Please add zoom function？

[klower]

would you please add zoom function?

[iamutkarshtiwari]

@klower Could you please elaborate a bit more?
Which part of the app would you want to add the zoom function in?

[hoangknguyen1807]

@iamutkarshtiwari
In the EditImageActivity, only the addTextFragment works well with Zooming, the rest doesn't.
I wonder what these 2 classes do :

Are they for zooming the mainView image in each editing fragment?
Please explain, thank you!