Sendkeys

[yamahaCal]

I need to know how I can have my VB application wait until something is open after a shell line before the SendKeys line activates.

thanks.

[jemidiah]

Different applications load differently. There is no 'finished loading' flag, meaning the best way to do what you want is to simply wait a specified amount of time before the SendKeys statement.

[Joacim Andersson]

You can use the WaitForInputIdle function to get information when a process is ready to get input from the mouse or keyboard. However this function requires a hProcess handle which you don't get from the VB Shell function. You must eighter use CreateProcess or the ShellExecuteEx function.

I've written a wrapper sub that uses ShellExecuteEx to launch a file and then waits for the process to be ready to get input from the keyboard before it returns.

Private Declare Function ShellExecuteEx Lib "shell32.dll" (ByRef lpExecInfo As SHELLEXECUTEINFO) As Long
Private Declare Function WaitForInputIdle Lib "user32" (ByVal hProcess As Long, ByVal dwMilliseconds As Long) As Long
Private Declare Function CloseHandle Lib "kernel32" (ByVal hObject As Long) As Long
 
Private Type SHELLEXECUTEINFO
    cbSize As Long
    fMask As Long
    hwnd As Long
    lpVerb As String
    lpFile As String
    lpParameters As String
    lpDirectory As String
    nShow As Long
    hInstApp As Long
    ' fields
    lpIDList As Long
    lpClass As Long
    hkeyClass As Long
    dwHotKey As Long
    hIcon As Long
    hProcess As Long
End Type
 
Private Const SEE_MASK_NOCLOSEPROCESS = &H40
Private Const SEE_MASK_FLAG_NO_UI = &H400
 
Public Sub ShellAndWaitForReady(ByVal sFile As String)
    Dim hProcess As Long
    Dim shi As SHELLEXECUTEINFO
    Dim nRet As Long
    
    shi.lpDirectory = vbNullString
    shi.lpVerb = "Open"
    shi.lpParameters = vbNullString
    shi.lpFile = sFile
    shi.nShow = vbNormalFocus
    shi.fMask = SEE_MASK_FLAG_NO_UI Or SEE_MASK_NOCLOSEPROCESS
    shi.cbSize = Len(shi)
    
    If ShellExecuteEx(shi) > 32 Then
        hProcess = shi.hProcess
        Do
            nRet = WaitForInputIdle(hProcess, 500)
            DoEvents
        Loop While nRet <> 0
        CloseHandle hProcess
    End If
End Sub

Just call ShellAndWaitForReady and pass it the file to launch (this could be either a program or a document that has an associated program).

Best regards

[jemidiah]

That's a really cool API, although it is very application specific. Better than my solution, though

[Joacim Andersson]

Originally posted by jemidiah
That's a really cool API, although it is very application specific. Better than my solution, though

Application specific? Yes, it only works on Windows application and of course all application might not react to keyboard input even though it's ready to do so... but to that kind of application you can't use SendKeys anyway.

[jemidiah]

I tried it on Acrobat Reader 6, and it returned during the splash screen, which is why I said app. specific (mostly I was trying to insinuate they should, of course, test it on each app. they intended to use it on)