Zooming in and out on an image when I only have a touchscreen?

[another_novice]

Hello all,

I'm setting up an inspection application which will only have a touchscreen. However the user will want to zoom in and out on images. Zooming in is okay - just grab the magnifying lens and click - but with no shift key to hold down I can't see how to zoom out.

Anyone got any suggestions?

[udka · Accepted solution]

Maybe keep one button/contol logic and connect it to zoom factor property of image indicator.

-When operator presses button/control you can change the zoom level

[Hatef.fouladi · Accepted solution]

you can use property node zooming tool 

then you can create bottom for zoom and unzoom by algorithm 

[another_novice]

For anyone else with this issue, here's what I did: following the advice of the two experts above, I right clicked on the image (in the block diagram) and created a property node. Scrolling to the bottom of the list of properties I found one to zoom-to-fit. Just set that to read and wire a boolean control. Now I tap on the image to zoom in, use scrollbars to move around, and tap the boolean (set to latch) to zoom back out.

Thanks for the help guys!