Assignment of null to File variable in Flutter

Question

How can I assign null to File variable. I got error when assigning null to File variable.

File myImage=null;
(myImage==null)?
 CircleAvatar(
    backgroundImage:AssetImage('assets/user_new.png'),
    backgroundColor: Colors.cyanAccent,
    radius: 70,
    )
    :
 CircleAvatar(
    backgroundImage:FileImage(myImage),
    backgroundColor: Colors.cyanAccent,
    radius: 70,
    )

Answer 1

I suppose you have nullsafety enabled. With nullsafety a variable declared without a ? cannot be null. To fix your issue do the following.

File? myImage = null;

Answer 2

In Flutter null safety is a thing.

With it, no variables can be null if they haven't got a ?. Add a question mark to your File declaration, as:

File? myImage = null;

Down in your code, you will need to check if myImage is null (since now it can be) if you want to assign it to the backgroundImage parameter. You have 2 choices for this:

backgroundImage:FileImage(myImage!) //Null check: Exception throw only if null
backgroundImage:FileImage(myImage ?? _anotherWorkingFile) //If: use another standard file if null