Saturday, March 27, 2021

jetpack compose - Animate visibility change

MainActivity.kt

package com.cfsuman.jetpackcompose

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.activity.compose.setContent
import androidx.compose.animation.AnimatedVisibility
import androidx.compose.animation.ExperimentalAnimationApi
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.material.Button
import androidx.compose.material.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp

class MainActivity : AppCompatActivity() {
    @ExperimentalAnimationApi
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            MainContent()
        }
    }


    @ExperimentalAnimationApi
    @Composable
    fun MainContent(){
        val isVisible = remember { mutableStateOf(value = false) }

        Column(
            modifier = Modifier
                .background(Color.LightGray)
                .fillMaxSize()
                .padding(16.dp),
            verticalArrangement = Arrangement.spacedBy(16.dp)
        ) {
            Button(
                onClick = { isVisible.value = !isVisible.value }
            ) {
                Text(
                    text = if (isVisible.value) "Hide" else "Show"
                )
            }

            AnimatedVisibility(isVisible.value) {
                Box(
                    modifier = Modifier
                        .fillMaxWidth()
                        .height(275.dp)
                        .background(Color.Red)
                )
            }
        }
    }


    @Preview
    @Composable
    fun ComposablePreview(){
        //MainContent()
    }
}