androidkotlinevent-handlingandroid-jetpack-composeandroid-compose-card

Event Handling on a Jetpack Compose Card


I have a music player app - on my screen, I have cards displaying information about tracks. When I tap on one card, the player should play its track.

@Composable
fun TrackCard(track: Track) {
    Card(
        modifier = Modifier.padding(5.dp).fillMaxWidth(),
        contentColor = Color.Black
    ) {
        Column(modifier = Modifier.padding(10.dp)) {
            ArtistName(text = track.artist.name)
            Headline(text = track.title)
            AlbumName(text = track.album.title)
        }
    }
}

I tried it with adding a Clickable on its Modifier like this: clickable(onClick = {}) In order to let the track play, I need another param for my TrackCard, the player itself. As I want to keep UI code separate, I was wondering if I could add an Event Listener and access play the track from there? (Also I would like to catch the different type of events like a long pressed touch etc. for different event handling as well)

The track cards get initialized like this:

@Composable
private fun ResultList(model: PlayerModel) {
    with(model) {
            LazyColumn(state = rememberLazyListState()) {
                items(tracks) {
                    TrackCard(it)
                }
            }
        }
    }
}

How would I accomplish this?


Solution

  • It depends by your MediaPlayer implementation, but you can decouple the card and the media player composables using something like:

    val (source, setSource) = remember { mutableStateOf (
        "mediaToPlay")
    }
    
    //MediaPlayer(source)
    LazyColumn() {
        items(listTrack){
            TrackCard(it, onClickStartSource = {setSource(it.source)})
        }
    }
    

    with:

    @Composable
    fun TrackCard(track: Track, onClickStartSource : () -> Unit) {
    
        Card(
            modifier = Modifier
                .padding(5.dp)
                .fillMaxWidth(),
             onClick = {onClickStartSource},
                //your code
        ){ /* ... */ }
    

    Also you can use the combinedClickable modifier to get the different click events:

    Card(
        modifier = Modifier
            .padding(5.dp)
            .fillMaxWidth()
            //.clickable(onClick = onClickStartSource)
            .combinedClickable(
                onLongClick = { /*....*/ },
                onDoubleClick ={ /*....*/ }),
        contentColor = color
    )