[FIXED] painterResource for null IDs

Issue

I have a list of images and a variable with can be anything from -1 to 13.
But the list contains only 3 indexes, so I have set a condition.

items[if(myInt == null) R.drawable.placholder else myInt

But it crashes my app with this error,

java.lang.ArrayIndexOutOfBoundsException: length=4; index=4

My Code

val items = listOf(R.drawable.red, R.drawable.green, R.drawable.blue)
Image(painter = painterResource(items[if(myInt==null) R.drawable.placholder else myInt]), contentDescription = null)

Solution

The shortest solution is using kotlin getOrElse. You can specify -1 instead of null:

items.getOrElse(myInt ?: -1) { failedIndex -> R.drawable.ic_undo }

A more detailed solution is to check if item.indices contains your index:

if (myInt != null && items.indices.contains(myInt)) {
    items[myInt]
} else {
    R.drawable.ic_undo
}

Answered By - Philip Dukhov