JetPack Compose, animateColorAsSate

Question

Getting error when use this line:

val surfaceColor: Color by animateColorAsState( if (isExpanded) MaterialTheme.colors.primary else MaterialTheme.colors.surface, )

It showing the following warning:

Property delegate must have a 'getValue(Nothing?, KProperty*>)' method. None of the following functions are suitable. State.getValue(Any?, KProperty<>)   where T = Color for   inline operator fun State.getValue(thisObj: Any?, property: KProperty<>): T defined in androidx.compose.runtime

Answer 1

Make sure you are using correct import statements.

Compare and try replacing your import statements with correct one from below.

import androidx.compose.animation.animateColorAsState
import androidx.compose.foundation.clickable
import androidx.compose.foundation.layout.Column
import androidx.compose.material.MaterialTheme
import androidx.compose.runtime.*
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color


@Composable
fun YourFunction() {

    var isExpanded by remember { mutableStateOf(false) }

    val surfaceColor: Color by animateColorAsState(
        if (isExpanded) MaterialTheme.colors.primary else MaterialTheme.colors.surface
    )

    Column(
        modifier = Modifier.clickable { isExpanded = !isExpanded }
    ) {

    }
}