docs : by rememberSaveable, callback (#3)

delegate property by를 사용하면 변수로 바꾼다.
- 알아서 set, get을 해준다.
```
var isFavorite by rememberSaveable {
mutableStateOf(false)
}
```

callback

@Composable
fun ImageCard(
    isFavorite : Boolean,
        //callBack
    onTabFavorite: (Boolean) -> Unit
){

  IconButton(onClick = {
      //callBack
      onTabFavorite(!isFavorite)
  }){ }

전체코드

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            //delegate property by를 사용하면 변수로 바꾼다.
            //알아서 set, get을 해준다.
            var isFavorite by rememberSaveable {
                mutableStateOf(false)
            }
            ImageCard(
                isFavorite = isFavorite,
            ){
                favorite ->
                isFavorite = favorite
            }
        }
    }
}

@Composable
fun ImageCard(
    isFavorite : Boolean,
    //callBack
    onTabFavorite: (Boolean) -> Unit
){
    Card(
        modifier = Modifier
            .fillMaxWidth(0.5f)
            .padding(16.dp),
        shape = RoundedCornerShape(8.dp),
        elevation = CardDefaults.cardElevation(5.dp)
    ){
        Box(
            modifier = Modifier.height(200.dp)
        ){
            Image(
                painter = painterResource(id = R.drawable.poster),
                contentDescription = "poster",
                contentScale = ContentScale.Crop
            )
            Box(
                modifier = Modifier.fillMaxSize(),
                contentAlignment = Alignment.TopEnd
            ){
                IconButton(onClick = {
                    //callBack
                    onTabFavorite(!isFavorite)
                }){
                    Icon(
                        imageVector = if (isFavorite) Icons.Default.Favorite else Icons.Default.FavoriteBorder,
                        contentDescription = "favorite",
                        tint = Color.White
                    )
                }
            }
        }
    }
}

전체코드(@Composable ImageCard의 modifier를 외부에서 주입받게 수정)

class MainActivity : ComponentActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContent {
        //delegate property by를 사용하면 변수로 바꾼다.
        //알아서 set, get을 해준다.
        var isFavorite by rememberSaveable {
            mutableStateOf(false)
        }
        ImageCard(
            modifier = Modifier.fillMaxWidth(0.5f)
                .padding(16.dp),
            isFavorite = isFavorite,
        ){
            favorite ->
            isFavorite = favorite
        }
    }
}
}

@Composable
fun ImageCard(
modifier: Modifier = Modifier,
isFavorite : Boolean,
//callBack
onTabFavorite: (Boolean) -> Unit
){
Card(
    modifier = modifier,
    shape = RoundedCornerShape(8.dp),
    elevation = CardDefaults.cardElevation(5.dp)
){
    Box(
        modifier = Modifier.height(200.dp)
    ){
        Image(
            painter = painterResource(id = R.drawable.poster),
            contentDescription = "poster",
            contentScale = ContentScale.Crop
        )
        Box(
            modifier = Modifier.fillMaxSize(),
            contentAlignment = Alignment.TopEnd
        ){
            IconButton(onClick = {
                //callBack
                onTabFavorite(!isFavorite)
            }){
                Icon(
                    imageVector = if (isFavorite) Icons.Default.Favorite else Icons.Default.FavoriteBorder,
                    contentDescription = "favorite",
                    tint = Color.White
                )
            }
        }
    }
}
}

philipy355 / inflearn-compose

docs : by rememberSaveable, callback (#3) #8