Find the constructor parameter icon or whatever it is. Now change its type from IconData (mostly) to Widget and now find the usage with simple searching/looking for the keyword and adjust/fit in the changed icon parameter as a Widget . because Icon() is also a widget which used the earlier IconData widget.
Read moreHow do you use icons on Flutter?
How to Generate Custom Icons in Flutter
Read moreHow do I put an image in my icon on Flutter?
Steps to Add an Image:
Read moreHow do I use an image as an icon?
Go to menu Image > New Device Image, or right-click in the Image Editor pane and choose New Device Image. Select the type of image you want to add . You can also select Custom to create an icon whose size isn’t available in the default list.
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