[TYPO3-mvc] Changing context in widget-viewhelper?

[Alexander Wende]

Dear list,

I have a simple extbase extension. In the new-form I have an upload
field for uploding an image. Now if the users do some changes in the
edit form without uploading a new image, the stored image get lost.

So I added an upload-widget which renders the image, if set. If no image
is set or the user clicks on the image the widget renders an upload
field for updating the image. The widget works fine but if the users
changed some fields in the edit field the insert data get lost when the
widget performs the subrequest before updating.

Is there any possibility to change the context of the mainrequest? I
tried to change the context at the WidgetViewHelper but it doesn't work.

Regards
Alex