Butterknife: How to optionally bind nullable views in Kotlin

[ZakTaccardi]

I'm trying to bind a nullable (optional) view in kotlin (not using KotterKnife), and I'm getting this error.

@BindView fields must not be private or static

What's the workaround? Tried the below with no luck (same error)

@field:[BindView(R.id.home_toolbar) Nullable] var toolbar: Toolbar? = null

[JakeWharton]

That's a property whose backing field is private. Add @JvmField to generate a public field instead.

[ZakTaccardi]

Thanks Jake, coming through in the clutch.

Example of fix below.

@BindView(R.id.home_toolbar) @Nullable @JvmField var toolbar: Toolbar? = null

[joshfriend]

The @Nullable annotation is not required because ButterKnife will assume the binding is optional if it finds any annotation named "Nullable" on the field. An optional field in Kotlin seen in java as a field with the org.jetbrains.annotations.Nullable annotation applied, which ButterKnife understands. Thus, you can write the binding as:

@BindView(R.id.home_toolbar) @JvmField var toolbar: Toolbar? = null