MobileToolbarButton.Icon
From Xojo Documentation
Property (As Picture )
aMobileToolbarButton.Icon = newPictureValue
or
PictureValue = aMobileToolbarButton.Icon
Supported on Mobile.
or
PictureValue = aMobileToolbarButton.Icon
Supported on Mobile.
Specifies an picture to display for the button's icon.
Notes
If you have both a Caption and Icon specified, then only the Icon appears.
Only the mask for the image is used, displayed using the tint color for iOS (currently blue).
For iOS, Apple provides guidelines on icon size.