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Speedy List Boxes

Speedy List Boxes

One way to speed list-box loading is to eliminate the constant redrawingrequired while loading. You can do this by calling the LockWindowUpdateAPI. LockWindowUpdate accepts an HWND as a parameter to start the lockand a zero parameter to unlock it. Only one window can be locked at a time.If LockWIndowUpdate is called with another HWND, the currently locked windowwill be unlocked. To run this sample, put a command button and a list box on a form andpaste in this code. Your code may not require the DoEvents within the loopthat adds items, and a tight basic loop will keep the list from updating.However, there are times when the DoEvents is required.

 Private Declare Function LockWindowUpdate Lib "user32" (ByVal hwndLock As Long) As LongPrivate Sub Command1_Click()	Dim i%	LockWindowUpdate (List1.hWnd)	For i% = 1 To 1000		List1.AddItem Str$(i%)		DoEvents	Next	LockWindowUpdate (0&)End Sub

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