I have liveData of market data. I want one market data object which have highest 'volume'. Here, volume is string value("277927.5793846733451135"), it could be null also.
I am using below code to achieve this. but, its not working.
viewModel.marketlist.observe(this as LifecycleOwner, { marketdata ->
val marketData = marketdata.getOrNull()
if(marketData !=null) {
val mData: MarketData? = marketData.marketData?.maxByOrNull { checkNotNull(it.volume) }
if (mData != null) {
binding.textViewPrice.text = mData.price
}
}
else {
//TODO
}
})
Any help would be appreciated!
You should be able to do something like this:
viewModel.marketList.observe(viewLifecycleOwner) { marketData ->
val maxData = marketData.getOrNull()?.marketData?.let { dataValues ->
dataValues.maxByOrNull { it.volume?.toDoubleOrNull() ?: -1.0 }
}
if (maxData != null) {
binding.textViewPrice.text = maxData.price
}
}
I cleaned up the observe call a bit, then I'm checking if marketData.getOrNull().marketData is null right away with my let { ... } block.
If you do have marketData (the inner one), it'll then safely call maxByOrNull { it.volume }.
Related
I have a god view model for every thing I know this is wrong
but I am just experimenting with Flow
I have these two State flow variables in view model
private val _currentRestroMenu = MutableStateFlow<State<Menu>>(State.loading())
private val _userCart = MutableStateFlow(CustomerCart())
val currentRestroMenu: StateFlow<State<Menu>> = _currentRestroMenu
val userCart: StateFlow<CustomerCart> = _userCart
Below functions get data from server and update above state flow
private fun getRestroMenuFromCloudAndUpdateData(restroId: String) = viewModelScope.launch {
fireStoreRepository.getRestroMenu(restroId).collect { state ->
when (state) {
is State.Success -> {
_currentRestroMenu.value = State.success(state.data)
dataHolderMenuOnSearch = state.data
if (!viewedRestroMenu.contains(state.data)) {
viewedRestroMenu.add(state.data)
}
}
is State.Failed -> {
_currentRestroMenu.value = State.failed(state.message)
}
is State.Loading -> {
_currentRestroMenu.value = State.loading()
}
}
}
}
private fun getCart() = viewModelScope.launch(Dispatchers.IO) {
if (currentCart.cartEmpty) {
fireStoreRepository.getUserCartInfoFromCloud(dataStoreRepository.readFileDataStoreValue.first().savedUserId)
.collect { cartState ->
when (cartState) {
is State.Success -> {
_userCart.update {
it.copy(
cartId = cartState.data.cartId,
cartEmpty = cartState.data.cartEmpty,
cartItem = cartState.data.getCartItem(),
restroId = cartState.data.restroId,
cartTotalAmount = cartState.data.cartTotalAmount,
cartAddressId = cartState.data.cartAddressId,
cartDeliveryTime = cartState.data.cartDeliveryTime,
cartCookingInstructions = cartState.data.cartCookingInstructions,
cartAppliedOfferId = cartState.data.cartAppliedOfferId,
deliveryPartnerTipAmount = cartState.data.deliveryPartnerTipAmount,
cartDeliveryCharge = cartState.data.cartDeliveryCharge,
cartTax = cartState.data.cartTax,
deliveryInstructionId = cartState.data.deliveryInstructionId,
foodHandlingCharge = cartState.data.foodHandlingCharge,
cartNumberOfItems = cartState.data.cartNumberOfItems,
cartRestroName = cartState.data.cartRestroName
)
}
currentCart = cartState.data
}
is State.Failed -> {
if (cartState.message == "Result null") {
Log.d(
ContentValues.TAG,
"getCartFromCloud: No cart details found in cloud creating new cart"
)
_userCart.update {
it.copy(
cartId = dataStoreRepository.readFileDataStoreValue.first().savedUserId,
cartEmpty = true
)
}
currentCart = CustomerCart(
cartId = dataStoreRepository.readFileDataStoreValue.first().savedUserId,
cartEmpty = true
)
}
}
is State.Loading -> {
Log.d(ContentValues.TAG, "getCartFromCloud: Loading")
}
}
}
} else {
_userCart.value = currentCart
Log.d(ContentValues.TAG, "getCart: $currentCart ")
}
}
I am collecting these state flow from different fragments
every thing works fine except one fragment
here is the code
in on create method
viewLifecycleOwner.lifecycleScope.launch {
viewLifecycleOwner.lifecycle.repeatOnLifecycle(Lifecycle.State.STARTED) {
godCustomerViewModel.currentRestroMenu.collectLatest { menuState ->
Log.d(TAG, "currentRestroMenu ::: mENUSELECT FIRED: ")
when (menuState) {
is State.Success -> {
restroMenu = menuState.data
binding.recyclerView2.hideShimmer()
getCartDetails(restroMenu)
}
is State.Failed -> {
Log.d(TAG, "currentRestroMenu: ")
}
is State.Loading -> {
binding.recyclerView2.showShimmer()
}
}
}
}
}
private fun getCartDetails(restroMenu: Menu) = viewLifecycleOwner.lifecycleScope.launch {
viewLifecycleOwner.lifecycle.repeatOnLifecycle(Lifecycle.State.STARTED) {
godCustomerViewModel.userCart.collectLatest {
if (it.restroId == restroMenu.restroId) {
categoryAdapterRestroDetails.setData(
restroMenu.menuCategories,
it.getCartItem()
)
} else {
categoryAdapterRestroDetails.setData(
restroMenu.menuCategories,
ArrayList()
)
}
}
}
}
I am passing the two collected values to adapter (retro menu and item in cart )
when the fragment is loaded for the first time everything works fine
I have add dish to cart function which updates the value of user cart
fun addDishToCart(dish: Dish) = viewModelScope.launch {
Log.d(ContentValues.TAG, "addDishToCart: view model invoked")
if (currentCart.checkIfCartBelongsToThisRestro(dish.dishRestroId)) {
currentCart.addDishToCart(dish).collect {
Log.d(ContentValues.TAG, "addDishToCartcollect: $currentCart")
_userCart.update {
it.copy(
cartEmpty = currentCart.cartEmpty,
cartItem = currentCart.getCartItem(),
restroId = currentCart.restroId,
cartTotalAmount = currentCart.cartTotalAmount,
cartNumberOfItems = currentCart.cartNumberOfItems,
)
}
}
} else {
// restro Conflict
Log.d(ContentValues.TAG, "addDishToCart: $currentCart")
_restroConflict.value = CartConflict(true, currentCart.cartRestroName, dish)
}
Log.d(ContentValues.TAG, "addDishToCart current cart: ${currentCart.getCartItem()}")
Log.d(ContentValues.TAG, "addDishToCart: user Cart : ${_userCart.value.getCartItem()} ")
}
Which also work fine initially
I also have a button to filter menu to veg non veg
fun filterMenuForVeg(value: Boolean, showAll: Boolean) = viewModelScope.launch {
if (!showAll) {
Log.d(ContentValues.TAG, "filterMenuForVeg: Entered veg :$value")
var filteredMenu = Menu()
filteredMenu.restroId = dataHolderMenuOnSearch.restroId
for (menuCategory in dataHolderMenuOnSearch.menuCategories) {
Log.d(ContentValues.TAG, "filterMenuForVeg: $dataHolderMenuOnSearch ")
for (dish in menuCategory.dishes) {
if (dish.dishVeg == value) {
Log.d(ContentValues.TAG, "found dish with veg $value: ")
var categoryAlreadySaved = false
filteredMenu.menuCategories.filter {
categoryAlreadySaved = it.categoryId == menuCategory.categoryId
true
}
if (!categoryAlreadySaved) {
Log.d(ContentValues.TAG, "menu category not found in filtered list ")
val menuCategoryToAdd = MenuCategories()
menuCategoryToAdd.menuCategoryName = menuCategory.menuCategoryName
menuCategoryToAdd.categoryId = menuCategory.categoryId
menuCategoryToAdd.restroId = menuCategory.restroId
menuCategoryToAdd.dishes.add(dish)
filteredMenu.menuCategories.add(menuCategoryToAdd)
} else {
Log.d(ContentValues.TAG, "menu category found in filtered list ")
filteredMenu.menuCategories.find {
if (it.categoryId == menuCategory.categoryId) {
it.restroId = menuCategory.restroId
it.dishes.add(dish)
}
true
}
}
}
}
}
Log.d(ContentValues.TAG, "filterMenuForVeg : $filteredMenu ")
_currentRestroMenu.value = State.success(filteredMenu)
} else {
// set to all data
_currentRestroMenu.value = State.success(dataHolderMenuOnSearch)
}
When I filter dish for veg or non veg then add dish to cart (Which only changes userCart State flow) the place where I am collecting these state flow
get fired twice
so set data to adapter is getting called twice
What Iam doing wrong
Could you collect the items with onEach instead of collectLatest? It would solve your problem probably.
I want to get the results of my asynchronous function and use them in the fold function. Here's my function that didn't work:
private fun sendOrderStatus(list: List<OrderStatusEntity>) : Single<Boolean> {
return Single.just(
list.fold(true) { initial, item ->
if (!item.isTerminal()) {
val info = OrderStateParameters(
lon = item.orderStatusLon!!,
lat = item.orderStatusLat!!,
datetime = item.orderStatusDate!!
)
val state = OrderState(item.orderId, item.toSend(), info)
return tasksUseCase.sendOrderStatusForWorker(state)
.doOnSuccess { markSent(item) } // side calling
.flatMap {
return#flatMap initial && it.isSuccess // that result should be used in *fold*-function
}
} else // stub result
true
}
)
}
So, I intend to return a Single that will contain the aggregated result of all tasksUseCase.sendOrderStatusForWorker(state) calls.
Thank for any helps!
I am trying to read a numeric data from Cloud Firestore. This number contains many decimals and from Kotlin I only get the first whole number. I have tried to fix it with BigDecimal, but it still doesn't work. Can you help me? Thank you.
fun obtenerDatosBD() {
var readBTC:Int
if (email != null) {
db.collection("users").document(email).get().addOnSuccessListener {
if(it.exists()){
readBTC = it.getDouble("BTC")?.toInt()!!
val test = BigDecimal(readBTC)
println("DATOS: $test")
}else{
//No existen datos
db.collection("users").document(email).set(
hashMapOf(
"Saldo" to "0,00",
"BTC" to 0.000000,
"Provider" to provider
)
)
}
}
}
}
You are losing all the decimal points here:
it.getDouble("BTC")?.toInt()!!
You are reading it as Double and then making it an Int. Instead you should try and read it as a String and give that to the BigDecimal constructor.
fun obtenerDatosBD() {
var readBTC: String //Int has no decimal places
if (email != null) {
db.collection("users").document(email).get().addOnSuccessListener {
if (it.exists()) {
readBTC = it.getString("BTC") //or `it.get("BTC") as? String?` or something, I don't know what type of object `it` is
//something to do if readBTC is null, like a return, or have the non existence message in another fun and call it from here as well.
val test = BigDecimal(readBTC)
println("DATOS: $test")
} else {
//No existen datos
db.collection("users").document(email).set(
hashMapOf(
"Saldo" to "0,00",
"BTC" to 0.000000,
"Provider" to provider
)
)
}
}
}
}
fun obtenerDatosBD() {
var readBTC:String
if (email != null) {
db.collection("users").document(email).get().addOnSuccessListener {
if(it.exists()){
readBTC = it.getString("BTC").toString()
val test = BigDecimal(readBTC)
val testInt: Double = test.toDouble()
println("DATOS: $test + $testInt")
}else{
//No existen datos
db.collection("users").document(email).set(
hashMapOf(
"Saldo" to "0,00",
"BTC" to "0.000000",
"Provider" to provider
)
)
}
}
}
}
I have an RecycleView that contains ImageViews and my question is how can i move the snap to be on the left side of the RecycleView instead of the center?
When i move the ImageViews they get snapped in the center and I can move them to the left or right inside that "snap window" by overriding the CalculateDistanceToFinalSnap method. I think I would now need to move that "snap window" to the left side of the RecycleView but I don't know how, or maybe there is another way, please help.
Here is a image of my problem, maybe it will help you to understand more clearly:
image
#Jessie Zhang -MSFT's solution works for me. The code was a little oddly formatted and I had some difficulty bringing it over. Here is the same solution (for a horizontal snap only) in Kotlin.
class StartSnapHelper: LinearSnapHelper() {
override fun calculateDistanceToFinalSnap(layoutManager: RecyclerView.LayoutManager, targetView: View): IntArray? {
return if (layoutManager.canScrollHorizontally()) {
val outer = mutableListOf<Int>()
outer.add(distanceToStart(targetView, getHorizontalHelper(layoutManager)))
outer.add(0)
outer.toIntArray()
} else {
super.calculateDistanceToFinalSnap(layoutManager, targetView)
}
}
override fun findSnapView(layoutManager: RecyclerView.LayoutManager?): View? {
return if (layoutManager is LinearLayoutManager) {
if (layoutManager.canScrollHorizontally()) {
getStartView(layoutManager, getHorizontalHelper(layoutManager))
} else {
super.findSnapView(layoutManager)
}
} else {
super.findSnapView(layoutManager)
}
}
private fun distanceToStart(targetView: View, helper: OrientationHelper): Int {
return helper.getDecoratedStart(targetView) - helper.startAfterPadding
}
private fun getStartView(layoutManager: RecyclerView.LayoutManager, orientationHelper: OrientationHelper): View? {
val firstChild = (layoutManager as LinearLayoutManager).findFirstVisibleItemPosition()
val isLastItem = (layoutManager.findLastCompletelyVisibleItemPosition() == layoutManager.itemCount - 1)
if (firstChild == RecyclerView.NO_POSITION || isLastItem) {
return null
}
val child = layoutManager.findViewByPosition(firstChild)
return if (orientationHelper.getDecoratedEnd(child) >= orientationHelper.getDecoratedMeasurement(child) / 2
&& orientationHelper.getDecoratedEnd(child) > 0) {
child;
} else {
if (layoutManager.findFirstCompletelyVisibleItemPosition() == layoutManager.itemCount -1) {
null
} else {
layoutManager.findViewByPosition(firstChild + 1)
}
}
}
private fun getHorizontalHelper(layoutManager: RecyclerView.LayoutManager): OrientationHelper {
return OrientationHelper.createHorizontalHelper(layoutManager)
}
}
I have achieved this function ,we juse need to create a class and extent class LinearSnapHelper and override method CalculateDistanceToFinalSnap and FindSnapView. You can check out the full demo here .
The main code is as follows:
public class StartSnapHelper: LinearSnapHelper
{
private OrientationHelper mVerticalHelper, mHorizontalHelper;
public StartSnapHelper()
{
}
public override void AttachToRecyclerView(RecyclerView recyclerView)
{
base.AttachToRecyclerView(recyclerView);
}
public override int[] CalculateDistanceToFinalSnap(RecyclerView.LayoutManager layoutManager, View targetView)
{
//return base.CalculateDistanceToFinalSnap(layoutManager, targetView);
int[] outer = new int[2];
if (layoutManager.CanScrollHorizontally())
{
outer[0] = distanceToStart(targetView, getHorizontalHelper(layoutManager));
} else {
outer[0] = 0;
}
if (layoutManager.CanScrollVertically()) {
outer[1] = distanceToStart(targetView, getVerticalHelper(layoutManager));
} else {
outer[1] = 0;
}
return outer;
}
private int distanceToStart(View targetView, OrientationHelper helper)
{
return helper.GetDecoratedStart(targetView) - helper.StartAfterPadding;
}
public override View FindSnapView(RecyclerView.LayoutManager layoutManager)
{
if (layoutManager is LinearLayoutManager) {
if (layoutManager.CanScrollHorizontally())
{
return getStartView(layoutManager, getHorizontalHelper(layoutManager));
}
else
{
return getStartView(layoutManager, getVerticalHelper(layoutManager));
}
}
return base.FindSnapView(layoutManager);
}
private View getStartView(RecyclerView.LayoutManager layoutManager,
OrientationHelper helper)
{
if (layoutManager is LinearLayoutManager) {
int firstChild = ((LinearLayoutManager)layoutManager).FindFirstVisibleItemPosition();
bool isLastItem = ((LinearLayoutManager)layoutManager)
.FindLastCompletelyVisibleItemPosition()
== layoutManager.ItemCount - 1;
if (firstChild == RecyclerView.NoPosition || isLastItem)
{
return null;
}
View child = layoutManager.FindViewByPosition(firstChild);
if (helper.GetDecoratedEnd(child) >= helper.GetDecoratedMeasurement(child) / 2
&& helper.GetDecoratedEnd(child) > 0)
{
return child;
}
else
{
if (((LinearLayoutManager)layoutManager).FindLastCompletelyVisibleItemPosition()
== layoutManager.ItemCount - 1)
{
return null;
}
else
{
return layoutManager.FindViewByPosition(firstChild + 1);
}
}
}
return base.FindSnapView(layoutManager);
}
private OrientationHelper getVerticalHelper(RecyclerView.LayoutManager layoutManager)
{
if (mVerticalHelper == null)
{
mVerticalHelper = OrientationHelper.CreateVerticalHelper(layoutManager);
}
return mVerticalHelper;
}
private OrientationHelper getHorizontalHelper(RecyclerView.LayoutManager layoutManager)
{
if (mHorizontalHelper == null)
{
mHorizontalHelper = OrientationHelper.CreateHorizontalHelper(layoutManager);
}
return mHorizontalHelper;
}
}
And use like this:
SnapHelper snapHelperStart = new StartSnapHelper();
snapHelperStart.AttachToRecyclerView(recyclerView);
I have two arrays. But when I change second - first change too.
I tried
.clone()
.copyOf()
but it didn't work for me.
object MatrixObject {
var table: Array<Array<Int>>? = null
fun randOf(n: Int) {
table= Array(n, { Array(n, { Random().nextInt(100 - 0) + 0 }) })
}
var tableF: Array<Array<Int>>? = null
get() {
if (field==null)
factorization()
return field
}
fun factorization() {
tableF = table!!
... //here I change elements of tableF
}
}
I tried
for(row in 0 until table!!.size)
tableF!![row] = Arrays.copyOf(table!![row], table!![row].size)
and
for(row in 0 until table!!.size)
tableF!![row] = table!![row].clone() // and copyOf()
but it still doesn't work.
I found the solution.I initialized the array.
tableF= Array(table!!.size, { Array(table!!.size, {0}) })
for(row in 0 until table!!.size)
tableF!![row] = table!![row].clone()