Can I implement magnify Glass in windows image viewer

Hi,

I have a windows Imageviewer view image file , I want to add magglass to the Imageviewer, how can I use the L_StartMagGlass to implement it .
because the imageviewer.bitmap is a windows handle, and the second param of L_StartMagGlass is pBitmapHandle,
is there any way to convert the imageviewer.bitmap
to pBitmapHandle ?

I am using v16 c dll with delphi.

Thanks.

jacky

You can not use our MagGlass functions on the Windows ImageViewer. To use our MagGlass functions, you need to have a LEADTOOLS BITMAPHANDLE that contains the image and use our painting functions to paint the loaded image on a Windows Device Context Handle (HDC).

This means if the image is in a disk file, you need to use the LEADTOOLS loading function to load it. If it's in some other object or image type, you need to convert it to a LEAD bitmap first.

hi
thanks for answer my question, and I has another question that is I want to use the method of press the keyboard "M" key always down to show the magnify glass , can you help me to implement this idea?

thanks.

Unfortunately, you can not do that using the MagGLass, you can do that using the Zoom View functionality. There is a demo that shows how to use that. You can find the demo in this folder:

[LEADTOOLS 16]\Examples\CDLL\ZoomView

but the Zoom view's shape is rectangle, I want it's shape is circle.

When starting the magglass, pass the MAGGLASS_MANUAL_UPDATE flag in the MAGGLASSOPTIONS.uMagGlassFlags property.  This will mean that the magglass will not automatically handle the mouse events and you are responsible for everything the magglass does.  

The documentation for the MAGGLASSOPTIONS has more details, but for the most part you will need to use the L_ShowMagGlass and L_SetMagGlassPos functions.  You should therefore be able to handle the mouse events and only show the magglass when the 'M' key is down.  There is an example in the help file showing how to use these functions.