LazyColumn does not scroll if using TextFields as child - android-jetpack-compose

#Composable
fun init() {
LazyColumn(Modifier.fillMaxSize()) {
for (i in 0..10) {
item { Box(Modifier.padding(15.dp)) { TextField("Hallo$i", modifier = Modifier.fillMaxWidth(), onValueChange = {}) } }
}
}
}
If i have something simple as this list with textfields
then the textfields will not let me scroll down the column.
Only works if i scroll down next to the textfields.
Tried also with readonly/disabled textfield.
is there a way to overcome this behaviour?
maybe a way to disable focus on textfield if scrolled?
I am using jetbrains-compose for desktop version (0.5.0-build245)
but can also be the same as in the jetpack-compose for android (did not try)

for the moment because i don't find any other solution i will use this workaround
using a invisible box above the text field and change the state accordingly
#Composable
fun init() {
LazyColumn(Modifier.fillMaxSize()) {
for (i in 0..10) {
item {
val isfocused = remember { mutableStateOf(false) }
val focusRequester = FocusRequester()
Box(Modifier.padding(15.dp)) {
TextField("Hallo$i", modifier = Modifier.fillMaxWidth().focusRequester(focusRequester).onFocusChanged {
isfocused.value = it.isFocused
}, onValueChange = {})
if (!isfocused.value)
Box(
modifier = Modifier
.matchParentSize()
.alpha(0f)
.clickable(onClick = {
isfocused.value = true
focusRequester.requestFocus()
}),
)
}
}
}
}
}

Related

How to prevent accessibility focus from moving to controls behind ExposedDropdownMenuBox

I am having an issue where the accessibility focus is going to controls behind the PopUp Window when using a ExposedDropdownMenuBox
If there is a single ExposedDropdownMenuBox everything works as expected, but when I add a second ExposedDropdownMenuBox or another control the focus goes to the second ExposedDropdownMenuBox before going to the PopUp Window.
GIF of single dropdown behavior
https://giphy.com/gifs/gapy0XK1CGmbyltJxU
GIF of two dropdowns on the same screen
https://giphy.com/gifs/WkL5TcMWlumfcGHPmD
Source
#Composable
fun Screen() {
Column (
modifier = Modifier
.wrapContentSize(Alignment.TopCenter)
.padding(top = 48.dp)
) {
Text(
text = stringResource(id = R.string.greeting),
fontSize = 30.sp,
modifier = Modifier.padding(bottom = 24.dp)
)
LocaleDropdownMenu()
Spacer(modifier = Modifier.height(8.dp))
// LocaleDropdownMenu()
}
}
#OptIn(ExperimentalMaterialApi::class)
#Composable
fun LocaleDropdownMenu() {
val localeOptions = mapOf(
R.string.en to "en",
R.string.fr to "fr",
R.string.hi to "hi",
R.string.ja to "ja"
).mapKeys { stringResource(it.key) }
// boilerplate: https://developer.android.com/reference/kotlin/androidx/compose/material/package-summary#ExposedDropdownMenuBox(kotlin.Boolean,kotlin.Function1,androidx.compose.ui.Modifier,kotlin.Function1)
var expanded by remember { mutableStateOf(false) }
ExposedDropdownMenuBox(
expanded = expanded,
onExpandedChange = {
expanded = !expanded
}
) {
TextField(
readOnly = true,
value = stringResource(R.string.language),
onValueChange = { },
trailingIcon = {
ExposedDropdownMenuDefaults.TrailingIcon(
expanded = expanded
)
}
)
ExposedDropdownMenu(
expanded = expanded,
onDismissRequest = {
expanded = false
}
) {
localeOptions.keys.forEach { selectionLocale ->
DropdownMenuItem(
onClick = {
expanded = false
// set app locale given the user's selected locale
AppCompatDelegate.setApplicationLocales(
LocaleListCompat.forLanguageTags(
localeOptions[selectionLocale]
)
)
},
content = { Text(selectionLocale) }
)
}
}
}
}
A repository that reproduces this issue is here:
https://github.com/dazza5000/ExposedDropdownMenuBox-accessibility-issue

How to add and delete items in a lazyVerticalGrid Column in jetpack compose

I'm new to jetpack compose and I am just looking for a way to add and delete items from a lazyVerticalGrid using jetpack compose from a pop-up menu. Nothing complicated, just simple code to make me easily understand what I have to do
This is pretty easy as other LazyLists. You need to have a list that you can trigger recomposition after delete, add or update and use unique keys to not recompose your entire list and limit recomposition to a range of items.
val list = remember { mutableStateListOf<Snack>() }
You can remove or add inside you menu by changing this list
Adding, removing items or replacing any items with new one, to update you need to pass a new instance of object, will trigger recomposition
#Composable
private fun GridExample() {
val scrollState = rememberLazyListState()
val coroutineScope = rememberCoroutineScope()
val list = remember { mutableStateListOf<Snack>() }
Column {
LazyVerticalGrid(
contentPadding = PaddingValues(12.dp),
modifier = Modifier
.weight(1f)
.background(backgroundColor),
columns = GridCells.Fixed(3),
content = {
items(items = list,
key = { snack: Snack ->
snack.name
}) { snack: Snack ->
GridSnackCard(snack = snack)
}
}
)
Row(
modifier = Modifier.padding( 8.dp),
horizontalArrangement = Arrangement.SpaceEvenly
) {
Button(
modifier = Modifier.weight(1f),
onClick = {
if (list.size < snacks.size) {
list.add(snacks[list.size])
}
},
shape = RoundedCornerShape(8.dp)
) {
Text(text = "Add")
}
Spacer(modifier = Modifier.width(10.dp))
Button(
modifier = Modifier.weight(1f),
onClick = {
if (list.size > 0) {
list.removeLast()
}
},
shape = RoundedCornerShape(8.dp)
) {
Text(text = "Remove")
}
}
}
}

I have a composable not setting button text as expected; wondering why. Have a reproducible example

this started as a new compose project
with the following code the intent is to change the text to the picked time. The code is commented where the behavior occurs
class MainActivity : ComponentActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContent {
MyApplicationTestTheme {
// A surface container using the 'background' color from the theme
Surface(
modifier = Modifier.fillMaxSize(),
color = MaterialTheme.colors.background
) {
TimeCardButton(id = 1, symbol ="In", enabled=true,modifier = Modifier) { entry ->
Log.d("click", "$entry result")
}
}
}
}
}
}
data class TimeCardEntry(val id: Int = -1, var entry: String = "")
#Composable
fun TimeCardButton(
id: Int,
symbol: String,
enabled: Boolean = false,
modifier: Modifier,
onValueChange: (TimeCardEntry) -> Unit = {},
) {
// Value for storing time as a string
val timeState = remember {
mutableStateOf(TimeCardEntry(id, symbol))
}
val validState = remember {
timeState.value.entry.trim().isNotEmpty()
}
val mTime = remember { mutableStateOf(symbol) }
if (enabled) {
// Fetching local context
val mContext = LocalContext.current
// Declaring and initializing a calendar
val mCalendar = Calendar.getInstance()
val mHour = mCalendar[Calendar.HOUR_OF_DAY]
val mMinute = mCalendar[Calendar.MINUTE]
// Creating a TimePicker dialog
val mTimePickerDialog = TimePickerDialog(
mContext,
{ _, mHour: Int, mMinute: Int ->
timeState.value.entry = "$mHour:$mMinute"
mTime.value = "$mHour:$mMinute"
onValueChange(timeState.value)
}, mHour, mMinute, false
)
Box(
contentAlignment = Alignment.Center,
modifier = Modifier
.clip(CircleShape)
.then(modifier)
) {
TextButton(onClick = { mTimePickerDialog.show() }.also {
Log.d("click", "id $id clicked!") }) {
Column() {
// if I use just this it works [in changes to the time picked]
//Text(text = mTime.value)
// if i use both of these BOTH are set when the date picker is invoked
// if I just use the second one alone, the text never changes
Text(text = timeState.value.entry)
}
}
}
} else {
Box(
contentAlignment = Alignment.Center,
modifier = Modifier
.clip(CircleShape)
.then(modifier)
) {
Text(text = symbol, color =
MaterialTheme.colors.onBackground)
}
}
}
#Preview(showBackground = true)
#Composable
fun DefaultPreview() {
MyApplicationTestTheme {
}
}
First of all how to fix it:
Your problem basically is this. The easiest way to fix it would be to reassign the whole value of TimeState, not just entry by calling
timeState.value = timeState.value.copy(entry = "$mHour:$mMinute")
The reason it doesn't work with only the second one is that the change of a property doesn't trigger recomposition, even if the variable containing it is a mutableState. To fix (as outlined in the answers to the question linked above) this you either have to reassign the whole variable or make the parameter you want to observe observable (for example changing the String to State<String>)
PS: if you use by with mutableStateOf (i.e. val timeState = remember { mutableStateOf(TimeCardEntry(id, symbol)) }) you don't have to use .value every time. I find that a lot cleaner and more readable

How to show keyboard with Jetpack Compose?

How can I slide in the keyboard?
I tried:
val keyboardController: SoftwareKeyboardController? = LocalSoftwareKeyboardController.current
keyboardController?.show()
But it does not work. What am I missing? Maybe some Manifest flags?
To show keyboard in Compose:
val showKeyboard = remember { mutableStateOf(true) }
val focusRequester = remember { FocusRequester() }
val keyboard = LocalSoftwareKeyboardController.current
OutlinedTextField(
modifier = Modifier
.fillMaxWidth()
.focusRequester(focusRequester),
value = value,
textStyle = MaterialTheme.typography.body2,
onValueChange = { onValueChange(it)},
label = { Text(label) }
)
// LaunchedEffect prevents endless focus request
LaunchedEffect(focusRequester) {
if (showKeyboard.equals(true)) {
focusRequester.requestFocus()
delay(100) // Make sure you have delay here
keyboard?.show()
}
}
Locked for 3 hours. There are disputes about this answer’s content being resolved at this time. It is not currently accepting new interactions.
What's the issue with the official method?
fun showSoftKeyboard(view: View) {
if (view.requestFocus()) {
val imm = getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
imm.showSoftInput(view, InputMethodManager.SHOW_IMPLICIT)
}
}
Read more here.
This method works if you just use it like this:
showSoftKeyboard(AndroidView(context))
You could also try eliminating the parameter entirely by placing the AndroidView in the function's body instead.

Jetpack Compose - Scroll to focused composable in Column

I have UI like this:
val scrollState = rememberScrollState()
Column(
modifier = Modifier
.fillMaxSize(1F)
.padding(horizontal = 16.dp)
.verticalScroll(scrollState)
) {
TextField(...)
// multiple textfields
TextField(
//...
modifier = Modifier.focusOrder(countryFocus).onFocusChanged {
if(it == FocusState.Active) {
// scroll to this textfield
}
},
)
}
I have multiple TextFields in this column and when one of them is focused I want to scroll Column to it. There is a method in scrollState scrollState.smoothScrollTo(0f) but I have no idea how to get a focused TextField position.
Update:
It seems that I've found a working solution. I've used onGloballyPositioned and it works. But I'm not sure if it the best way of solving this.
var scrollToPosition = 0.0F
TextField(
modifier = Modifier
.focusOrder(countryFocus)
.onGloballyPositioned { coordinates ->
scrollToPosition = scrollState.value + coordinates.positionInRoot().y
}
.onFocusChanged {
if (it == FocusState.Active) {
scope.launch {
scrollState.smoothScrollTo(scrollToPosition)
}
}
}
)
There is a new thing in compose called RelocationRequester. That solved the problem for me. I have something like this inside of my custom TextField.
val focused = source.collectIsFocusedAsState()
val relocationRequester = remember { RelocationRequester() }
val ime = LocalWindowInsets.current.ime
if (ime.isVisible && focused.value) {
relocationRequester.bringIntoView()
}
Also you can use BringIntoViewRequester
//
val bringIntoViewRequester = remember { BringIntoViewRequester() }
val coroutineScope = rememberCoroutineScope()
//--------
TextField( ..., modifier = Modifier.bringIntoViewRequester(bringIntoViewRequester)
.onFocusEvent {
if (it.isFocused) {
coroutineScope.launch {
bringIntoViewRequester.bringIntoView()
}
}
}
It seems that using LazyColumn and LazyListState.animateScrollToItem() instead of Column could be a good option for your case.
Reference: https://developer.android.com/jetpack/compose/lists#control-scroll-position
By the way, thank you for the information about onGloballyPositioned() modifier. I was finding a solution for normal Column case. It saved me a lot of time!
Here's some code I used to make sure that the fields in my form were not cut off by the keyboard:
From: stack overflow - detect when keyboard is open
enum class Keyboard {
Opened, Closed
}
#Composable
fun keyboardAsState(): State<Keyboard> {
val keyboardState = remember { mutableStateOf(Keyboard.Closed) }
val view = LocalView.current
DisposableEffect(view) {
val onGlobalListener = ViewTreeObserver.OnGlobalLayoutListener {
val rect = Rect()
view.getWindowVisibleDisplayFrame(rect)
val screenHeight = view.rootView.height
val keypadHeight = screenHeight - rect.bottom
keyboardState.value = if (keypadHeight > screenHeight * 0.15) {
Keyboard.Opened
} else {
Keyboard.Closed
}
}
view.viewTreeObserver.addOnGlobalLayoutListener(onGlobalListener)
onDispose {
view.viewTreeObserver.removeOnGlobalLayoutListener(onGlobalListener)
}
}
return keyboardState
}
and then in my composable:
val scrollState = rememberScrollState()
val scope = rememberCoroutineScope()
val isKeyboardOpen by keyboardAsState()
if (isKeyboardOpen == Keyboard.Opened) {
val view = LocalView.current
val screenHeight = view.rootView.height
scope.launch { scrollState.scrollTo((screenHeight * 2)) }
}
Surface(modifier = Modifier
.fillMaxHeight()
.verticalScroll(scrollState),
) {
//Rest of your Composables, Columns, Rows, TextFields, Buttons
//add this so the screen can scroll up and keyboard cannot cover the form fields - Important!
/*************************************************/
if (isKeyboardOpen == Keyboard.Opened) {
Spacer(modifier = Modifier.height(140.dp))
}
}
Hope it helps someone. I was using:
val bringIntoViewRequester = remember { BringIntoViewRequester() }
val scope = rememberCoroutineScope()
val view = LocalView.current
DisposableEffect(view) {
val listener = ViewTreeObserver.OnGlobalLayoutListener {
scope.launch { bringIntoViewRequester.bringIntoView() }
}
view.viewTreeObserver.addOnGlobalLayoutListener(listener)
onDispose { view.viewTreeObserver.removeOnGlobalLayoutListener(listener) }
}
Surface(modifier.bringIntoViewRequester(bringIntoViewRequester)) {
///////////rest of my composables
}
But this did not work.

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