TextGadget(#PB_Any,10,128,250,22,"5. Show ComboBox content size")
  ButtonGadget(1,10,154,250,22,"Populate ComboBox")
  Repeat 
    Select WaitWindowEvent()
      Case #PB_Event_CloseWindow
        exit=#True
      Case #PB_Event_Gadget
        Select EventGadget()
          Case 1
            Select GetGadgetData(1)
              Case #False
                AddGadgetItem(0,-1,"Item 1")
                AddGadgetItem(0,-1,"Item 2")
                AddGadgetItem(0,-1,"Item 3")
                AddGadgetItem(0,-1,"Item 4")
                SetGadgetData(1,#True)
                SetGadgetText(1,"Clear ComboxBox content")
              Case #True
                SetGadgetData(1,#False)
                SetGadgetState(0,-1)
                ClearGadgetItems(0)
                SetGadgetText(1,"Populate ComboBox")
            EndSelect
        EndSelect
    EndSelect
  Until exit=#True
EndIf

 
Why doesn't the content list size reset after a ClearGadgetItems()?
 
Thanks.

Win10 x64 / PB 6.11 x64

[BarryG]

Correct; the drop-down list size stays the last height from the items. Maybe a bug, maybe not.

If it bothers you, you can always just redo the gadget since it holds no data anyway:

Code: Select all

Procedure DoComboBox()
  ComboBoxGadget(0, 10, 10, 250, 21, #PB_ComboBox_Editable)
EndProcedure

If OpenWindow(0, 0, 0, 270, 188, "ComboBoxGadget", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
  DoComboBox()
  TextGadget(#PB_Any,10,40,250,22,"1. Show ComboBox items")
  TextGadget(#PB_Any,10,62,250,22,"2. Click button")
  TextGadget(#PB_Any,10,84,250,22,"3. Show ComboBox items")
  TextGadget(#PB_Any,10,106,250,22,"4. Click button")
  TextGadget(#PB_Any,10,128,250,22,"5. Show ComboBox content size")
  ButtonGadget(1,10,154,250,22,"Populate ComboBox")
  Repeat 
    Select WaitWindowEvent()
      Case #PB_Event_CloseWindow
        exit=#True
      Case #PB_Event_Gadget
        Select EventGadget()
          Case 1
            Select GetGadgetData(1)
              Case #False
                AddGadgetItem(0,-1,"Item 1")
                AddGadgetItem(0,-1,"Item 2")
                AddGadgetItem(0,-1,"Item 3")
                AddGadgetItem(0,-1,"Item 4")
                SetGadgetData(1,#True)
                SetGadgetText(1,"Clear ComboxBox content")
              Case #True
                DoComboBox()
                SetGadgetData(1,#False)
                SetGadgetText(1,"Populate ComboBox")
            EndSelect
        EndSelect
    EndSelect
  Until exit=#True
EndIf

[RASHAD]

Code: Select all

              Case #True 
                For i = 0 To CountGadgetItems(0)
                  RemoveGadgetItem(0,0)
                Next
                SetGadgetItemText(0,0,"")                
                SetGadgetText(1,"Populate ComboBox")

[boddhi]

Hi BarryG & Rashad,

Thank you for your replies.

If it bothers you, you can always just redo the gadget since it holds no data anyway:

...and your suggestion to delete and recreate the gadget.

However, it's going to be more complicated because I'm using the Dialog library which does not allow to do this simply, except at the cost of container nesting .

For [...] : RemoveGadgetItem(0,0) : Next

I used ClearGadgetItems() in my example for a simple demonstration.
I'm already using RemoveGadgetItem() because I don't necessarily have to delete all the items in the list.
But when I delete the last item, the list size is not reset to 0 and "retains memory” of the number of items it has contained.

[BarryG]

You won't believe this, but ChatGPT indirectly told me a hacky way to do it.

This is what I asked: "using purebasic, how do i clear a comboboxgadget so that its drop down list is one item high".

Its answer was (bolded by me to the clue):

In PureBasic, you can clear a ComboBoxGadget by removing all the items from it. To make the drop-down list appear with only one item height, you would typically want to remove all items except one.

One item, you say? Okay, so let's do it:

Code: Select all

If OpenWindow(0, 0, 0, 270, 188, "ComboBoxGadget", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
  ComboBoxGadget(0, 10, 10, 250, 21, #PB_ComboBox_Editable)
  TextGadget(#PB_Any,10,40,250,22,"1. Show ComboBox items")
  TextGadget(#PB_Any,10,62,250,22,"2. Click button")
  TextGadget(#PB_Any,10,84,250,22,"3. Show ComboBox items")
  TextGadget(#PB_Any,10,106,250,22,"4. Click button")
  TextGadget(#PB_Any,10,128,250,22,"5. Show ComboBox content size")
  ButtonGadget(1,10,154,250,22,"Populate ComboBox")
  Repeat 
    Select WaitWindowEvent()
      Case #PB_Event_CloseWindow
        exit=#True
      Case #PB_Event_Gadget
        Select EventGadget()
          Case 1
            Select GetGadgetData(1)
              Case #False
                AddGadgetItem(0,-1,"Item 1")
                AddGadgetItem(0,-1,"Item 2")
                AddGadgetItem(0,-1,"Item 3")
                AddGadgetItem(0,-1,"Item 4")
                SetGadgetData(1,#True)
                SetGadgetText(1,"Clear ComboxBox content")
              Case #True
                SetGadgetData(1,#False)
                ;
                ; These 3 lines thanks to ChatGPT.
                ClearGadgetItems(0)
                AddGadgetItem(0,-1,"")
                ClearGadgetItems(0)
                ;
                SetGadgetText(1,"Populate ComboBox")
            EndSelect
        EndSelect
    EndSelect
  Until exit=#True
EndIf

It's clear that ChatGPT does have its uses.

[boddhi]

In PureBasic, you can clear a ComboBoxGadget by removing all the items from it. To make the drop-down list appear with only one item height, you would typically want to remove all items except one.

Thanks to you (and ChatGPT ) for your research

In fact, it has the same result as Rashad's code: A height of an item. There seems to be a constraint here .

Note : However, a worth difference in gadget initialization between using the Dialog library and the classic Gadget library
With Gadget library:

 
With Dialog library:

[BarryG]

Post your snippet for the Dialog version so I can test?

[boddhi]

Post your snippet for the Dialog version so I can test?

 

Code: Select all

ChaineXML.s="<?xml version='1.0' encoding='UTF-16'?>"+Chr(10)+ ;{
            "<dialogs>"+Chr(10)+
            "  <window id='0' name='RF_FENPRINCIPALE' text='Test' xpos='0' ypos='0' width='400' height='auto' minwidth='auto' minheight='auto' maxheight='auto' margin='10' flags='#PB_Window_SystemMenu|#PB_Window_MinimizeGadget|#PB_Window_SizeGadget|#PB_Window_ScreenCentered|#PB_Window_WindowCentered'>"+Chr(10)+
            "    <vbox expand='yes' align='' spacing='2'>"+Chr(10)+
            "      <combobox id='0' name='GAD_FP_LS_ACTION' height='24' flags='#PB_ComboBox_Editable'/> "+Chr(10)+
            "      <empty height='8'/>"+Chr(10)+
            "    </vbox> "+Chr(10)+
            "  </window>"+Chr(10)+
            "</dialogs>" ;}

If ParseXML(0,ChaineXML)
  If XMLStatus(0)=#PB_XML_Success
    If CreateDialog(0)
      NoDialogue=OpenXMLDialog(0,0,"RF_FENPRINCIPALE")
      If NoDialogue
        Repeat
        Until WaitWindowEvent()=#PB_Event_CloseWindow
        FreeDialog(0)
      EndIf
    EndIf
    FreeXML(0)
  EndIf
EndIf

[BarryG]

Sorry, I thought you'd post a Dialog version of the code above for testing. I haven't used the Dialog lib before so don't have time to work this out from scratch. I was just going to tinker with a Dialog version that matched the above.

[AZJIO]

Code: Select all

If OpenWindow(0, 0, 0, 270, 188, "ComboBoxGadget", #PB_Window_SystemMenu | #PB_Window_ScreenCentered)
	ComboBoxGadget(0, 10, 10, 250, 21, #PB_ComboBox_Editable)
	ButtonGadget(1, 10, 124, 120, 22, "Add")
	ButtonGadget(2, 140, 124, 120, 22, "Clear")
	TextGadget(3,10,150,260,38,"Click 'Add'")
	Repeat
		Select WaitWindowEvent()
			Case #PB_Event_CloseWindow
				exit = #True
			Case #PB_Event_Gadget
				Select EventGadget()
					Case 1
						For i = 0 To 3
							AddGadgetItem(0,  - 1, "Item " + Str(i))
						Next
						SendMessage_(GadgetID(0),#CB_SHOWDROPDOWN,1,1)
						Delay(330)
						SendMessage_(GadgetID(0),#CB_SHOWDROPDOWN,0,1)
						SetGadgetText(3, "Click 'Clear'")
					Case 2
						SendMessage_(GadgetID(0), #CB_SETMINVISIBLE, 1, 0)
						SetGadgetState(0,  - 1)
						ClearGadgetItems(0)
; 						For i = CountGadgetItems(0) - 1 To 0 Step  -1
; 							RemoveGadgetItem(0,i)
; 						Next
; 						For i = 0 To CountGadgetItems(0) - 1
; 							RemoveGadgetItem(0,0)
; 						Next
; 						SendMessage_(GadgetID(0), #CB_INITSTORAGE, 22, 88)
; 						SendMessage_(GadgetID(0), #CB_RESETCONTENT, 0, 0)
; 						SendMessage_(GadgetID(0), #CB_SETDROPPEDWIDTH, 400, 0)
						SendMessage_(GadgetID(0), #CB_SETMINVISIBLE, 30, 0)
						SendMessage_(GadgetID(0),#CB_SHOWDROPDOWN,1,1)
						SetGadgetText(3, "Did you understand anything? Count=" + CountGadgetItems(0))
				EndSelect
		EndSelect
	Until exit = #True
EndIf

[Fred]

Fixed.

[boddhi]

@AZJIO
As your last post has no message, I don't know whether it's intended for me or not, and what to make of your code having, in the end, the same result as those proposed before.

So, to answer the question asked when I ran your code: No, I haven't understood anything!

Fixed.

Thanks. Merci.