Source code for Drag and Drop files in listbox.

[bulamb0d]

copy all text below and save with .g32 to test it.



// Demonstrates the use of the Drag and Drop

// functions located in Shell32. It will

// not accept folder and .lnk files.





LoadForm frm1



~DragAcceptFiles(lb1.hWnd, True)



Do

Sleep

Until Me Is Nothing







Sub frm1_MessageProc(ByRef hWnd As Long, ByRef Mess As Long, ByRef wParam As Long, ByRef lParam As Long, ByRef RetVal As Long, ByRef Valid As Boolean)

If Mess = WM_DROPFILES

ExtractFilenamesfromDrag(wParam)

EndIf

End Sub

'



'

Sub ExtractFilenamesfromDrag(ByVal hDrop As Int)

Local pt As POINT

Local Int nFiles, nSkip

Local FName As String



~DragQueryPoint(hDrop, pt)



' get number of files dropped into window

nFiles = DragQueryFile(hDrop, 0xFFFFFFFF, 0, 0) //



If nFiles >= 0



For nSkip = 0 To nFiles - 1

FName = Space$(255) + #0 //Allways initiaslize FName every loop.

' get filename

~DragQueryFile(hDrop, nSkip, FName, Len(FName) - 1)

FName = ZTrim(FName)





If lb1.Find(FName) = -1 //check if file/s already add in listbox.

If GetAttr(FName) And 16 Then // check if its directory.

Else

If Upper(Right(FName, 4)) = ".LNK" //check if its .lnk files.

Else

lb1.AddItem FName ' Add FName and to listbox

EndIf

EndIf

EndIf



Next



EndIf

'##E#

'##B#





~DragFinish(hDrop)



End Sub





Type POINT

x As Long

y As Long

End Type



Declare LIB "shell32.dll"



Declare FunctionA ExtractIcon _

(ByVal hInst As Long, ByVal lpszExeFileName As String, ByVal nIconIndex As Long) As Long

Declare FunctionA DragQueryFile _

(ByVal HDROP As Long, ByVal UINT As Long, ByVal lpStr As String, ByVal ch As Long) As Long

Declare Function DragQueryPoint (ByVal HDROP As Long, lpPoint As POINT) As Long

Declare Sub DragFinish (ByVal hDrop As Long)

Declare Sub DragAcceptFiles (ByVal hwnd As Long, ByVal fAccept As Long)

$DatFile

$FormVersion = 2

:{frm1 105

EAAAAAAAAAAAAAA64XEAA9TRvAQFmJXbxAgElCAAE00UgMFalxGbgQEbnBAAAAACAAAgPAAAACAA

AEAAHAAgAAAbiFDANAAgOOEAAI1QAgkxFBAoXT0EAMICAAAgFAAAACAAAAAAAEQB

$LanguageId = 0409

$DatFile

[scalion]

Excellente démonstration, fonctionnelle, simple, efficace. Juste ce qu'il faut !
Plutôt que de faire un fastidieux copier / enregistrer / ouvrir depuis le post de bulamb0d

Téléchargez directement : DragAndDrop.g32 (2.1 KB)

Merci pour ce code bulamb0d et bonne journée.

[bulamb0d]

your welcome scallion...

google translate....
Excellent demonstration, functional, simple, efficient. Just the right thing!
Rather than make a tedious copy/save/open from the post of bulamb0d

Download directly: DragAndDrop. G32 (2.1 KB)

Thanks for this code bulamb0d and good day.

[(X)]

Apr 30, 2019 20:25:23 GMT 1 scalion said:

Excellente démonstration, fonctionnelle, simple, efficace. Juste ce qu'il faut !
Plutôt que de faire un fastidieux copier / enregistrer / ouvrir depuis le post de bulamb0d

Téléchargez directement : View Attachment

Merci pour ce code bulamb0d et bonne journée.

Est-ce que ça marche avec Win10?  Je n'y arrive pas...

---------------------

Does this work under Win10?  I can't get it to work...

[dragonjim]

It does for me.

Open up a File Explorer window on one side of the screen, then run the code and put the form on the other. Then try and drag a file from the Explorer window to the Form...

[(X)]

I see the drag and drop icon appear but when I release the mouse button the WM_DROPFILES message is never sent and no filename appears in the list box.

Do you see a filename appear in the list box?

I am tracing the _Mess message variable and looking for the WM_DROPFILES (563 | 0x233) message but I never see it.

Do
   If (_Mess == WM_DROPFILES) Trace WM_DROPFILES
   Sleep
Until Me Is Nothing

[dragonjim]

Yes, I see the filename appear - or multiple filenames if I drag across a group (just tried it on a different computer and it still works).

Try putting a Trace in the ExtractFilenamesfromDrag sub-routine...

[(X)]

I tried reinstalling GFA and downloading a fresh copy of the Demo. Still no filename appears.

Exact same behaviour on another PC.  No filename appears. 

(BTW, I am trying to drag and drop the DragAndDrop.G32 file.)

I see the icon change no DnD but no filename is added.

I can perform a DnD from Explorer to another subdirectory or to Desktop, so it's not as if DnD is disabled completely.

[(X)]

I got the original demo working by fiddling with the Windows 10 DEP (Data Execution Prevention) setting (by including the DragAndDrop.exe to be excluded from DEP)

From: www.online-tech-tips.com/windows-xp/disable-turn-off-dep-windows/

What Is DEP & What Does It Do?

According to Microsoft, DEP is :

“…a set of hardware and software technologies that perform additional checks on memory to help prevent malicious code from running on a system.”

Dell simplifies it a bit and tells us that DEP

“…can help protect your computer by monitoring your programs to make sure that they use system memory safely.”

I am trying to get my version working to check if this is really the case.

[(X)]

I tried to download the latest GFA version from Sjouke's site and it seems to have reverted to an older version instead of the one advertised: Download GFA-BASIC 32 2.62.2621 - 14 March 2022.

[dragonjim]

Aug 2, 2022 15:51:45 GMT 1 (X) said:

I got the original demo working by fiddling with the Windows 10 DEP (Data Execution Prevention) setting (by including the DragAndDrop.exe to be excluded from DEP)

Interesting...this may be worth noting for the future.

Glad you managed to get it working.

[scalion]

Aug 2, 2022 0:47:41 GMT 1 (X) said:

Apr 30, 2019 20:25:23 GMT 1 scalion said:

Excellente démonstration, fonctionnelle, simple, efficace. Juste ce qu'il faut !
Plutôt que de faire un fastidieux copier / enregistrer / ouvrir depuis le post de bulamb0d

Téléchargez directement : View Attachment

Merci pour ce code bulamb0d et bonne journée.

Est-ce que ça marche avec Win10?  Je n'y arrive pas...

---------------------

Does this work under Win10?  I can't get it to work...

Yes that's work perfectly on my win10. What happened when you tried ?

[dragonjim]

Aug 2, 2022 17:14:18 GMT 1 (X) said:

I tried to download the latest GFA version from Sjouke's site and it seems to have reverted to an older version instead of the one advertised: Download GFA-BASIC 32 2.62.2621 - 14 March 2022.

View Attachment

Try again. This issue should be fixed now.

If not, please let me know.

[(X)]

Well, I wasn't expecting a week long detour to get a simple demo working, but, I learned something, so, it was worth it!

After a few more attempts to reinstall GFA and changing DEP to the default settings (see previous posts for explanation) I finally got GFA to exhibit the latest version. And the demo works!  My guess is that by targetting an executable produced by GFA, somehow, some part of GFA's executable or related GFAWin32.Ocx may have been affected and GFA wouldn't boot to full version anymore. 

Anyway, that's just what popped into my head as a possible explanation.

This is the demo I came up with, (based of course on the original post):

The file:

Demo Drag And Drop by X.g32 (6.85 KB)

Screen capture:

The code:

'###################################################################
'
' DISCLAIMER:   THIS CODE IS OFFERED AS IS FOR EDUCATIONAL PURPOSES.
'               YOU ARE FREE TO USE, COPY AND DISTRIBUTE.
'               THE USE OF THIS CODE IS AT YOUR OWN RISK.
'               I ACCEPT NO LIABILITY NOR MAKE ANY CLAIM OF
'               CORRECTNESS OR SUITABILITY IN PART OR IN WHOLE.
'
'###################################################################
'
' FILENAME      Demo Drag And Drop by (X).G32
'
' DESCRIPTION   Demonstrates the use of the Drag and Drop functions
'               located in Shell32.  It will not accept folder and
'               .lnk files.
'
' BASED ON      https://gb32.proboards.com/thread/187/source-code-drag-files-listbox
'
' AUTHOR        (X)
' EMAIL         [e-mail]
' WEBSITE       https://gb32.proboards.com/
' STARTED       2022-08-10
' UPDATED       <ISO date>
'
'
$ManifestOff
$Library "GfaWinX"
$Library "UpdateRT"
UpdateRuntime
Mode Date "-"


''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Load form...
'
LoadForm frm1

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Enable drag and drop for specified control...
'
~DragAcceptFiles(lb1.hWnd, True)

''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
' Main loop...
'
Do
 Sleep
Until frm1 Is Nothing

$Group "EVENTS"
Sub frm1_Load
 
 With frm1
   .Caption = App.Name
 EndWith
 
EndSub

Sub frm1_MessageProc(ByRef hWnd As Long, ByRef Mess As Long, ByRef wParam As Long, ByRef lParam As Long, ByRef RetVal As Long, ByRef Valid As Boolean)
 
 If (Mess == WM_DROPFILES)
   ExtractFilenamesfromDrag(wParam)
 EndIf
 
End Sub

Sub frm1_ReSize
 
 Dim m! = 10
 With lb1
   .Left       = m
   .Top        = m
   .Width      = frm1.ScaleWidth - 2 * m
   .Height     = frm1.ScaleHeight - 2 * m
 EndWith
 
EndSub

$Group "DECLARATIONS"
Declare LIB "shell32.dll"
Declare FunctionA       ExtractIcon     (ByVal hInst%, ByVal lpszExeFileName As String, ByVal nIconIndex%) As Long
Declare FunctionA       DragQueryFile   (ByVal hDrop%, ByVal UINT%, ByVal lpStr As String, ByVal ch%) As Long
Declare Function        DragQueryPoint  (ByVal hDrop%, lpPoint As POINT) As Long
Declare Sub             DragFinish      (ByVal hDrop%)
Declare Sub             DragAcceptFiles (ByVal hwnd%, ByVal fAccept%)

$Group "PROCEDURES"
Sub ExtractFilenamesfromDrag(ByVal hDrop As Int)
 
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 ' Define a few local variables...
 '
 Local pt As POINT
 Local Int nFiles, nSkip
 Local FName As String
 
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 ' Pass the location (x,y point) the files were dropped...
 '
 ~DragQueryPoint(hDrop, pt)
 
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 ' Get number of files dropped into window
 '
 nFiles = DragQueryFile(hDrop, 0xFFFFFFFF, 0, 0)
 
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 ' Check if any files are selected...
 '
 If (nFiles => 0)
   
   ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
   ' Go through all the selected files...
   '
   For nSkip = 0 To nFiles - 1
     
     ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
     ' Always initiaslize FName every loop.
     '
     FName = Space$(255) + #0
     
     ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
     ' Get filename
     '
     ~DragQueryFile(hDrop, nSkip, FName, Len(FName) - 1)
     
     FName = ZTrim(FName)
     
     ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
     ' Check if file is already added in listbox.
     '
     If lb1.Find(FName) = -1
       
       ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
       ' Check if it is a directory.
       '
       If GetAttr(FName) And 16 Then
         // Do nothing...
       Else
         
         If Upper(Right(FName, 4)) = ".LNK" //check if its .lnk files.
           // Do nothing...
         Else
           
           ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
           ' Add FName and to listbox
           '
           lb1.AddItem FName
           
         EndIf
         
       EndIf
     EndIf
   Next
 EndIf
 
 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 ' Lets finish this!
 '
 ~DragFinish(hDrop)
 
End Sub