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Reply To: Clearing captured still images

Forums › TWAIN Classic › Clearing captured still images › Reply To: Clearing captured still images

May 2, 2007 at 9:11 pm #23651
gabe
Participant
  • Topics - 9
  • Replies - 583
  • Total Posts - 592

That could be, I’ve been wrong before. But I know what EnableDs does. EnableDs does not produce a dialog from within twain_32, it signals the driver to either scan or show the vendor Ui. And part where you set ShowUi= False – that is the part where you are telling twain_32.dll to scan and where you’re requesting (not telling, just requesting) the driver to not show it’s Ui.

From 7-224 of the twain spec found here :

Description
This operation causes three responses in the Source:
• Places the Source into a “ready to acquire” condition. If the application raises the
Source’s user interface (see #2, below), the Source will wait to assert MSG_XFERREADY
until the “GO” button in its user interface or on the device is clicked. If the application
bypasses the Source’s user interface, this operation causes the Source to become
immediately “armed”. That is, the Source should assert MSG_XFERREADY as soon as it
has data to transfer.
• The application can choose to raise the Source’s built-in user interface, or not, using this
operation. The application signals the Source’s user interface should be displayed by
setting pUserInterface->ShowUI to TRUE. If the application does not want the Source’s
user interface to be displayed, or wants to replace the Source’s user interface with one of
its own, it sets pUserInterface->ShowUI to FALSE. If activated, the Source’s user
interface will remain displayed until it is closed by the user or explicitly disabled by the
application (see Note).
• Terminates Source’s acceptance of “set capability” requests from the application.
Capabilities can only be negotiated in State 4 (unless special arrangements are made
using the CAP_EXTENDEDCAPS

Keep reading his code (or the twain spec), and you’ll see that eventually (if you’re using native transfer mode) you get a pointer back. Thats all, just a pointer. You don’t get a dialog from twain_32.dll by calling EnableDs. Now a dialog may come up, but that dialog wasn’t created by twain_32.

But you’re right on the last point, I don’t think I can help you.

Good Luck,

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