Sunday, March 7, 2021

jetpack compose - How to use Slider

MainActivity.kt

package com.cfsuman.jetpackcompose

import androidx.appcompat.app.AppCompatActivity
import android.os.Bundle
import androidx.activity.compose.setContent
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.material.*
import androidx.compose.runtime.Composable
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import kotlin.math.roundToInt

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

        setContent {
            MainContent()
        }
    }


    @Composable
    fun MainContent(){
        val sliderPosition = remember { mutableStateOf(0f)}
        val intPosition = (sliderPosition.value * 100).roundToInt()

        Column(
            Modifier
                .background(Color(0xF5F5F5))
                .fillMaxSize()
                .padding(16.dp),
            horizontalAlignment = Alignment.CenterHorizontally
        ) {
            Text(
                "$intPosition",
                fontWeight = FontWeight.Bold,
                fontSize = 25.sp
            )
            
            Slider(
                value = sliderPosition.value,
                onValueChange = { sliderPosition.value = it }
            )
        }
    }


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