OpenEuphoria

1. Combo Box Odd Display Behavior

• Posted by wynco Nov 12, 2011
• 2100 views

I'm getting an odd display behavior in my combo boxes since switching to EU4. If the drop down list has more than 30 items then the empty space to right of the list's items has a black background instead white. As I mouse over the list the black disapears as the pointer moves over each item. Also any movement of the right scroll bar clears all the black. I'm using w32lib v0.70.18 and Vista Home Premium SP2.

Below is a sample program the demonstrates the effect on my system.

include Win32lib.ew 
constant MainWindow = createEx(Window, "Combo Box Bug Test", 0, 100, 100, 440, 100, 0, 0) 
	constant ComboOne = createEx(Combo, "", MainWindow, 8, 10, 200, 0, 0, 0) 
		for x = 1 to 30 do 
			addItem(ComboOne, "Combo One")			 
		end for 
		setIndex(ComboOne, 1) 
	constant ComboTwo = createEx(Combo, "", MainWindow, 220, 10, 200, 0, 0, 0) 
		for x = 1 to 31 do 
			addItem(ComboTwo, "Combo Two")			 
		end for 
		setIndex(ComboTwo, 1) 
WinMain(MainWindow,Normal)

3. Re: Combo Box Odd Display Behavior

• Posted by DerekParnell (admin) Nov 13, 2011
• 2023 views

These is a known problem with Win32lib combos and tabs when using Vista or Windows 7. It has nothing to do with Eu4. It's on the list of repairs that I have to fix in the library.

5. Re: Combo Box Odd Display Behavior

• Posted by wynco Nov 13, 2011
• 1974 views

I ran the changes you suggested and found I am actually using win32lib v0.70.20 13-Nov-2010. I cannot find a newer version. When I try to download the latest version the file I find has the same version number and date.

7. Re: Combo Box Odd Display Behavior

• Posted by mattlewis (admin) Nov 14, 2011
• 1872 views

I'm seeing it on XP. I suspect this is related to the manifest issue. I'm running the head of svn, which reports "v0.70.20 13-Nov-2010" as its version. Here's what I see:

• Inside each combobox, below the text, there is a black line.
• When I open the drop downs:
  • The left box (30 items) has a white background, as expected.
  • The right box (31) items has a black background. It has more items than are displayed, and there is a scroll bar. When I scroll the list, the background goes back to white. If I open the drop down later, it is black again.

Derek, it may be a difference in how many items are required to scroll (or a difference with XP and 7).

Matt

9. Re: Combo Box Odd Display Behavior

• Posted by DerekParnell (admin) Nov 14, 2011
• 1885 views

That's the issue I now have to face, because I do NOT have the problem, and I am using "a euphoria / win32 lib / windows combination". So how to I fix something that I can't see is broken? It works perfectly correct on my system. Why? I don't have a clue.

Can anyone point me in some direction for help?

11. Re: Combo Box Odd Display Behavior

• Posted by mattlewis (admin) Nov 14, 2011
• 1930 views

Since the problem is with backgrounds, it may have to do with something like a WM_ERASEBACKGROUND message. Or maybe something to do with Custom Drawing messages?

Matt

13. Re: Combo Box Odd Display Behavior

• Posted by m_sabal Jun 22, 2012
• 1614 views

Yes this is an old thread, but it is still a current issue. I've spent way too much time trying to hunt it down, and have to call it quits for now and either move back to Euphoria 3/Win32 0.6 or jump to Java (eww). Here's what I know:
- In Vista and beyond, Microsoft changed the way ListBox, DropDownList, and ComboBox(Ex) were handled.
- The upgrade to Win32 0.7 took care of making the controls work correctly in the newer operating systems.
- At the same time, Win32 0.7 was written to allow it to work with Euphoria 4.
- In fDoColor, any control that wasn't directly created by Win32Lib gets no treatment.
- The dropdown portion of the control has a different Windows handle than the edit portion, so when a setBackground is issued on the combo, only the edit portion is affected.

Possible fixes:
- Declare Windows XP/2003 as unsupported with Win32 0.7. (Have to go back to Eu 3 + Win32 0.6, or use a different GUI toolkit.)
- Change the way ComboBoxes are styled in CreateEx, so that they are not user drawn. This removes the ability to add colors, images, and fonts.
- Find a way to get the parent of the wParam since wParam will have no reference in the sequences managed by win32lib, check if the parent is a dropdownlist or combobox, and apply the parent's font/color/background to the dropdown portion.

At this point I'm out of time and am reverting to Eu3 since too many of my users and servers are still on WinXP/2003.

15. Re: Combo Box Odd Display Behavior

• Posted by mattlewis (admin) Jun 25, 2012
• 1457 views

I posted one way to fix this issue here:

http://openeuphoria.org/forum/m/117380.wc

This was what I said:

    return {kMainMsg , -1} 

 
	if not equal( classBGColor[ctrl_Type[lControl]], w32BGTransparent ) and 
	not equal(ctrl_Bg_Color[lControl], w32WinDefColor) then 

include win32lib.ew  
constant Win1 = create(Window,"Strange",0,Default,Default,400,400,0),  
		TabCtl = create(TabControl,"",Win1,5,5,380,355,0),  
		Tab1 = create(TabItem,"First",TabCtl,0,0,0,0,0),  
		Label1 = create(CText,"Nothing important",Tab1,10,30,360,25,0),  
		Cbox1 = create(Combo,"",Tab1,20,80,250,100,0)  
WinMain(Win1,Normal)  

Matt