Sorry, I'm bad in English. I'm beginner in Android Studio.
I building same CREATE, UPDATE AND DELETE application in Android Studio, using custom RecycleView. But, I confused how to get row data when recycleview item clicked.
Can I get visible text in RecycleView item or not? Or can I get that data directly from SQLite.
How to get SQLite ID from this adapter?
package gh.alwathan.sipinsyar
import android.support.v7.widget.PopupMenu
import android.support.v7.widget.RecyclerView
import android.view.*
import android.widget.TextView
import android.widget.Toast
class NasabahAdapter(val userList: ArrayList<Nasabah>) : RecyclerView.Adapter<NasabahAdapter.ViewHolder>() {
//this method is returning the view for each item in the list
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): NasabahAdapter.ViewHolder {
val v = LayoutInflater.from(parent.context).inflate(R.layout.list_item_nasabah, parent, false)
return ViewHolder(v)
}
//this method is binding the data on the list
override fun onBindViewHolder(holder: NasabahAdapter.ViewHolder, position: Int) {
holder.bindItems(userList[position])
holder.itemView.setOnLongClickListener {
//holder.nametxt.setText(players.get(position).getName());
//creating a popup menu
val popup = PopupMenu(holder.itemView.getContext(), holder.itemView, Gravity.RIGHT)
//inflating menu from xml resource
popup.inflate(R.menu.nasabah_item)
//adding click listener
popup.setOnMenuItemClickListener(PopupMenu.OnMenuItemClickListener { item: MenuItem? ->
when (item!!.itemId) {
R.id.nasabah_id-> {
// GET SQLITE ID FROM HERE
}
}
true
})
//displaying the popup
popup.show()
true
}
}
//this method is giving the size of the list
override fun getItemCount(): Int {
return userList.size
}
//the class is hodling the list view
class ViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
fun bindItems(user: Nasabah) {
val textViewName = itemView.findViewById(R.id.nasabah_id) as TextView
val textViewLastName = itemView.findViewById(R.id.nasabah_nama) as TextView
textViewName.text = user.id
textViewLastName.text = user.nama
}
}
}
data class Nasabah(val id: String, val nama: String)
Related
I have a spinner with an array adapter. The spinner is populated inside a fragment onCreateView().
spinner.setSelection(0)
spinner.onItemSelectedListener =
object : AdapterView.OnItemSelectedListener {
override fun onItemSelected(parent: AdapterView<*>, view: View?, pos: Int, id: Long) {
}
override fun onNothingSelected(var1: AdapterView<*>?) {
}
}
Whenever I get back to the fragment and the spinner is created, the last selected item is selected when onItemSelected() is called automatically and ignoring the spinner.setSelection(0) call.
I have put many logs to see what is going, but I cannot understand why the lately selected item is the one being selected by default and not the one at position 0.
I solved the issue by setting a click listener on the drop down view and basically do the same stuff I was doing with the OnItemSelectedListener.
override fun getDropDownView(position: Int, convertView: View?, parent: ViewGroup): View {
val binding = SpinnerItemChartDropdownBinding.inflate(
LayoutInflater.from(parent.context),
parent,
false
)
val item = getItem(position)
val root = binding.root
bindDropdown(root, item)
binding.setClickListener {
listener.onChartRangeSelected(item)
}
return root
}
One important stuff. You need to do something like this, to dismiss the drop down view after an item has been selected:
fun hideSpinnerDropDown(spinner: Spinner) {
try {
val method: Method = Spinner::class.java.getDeclaredMethod("onDetachedFromWindow")
method.isAccessible = true
method.invoke(spinner)
} catch (e: java.lang.Exception) {
e.printStackTrace()
}
}
Im working on a quizgame and i want to store some ids in a MutableLiveData-arraylist. Therfore i made a function to loop all my documents in de database and add each ID to the arraylist. BUT the outcome is always null. I don't see where i go wrong?
I'm working with a MVVM-structure
GameViewModel:
class GameViewModel : ViewModel() {
// database instance
val db = FirebaseFirestore.getInstance()
// the current category
private val _category = MutableLiveData<String>()
val category: LiveData<String>
get() = _category
// the list of questionIds of the selected category
private val _questionIdsArray = MutableLiveData<ArrayList<Long>>()
val questionIdsArray: LiveData<ArrayList<Long>>
get() = _questionIdsArray
// the current question
private val _question = MutableLiveData<String>()
val question: LiveData<String>
get() = _question
/**
* Set Current Category
*/
fun SetCategory (categoryName: String){
_category.value = categoryName
}
/**
* Get the list of QuestionIds
*/
fun GetListQuestionIds() {
db.collection("questions")
.whereEqualTo("category", "$_category")
.get()
.addOnSuccessListener { documents ->
for (document in documents) {
_questionIdsArray.value?.add(document.data["questionid"] as Long)
Log.d("GetSize","${_questionIdsArray.value?.size}")
}
Log.d("GetSize2","${_questionIdsArray.value?.size}")
}
.addOnFailureListener { exception ->
Log.w("errorforloop", "Error getting documents: ", exception)
}
}
/**
* Get a Question
*/
fun GetQuizQuestion() {
Log.d("retro","${_questionIdsArray.value?.size}")
db.collection("questions")
.whereEqualTo("category", "$_category")
.whereEqualTo("questionid", "${_questionIdsArray.value?.get(0)}")
.get()
.addOnSuccessListener { documents ->
for (document in documents) {
_question.value = document.data["question"].toString()
}
}
.addOnFailureListener { exception ->
Log.w("err", "Error getting documents: ", exception)
}
}
GAMEFRAGMENT:
class GameFragment : Fragment() {
private lateinit var viewModel: GameViewModel
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val binding = FragmentGameBinding.inflate(inflater)
// Get the viewModel
viewModel = ViewModelProvider(this).get(GameViewModel::class.java)
binding.lifecycleOwner = this
// Set the viewModel for DataBinding - this allows the bound layout access to all of the data in the VieWModel
binding.gameviewModel = viewModel
//arguments passed
val selectedCategory = arguments?.getString("selectedCategory")!!
//set current category so that the viewModel can use it
viewModel.SetCategory(selectedCategory)
viewModel.GetListQuestionIds()
viewModel.GetQuizQuestion()
return binding.root
}
If someone can enlighten me ...
Your Problem
You're not initializing the array. This is your code:
// the list of questionIds of the selected category
private val _questionIdsArray = MutableLiveData<ArrayList<Long>>()
val questionIdsArray: LiveData<ArrayList<Long>>
get() = _questionIdsArray
This declares a MutableLiveData of type ArrayList<Long>, but does not initialize it so its value defaults to null.
In your for loop you conditionally add items:
_questionIdsArray.value?.add(document.data["questionid"] as Long)
But of course value was never initialized so it's null so add is no-op (does nothing).
The Solution
Just ensure you initialize the live data object at some point.
You could do this inline in the declaration:
// the list of questionIds of the selected category
private val _questionIdsArray = MutableLiveData<ArrayList<Long>>(arrayListOf())
val questionIdsArray: LiveData<ArrayList<Long>>
get() = _questionIdsArray
Or during your attempt to populate the list:
.addOnSuccessListener { documents ->
val idsArray = arrayListOf<Long>() // Non-null list to add to
for (document in documents) {
idsArray.add(document.data["questionid"] as Long)
Log.d("GetSize","${idsArray.size}")
}
_questionIdsArray.value = idsArray // Now set live data with a valid list
Log.d("GetSize2","${_questionIdsArray.value?.size}")
}
Hey I am very new to tornadofx struggeling with async loading of data for the treeview. I am loading categories from a rest endpoint, which I want to show in there.
It seems like there's no direct data binding to the children.
when using 'bindChildren' I can provide the observable list, but I have to convert them into Node's. which then would make the populate block kind of obsolete.
What's the recommended way of doing this? I cannot find anything about this.
// Category
interface Category<T : Category<T>> {
val id: String
val name: String
val subcategories: List<T>?
}
//default category:
class DefaultCategory(override val name: String) : Category<DefaultCategory> {
override val id: String = "default"
override val subcategories: List<DefaultCategory>? = null
}
//ViewModel
class CategoryViewModel : ViewModel() {
val sourceProperty = SimpleListProperty<Category<*>>()
fun loadData() {
// load items for treeview into 'newItems'
sourceProperty.value = newItems
}
}
// TreeViewFactoryMethod
private fun createTreeView(
listProperty: SimpleListProperty<Category<*>>
): TreeView<Category<*>> {
return treeview {
root = TreeItem(DefaultCategory("Categories"))
isShowRoot = false
root.isExpanded = true
root.children.forEach { it.isExpanded = true }
cellFormat { text = it.name }
populate { parent ->
when (parent) {
root -> listProperty.value
else -> parent.value.subcategories
}
}
}
}
Assuming that on a button click I call viewmodel.loadData(), I would expect the TreeView to update as soon as there's some new data. (If I would've found a way to bind)
I've never had to use bindChildren for TornadoFX before and your use of async isn't very relevant to what I think is your primary problem. So, admittedly, this question kind of confused me at first but I'm guessing you're just wondering why the list isn't appearing in your TreeView? I've made a test example with changes to make it work.
// Category
interface Category<T : Category<T>> {
val id: String
val name: String
val subcategories: List<T>?
}
//default category:
class DefaultCategory(override val name: String) : Category<DefaultCategory> {
override val id: String = "default"
override val subcategories: List<DefaultCategory>? = null
}
//Just a dummy category
class ChildCategory(override val name: String) : Category<ChildCategory> {
override val id = name
override val subcategories: List<ChildCategory>? = null
}
//ViewModel
class CategoryViewModel : ViewModel() {
//filled with dummy data
val sourceProperty = SimpleListProperty<Category<*>>(listOf(
ChildCategory("Categorya"),
ChildCategory("Categoryb"),
ChildCategory("Categoryc"),
ChildCategory("Categoryd")
).asObservable())
fun loadData() {
sourceProperty.asyncItems {
//items grabbed somehow
listOf(
ChildCategory("Category1"),
ChildCategory("Category2"),
ChildCategory("Category3"),
ChildCategory("Category4")
).asObservable()
}
}
}
class TestView : View() {
val model: CategoryViewModel by inject()
override val root = vbox(10) {
button("Refresh Items").action {
model.loadData()
}
add(createTreeView(model.sourceProperty))
}
// TreeViewFactoryMethod
private fun createTreeView(
listProperty: SimpleListProperty<Category<*>>
): TreeView<Category<*>> {
return treeview {
root = TreeItem(DefaultCategory("Categories"))
isShowRoot = false
root.isExpanded = true
root.children.forEach { it.isExpanded = true }
cellFormat { text = it.name }
populate { parent ->
when (parent) {
root -> listProperty
else -> parent.value.subcategories
}
}
}
}
}
There are 2 important distinctions that are important.
1. The more relevant distinction is that inside the populate block, root -> listProperty is used instead of root.listProperty.value. This will make your list appear. The reason is that a SimpleListProperty is not a list, it holds a list. So, yes, passing in a plain list is perfectly valid (like how you passed in the value of the list property). But now that means the tree view isn't listening to your property, just the list you passed in. With that in mind, I would be considerate over the categories' subcategory lists are implemented as well.
2. Secondly, notice the use of asyncItems in the ViewModel. This will perform whatever task asynchronously, then set the items to list on success. You can even add fail or cancel blocks to it. I'd recommend using this, as long/intensive operations aren't supposed to be performed on the UI thread.
I am trying to get a class to have a property bound to another class's list property, where the 1st property is derived from a summarizing calculation over the objects in the list. The code below is a simplified version of my production code. (The production code is doing a summary over DateTime objects -- the essential part of the code below is the binding between a list and an object property (here, it is a String for simplicity).)
I have tried various things. One approach was using addListener on the list in the Summary class below but I was running into weird bugs with the listener callback making updates on the Summary object. After doing a bunch of reading I think that a binding between the summary string and the list is more appropriate but I don't know exactly how to hook up the binding to the property?
package com.example.demo.view
import javafx.beans.Observable
import javafx.beans.binding.StringBinding
import javafx.beans.property.SimpleIntegerProperty
import javafx.beans.property.SimpleListProperty
import javafx.beans.property.SimpleStringProperty
import javafx.collections.FXCollections
import tornadofx.View
import tornadofx.button
import tornadofx.label
import tornadofx.vbox
class Thing(x: Int) {
val xProperty = SimpleIntegerProperty(x)
val yProperty = SimpleStringProperty("xyz")
}
class Collection {
private var things = FXCollections.observableList(mutableListOf<Thing>()) {
arrayOf<Observable>(it.xProperty)
}
val thingsProperty = SimpleListProperty<Thing>(things)
fun addThing(thing: Thing) {
things.add(thing)
}
}
class Summary(var collection: Collection) {
val summaryBinding = object : StringBinding() {
// The real code is more practical but
// this is just a minimal example.
override fun computeValue(): String {
val sum = collection.thingsProperty.value
.map { it.xProperty.value }
.fold(0, { total, next -> total + next })
return "There are $sum things."
}
}
// How to make this property update when collection changes?
val summaryProperty = SimpleStringProperty("There are ? things.")
}
class MainView : View() {
val summary = Summary(Collection())
override val root = vbox {
label(summary.summaryProperty)
button("Add Thing") {
summary.collection.addThing(Thing(5))
}
}
}
Keep in mind that I made this answer based on your minimal example:
class Thing(x: Int) {
val xProperty = SimpleIntegerProperty(x)
var x by xProperty
val yProperty = SimpleStringProperty("xyz")
var y by yProperty
}
class MainView : View() {
val things = FXCollections.observableList(mutableListOf<Thing>()) {
arrayOf<Observable>(it.xProperty)
}
val thingsProperty = SimpleListProperty<Thing>(things)
val totalBinding = integerBinding(listProperty) {
value.map { it.x }.fold(0, { total, next -> total + next })
}
val phraseBinding = stringBinding(totalBinding) { "There are $value things." }
override val root = vbox {
label(phraseBinding)
button("Add Thing") {
action {
list.add(Thing(5))
}
}
}
}
I removed your other classes because I didn't see a reason for them based on the example. If the collection class has more functionality than holding a list property in your real project, then add just add it back in. If not, then there's no reason to give a list its own class. The summary class is really just two bindings (or one if you have no need to separate the total from the phrase). I don't see the need to give them their own class either unless you plan on using them in multiple views.
I think your biggest problem is that you didn't wrap your button's action in action {}. So your code just added a Thing(5) on init and had no action set.
P.S. The var x by xProperty stuff will only work if you import tornadofx.* for that file.
I have a small start on a SwiftUI app. I'm trying to connect a button to an action in an NSView that I've added to the body of the SwiftUI.
I can't figure out how to reference the DrawingView inside the action of the button so that I can call the toggleDrawingType action. I've found no developer documentation that gives any hints as to how to go about this.
------- ContentView.swift -------
import SwiftUI
struct ContentView : View {
var body: some View {
VStack {
HStack {
Text("Hello")
Image("LineTool")
Button(action: {}) {
Image("CenterCircleTool")
}
}
DrawingView()
}
}
}
-------- DrawingView.swift --------
import SwiftUI
public struct DrawingView: NSViewRepresentable {
public typealias NSViewType = DrawingViewImplementation
public func makeNSView(context: NSViewRepresentableContext<DrawingView>) -> DrawingViewImplementation {
return DrawingViewImplementation()
}
public func updateNSView(_ nsView: DrawingViewImplementation, context: NSViewRepresentableContext<DrawingView>) {
nsView.setNeedsDisplay(nsView.bounds)
}
}
enum DrawingType {
case Rect
case Circle
}
public class DrawingViewImplementation: NSView {
var currentType = DrawingType.Rect
override public func draw(_ dirtyRect: NSRect) {
super.draw(dirtyRect)
NSColor.blue.set()
switch currentType {
case .Rect:
NSRect(x: 100, y: 100, width: 100, height: 100).frame()
case .Circle:
NSBezierPath(ovalIn: NSRect(x: 100, y: 100, width: 100, height: 100)).stroke()
}
}
#IBAction func toggleDrawingType(sender: Any) {
switch currentType {
case .Rect:
currentType = .Circle
case .Circle:
currentType = .Rect
}
setNeedsDisplay(bounds)
}
public override func mouseDown(with event: NSEvent) {
toggleDrawingType(sender: self)
}
}
I had the same problem and found a solution in the organisation of the code.
The basic problem is that a structure following the NSViewRepresentable protocol does by itself not hand out a reference to its underlying NSView.
The solution is to introduce an object which is available at the time of creation of the ViewRepresentable structure. Its reference to the view is set at the time of creation of the view.
I my eyes this is part of the bigger picture that with SwiftUI views view controllers are not any longer present. SwiftUI views depend directly on the model objects (via the #ObservableObject or #EnvironmentObject variable). Hence the model object tends to cary the functionality which before the view controller carried (or the View structure carries this functionality directly).
I hand in the model object into the initialiser of the ViewRepresentable and set a weak reference within the model object to the view created. Like this the content object is the omnipresent entity - within the ViewRepresentable and within the SwiftUI View structure.