Develop Reference

How to Intialize the Binding Properties in the Fragment to Make Two Way Data Binding Work

So I'm doing a project and I'm completely lost. I have seen how to do data binding with TextViews but I am being asked to do it with EditText Views with Two Way Data Binding. I got up to here so far with it.
The XML File.
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools">
<data>
<variable
name="myShoe"
type="com.udacity.shoestore.product.Shoe" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorPrimary">
<TextView
android:id="#+id/title_detail_view"
style="#style/title_style"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="80dp"
android:text="#string/add_shoe_title"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<EditText
android:id="#+id/shoe_name"
style="#style/login_style"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginEnd="16dp"
android:ems="10"
android:hint="#string/shoe_name_string"
android:inputType="text"
android:textSize="30sp"
android:text="#={myShoe.name}"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/title_detail_view" />
<EditText
android:id="#+id/shoe_size"
style="#style/login_style"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:ems="10"
android:hint="#string/size_string"
android:inputType="number|numberDecimal"
android:textSize="15sp"
android:text="#={myShoe.size}"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/shoe_name" />
<EditText
android:id="#+id/company_name"
style="#style/login_style"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:ems="10"
android:hint="#string/company_string"
android:inputType="text"
android:textSize="15sp"
android:text="#={myShoe.company}"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/shoe_size" />
<EditText
android:id="#+id/shoe_description"
style="#style/login_style"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:ems="10"
android:hint="#string/description_string"
android:inputType="text"
android:textSize="15sp"
android:text="#={myShoe.description}"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/company_name" />
<Button
android:id="#+id/cancel_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:backgroundTint="#color/colorPrimaryDark"
android:text="#string/cancel_string"
android:textColor="#android:color/white"
app:layout_constraintBaseline_toBaselineOf="#+id/savee_button"
app:layout_constraintEnd_toStartOf="#+id/savee_button"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="#+id/savee_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginEnd="88dp"
android:backgroundTint="#color/colorPrimaryDark"
android:text="#string/save_string"
android:textColor="#android:color/white"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toBottomOf="#+id/shoe_description" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
I was told to implement it to a fragment and it should work. But I'm not sure how. Here's the fragment
class ShoeDetailsFragment : Fragment() {
private val viewModel: ActivityViewModel by activityViewModels()
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
val binding: FragmentShoeDetailsBinding = DataBindingUtil.inflate(
inflater,
R.layout.fragment_shoe_details,
container, false
)
//initializing the button and clearing the views once canceled
binding.cancelButton.setOnClickListener { v: View ->
v.findNavController().navigateUp()
binding.shoeName.text.clear()
binding.shoeSize.text.clear()
binding.companyName.text.clear()
binding.shoeDescription.text.clear()
}
//initializing the button and saving the info to transfer to the shoeList
binding.saveeButton.setOnClickListener { v: View ->
v.findNavController().navigateUp()
val name = shoe_name.text.toString()
val size = shoe_size.text.toString()
val brand = company_name.text.toString()
val details = shoe_description.text.toString()
viewModel.addShoe(name, size, brand, details)
}
return binding.root
}
}
I am open to any ideas to initialize binding properties so i can use it in both the layout and the fragment. Or am I looking at this the wrong way?
P.S. The XML File is being represented in this fragment

I also did this project for my NanoDegree.
Inside my ViewModel I created 3 variables for each EditText:
MutableLiveData - to update the value inside the viewModel
LiveData to expose value outside viewModel e.g. in a fragment (you won't really need this)
Public Variable to monitor value of MutableLiveData and expose this to your xml thus achieving the 2-Way Binding.
Then I and would create a Shared ViewModel to share data between ShoeDetailsFragment and ShoeListingFragment .
Inside the SharedViewModel
I created 3 variables for each EditText (this is just the first 2 Edittexts):
class MySharedViewModel : ViewModel() {
private val _name = MutableLiveData<String>()
val name: LiveData<String>
get() = _name
var edShoeName = ""
private val _size = MutableLiveData<Double>()
val size: LiveData<Double>
get() = _size
var edSize = ""
......}
For the xml I did exactly what you have done but used the 3rd variable for the 2-Way Data Binding:
<EditText
android:id="#+id/shoe_name"
style="#style/login_style"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginEnd="16dp"
android:ems="10"
android:hint="#string/shoe_name_string"
android:inputType="text"
android:textSize="30sp"
android:text="#={mySharedViewModel.edShoeName}"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/title_detail_view" />
<EditText
android:id="#+id/shoe_size"
style="#style/login_style"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:ems="10"
android:hint="#string/size_string"
android:inputType="number|numberDecimal"
android:textSize="15sp"
android:text="#={mySharedViewModel.edCompany}"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/shoe_name" />
I have seen you have included this line of code on your ShoeDetailFragment code:
binding.saveeButton.setOnClickListener { v: View -> ....}
In my case I did it inside SharedViewModel instead:
fun onSaveButtonClick() {
//check value entered for size and set it to 0 if blank
if (edSize == "") {
edSize = "0"
}
//update MutableLiveData with values read live from the EditText
_name.value = edShoeName
_size.value = edSize.toDouble()
//save shoeObject to the _shoeList MutableLiveData
_shoeList.value?.add(Shoe(edShoeName, edSize.toDouble(), edCompany, edDescription))
}
Using DataBinding I moved the onClick bit to xml:
<Button
android:id="#+id/buttonSave"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="75dp"
android:layout_marginBottom="75dp"
android:background="#drawable/custom_button_background"
android:onClick="#{()->sharedViewModel.onSaveButtonClick()}"
You can also refer to my project.

java.lang.ClassCastException: java.lang.Integer cannot be cast to android.widget.ImageButton

So I'm fairly new to Kotlin.
I am trying to create an onClickListener on an image button to open the share interface, so that the particular video from the recyclerView can be shared via SMS, etc.
I followed various tutorials on how to do this as I am trying to execute this within a fragment, and the app just keeps crashing when I try to open the fragment in question.
I get the following error
java.lang.ClassCastException: java.lang.Integer cannot be cast to android.widget.ImageButton
Here is what my fragment code looks like:
SearchFragment.kt
class SearchFragment : Fragment(), View.OnClickListener
{
private var layoutManager: RecyclerView.LayoutManager? = null
private var adapter: RecyclerView.Adapter<ClipAdapter.ViewHolder>? = null
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View
{
val rootView = inflater.inflate(R.layout.fragment_search, container, false)
loadData()
return rootView
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?)
{
val shareBtn = view.findViewById<ImageButton>(R.id.button_to_share)
shareBtn.setOnClickListener(this)
}
private fun loadData()
{
val service = TwitchServiceBuilder.buildService(TwitchService::class.java)
val requestCall = service.getClips("anerdfails")
requestCall.enqueue(object : Callback<List<Clip>>
{
override fun onResponse(
call: Call<List<Clip>>,
response: Response<List<Clip>>
)
{
if (response.isSuccessful)
{
//process data
recyclerView.layoutManager = GridLayoutManager(activity, 2)
recyclerView.adapter = ClipAdapter(response.body()!!)
} else
{
//output alert
AlertDialog.Builder(activity!!)
.setTitle("API error")
.setMessage("Response, but something went wrong ${response.message()}")
.setPositiveButton(android.R.string.ok) { _, _ -> }
.setIcon(android.R.drawable.ic_dialog_alert)
.show()
}
}
override fun onFailure(call: Call<List<Clip>>, t: Throwable)
{
//process failure
AlertDialog.Builder(activity!!)
.setTitle("API error")
.setMessage("No response, and something went wrong $t")
.setPositiveButton(android.R.string.ok) { _, _ -> }
.setIcon(android.R.drawable.ic_dialog_alert)
.show()
}
})
}
override fun onClick(v: View?)
{
Toast.makeText(activity, "Its toast!", Toast.LENGTH_SHORT).show()
}
}
And here are my 2 layouts for the RecyclerView:
fragment_search.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingStart="15dp"
android:paddingTop="?attr/actionBarSize"
android:paddingEnd="15dp"
tools:context=".ui.search.SearchFragment">
<androidx.appcompat.widget.SearchView
android:background="#drawable/search_bar"
android:id="#+id/clipSearch"
android:layout_width="fill_parent"
android:layout_height="50dp"
android:layout_marginTop="15dp"
android:layout_marginBottom="5dp"
android:focusable="true"
android:focusableInTouchMode="true"
app:layout_constraintBottom_toTopOf="#+id/recyclerView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.recyclerview.widget.RecyclerView
android:id="#+id/recyclerView"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginTop="15dp"
android:layout_marginBottom="75dp"
android:scrollbars="vertical"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/clipSearch" />
</androidx.constraintlayout.widget.ConstraintLayout>
clip_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
tools:context=".ui.search.SearchFragment">
<VideoView
android:id="#+id/videoClip"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="8dp"
android:layout_marginTop="16dp"
android:layout_marginEnd="8dp"
app:layout_constraintDimensionRatio="w,2:3"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/txtTitle"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:text="TextView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/videoClip"
tools:ignore="HardcodedText" />
<TextView
android:id="#+id/txtChannel"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:text="TextView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/txtTitle"
tools:ignore="HardcodedText" />
<TextView
android:id="#+id/txtGame"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:text="TextView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/txtChannel"
tools:ignore="HardcodedText" />
<TextView
android:id="#+id/txtViews"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:text="TextView"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/txtGame"
tools:ignore="HardcodedText" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="30dp"
android:orientation="horizontal"
android:weightSum="2"
android:layout_marginTop="15dp"
app:layout_constraintTop_toBottomOf="#+id/txtViews">
<ImageButton
android:id="#+id/favouriteButton"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#null"
android:scaleType="fitCenter"
android:src="#drawable/ic_baseline_favorite_border_24" />
<ImageButton
android:id="#+id/button_to_share"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:background="#null"
android:scaleType="fitCenter"
android:src="#drawable/ic_baseline_share_24" />
</LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>
Seems like a simple mistake on my part, but I'm pulling my hair out trying to work out what I've done wrong to cause the error on loading.
Any help would be appreciated.

I see you're trying to find the button "ShareBtn" inside the fragment which is totally wrong.
the "ShareBtn" doesn't belong to the fragment, it belongs to the viewHolder which you have created inside "ClipAdapter"
What you need to do is creating an interface inside "ClipAdapter" and create an object from it inside the Adapter
then call the method which is should the clickListener delegates the click to it
lastly, you should implement it inside the fragment and put whatever logic you want
This link will help you implement it

You are casting ID of view which is an Integer to ImageButton which is a View in this line
val shareBtn = R.id.button_to_share as ImageButton
You should use this instead
val shareBtn = findViewById<ImageButton>(R.id.button_to_share)
UPDATE
Also you should find views after fragment view got created. It means you should call `findViewById` inside `onViewCreated` and not inside `onCreateView`. If you try to find views before view of fragment gets created then you get `NullPointerException` since there is no view yet.

Custom TextInputLayout gets wrong values set on back pressed

In my app I'm using custom view containing a TextInputLayout with the following code:
<?xml version="1.0" encoding="utf-8"?>
<androidx.appcompat.widget.LinearLayoutCompat xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.google.android.material.textfield.TextInputLayout
android:id="#+id/input_layout"
style="#style/UbiInput2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="-"
android:orientation="horizontal"
app:boxBackgroundColor="#color/white">
<com.google.android.material.textfield.TextInputEditText
android:id="#+id/input_value"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:inputType="textPersonName" />
</com.google.android.material.textfield.TextInputLayout>
</androidx.appcompat.widget.LinearLayoutCompat>
And the kotlin
class TextInputView(context: Context, attrs: AttributeSet?) : LinearLayout(context, attrs) {
var errorMessage: String? = ""
init {
inflate(context, R.layout.text_input_view, this)
val attributes = context.obtainStyledAttributes(attrs, R.styleable.TextInputView)
val inputLayout = findViewById<TextInputLayout>(R.id.input_layout)
val inputValue = findViewById<TextInputEditText>(R.id.input_value)
inputLayout.hint = attributes.getString(R.styleable.TextInputView_hint)
inputValue.hint = attributes.getString(R.styleable.TextInputView_placeholderText)
inputLayout.isExpandedHintEnabled =
attributes.getBoolean(R.styleable.TextInputView_expandedHintEnabled, true)
errorMessage = attributes.getString(R.styleable.TextInputView_errorMessage)
inputLayout.isHelperTextEnabled = false
inputValue.inputType =
attributes.getInt(
R.styleable.TextInputView_android_inputType,
InputType.TYPE_CLASS_TEXT
)
if (attributes.hasValue(R.styleable.TextInputView_android_maxLength)) {
inputValue.filters += InputFilter.LengthFilter(
attributes.getInt(
R.styleable.TextInputView_android_maxLength,
100
)
)
}
inputValue.gravity =
attributes.getInt(R.styleable.TextInputView_android_gravity, Gravity.START)
if (attributes.getBoolean(R.styleable.TextInputView_android_gravity, false)) {
inputLayout.helperText = attributes.getString(R.styleable.TextInputView_helperText)
}
if (attributes.getBoolean(R.styleable.TextInputView_helperTextEnabled, false)) {
inputLayout.isHelperTextEnabled = true
inputLayout.helperText = attributes.getString(R.styleable.TextInputView_helperText)
}
inputLayout.startIconDrawable =
attributes.getDrawable(R.styleable.TextInputView_startIconDrawable)
attributes.recycle()
}
}
#BindingAdapter("textValue")
fun TextInputView.setTextValue(value: String?) {
value?.let {
setValue(value)
}
}
#InverseBindingAdapter(attribute = "textValue")
fun TextInputView.getTextValue(): String {
return value()
}
#BindingAdapter("textValueAttrChanged")
fun TextInputView.setListener(textAttrChanged: InverseBindingListener) {
val inputValue = findViewById<TextInputEditText>(R.id.input_value)
inputValue.addTextChangedListener(object : TextWatcher {
override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
}
override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
}
override fun afterTextChanged(s: Editable?) {
textAttrChanged.onChange()
}
})
}
I have the following screen which go to the next fragment on button click. Using Navigation component.
But from the next screen, when I'm pressing back button to come back to the search form, the TextInputLayout values for hint, and helperText are all the same.
The only place I set those is inside the custom view. And from debugging I can see that all the correct values are set at that time.
I'm a bit out of ideas about what's going on there. Any hints would be appreciated.
Material library version used: 1.3.0-alpha04
All codebase has been migrated to view binding according the latest changes
The View is used as followed:
<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<data>
<variable
name="viewModel"
type="com.ubigo.features.v2.products.taxi.SearchViewModel" />
<variable
name="dateFormat"
type="com.ubigo.ubicore.date.UbiDate" />
</data>
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/rental_search_root"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/background">
<androidx.cardview.widget.CardView
android:id="#+id/rental_search_form"
style="#style/WhiteCardView"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/textView10">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/constraintLayout3"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.ubigo.ubicore.ui.TextInputView
android:id="#+id/pickup"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
app:hint="#string/product_start"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:startIconDrawable="#drawable/ic_calendar"
app:textValue="#{dateFormat.getPrettyDate(viewModel.pickupDateTime)}" />
<View
android:id="#+id/divider6"
android:layout_width="0dp"
android:layout_height="1dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:background="?android:attr/listDivider"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/pickup" />
<com.ubigo.ubicore.ui.TextInputView
android:id="#+id/dropoff"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
app:hint="#string/product_end"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/divider6"
app:startIconDrawable="#drawable/ic_calendar"
app:textValue="#{dateFormat.getPrettyDate(viewModel.destinationDatetime)}" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
<com.ubigo.ubicore.ui.LoaderButton
android:id="#+id/rental_search_button"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="32dp"
android:layout_marginEnd="16dp"
android:text="#string/product_rental_show_car"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/rental_search_location" />
<androidx.cardview.widget.CardView
android:id="#+id/rental_search_location"
style="#style/WhiteCardView"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginTop="32dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/rental_search_form">
<androidx.constraintlayout.widget.ConstraintLayout
android:id="#+id/constraintLayout4"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.ubigo.ubicore.ui.TextInputView
android:id="#+id/user_location"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="8dp"
app:helperText="#string/product_rental_location"
app:helperTextEnabled="true"
app:hint="#string/product_pickup_location"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:startIconDrawable="#drawable/ic_location_on_black_24dp"
app:textValue="#{viewModel.depAddress}" />
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.cardview.widget.CardView>
<TextView
android:id="#+id/textView10"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginTop="16dp"
android:layout_marginEnd="32dp"
android:text="#string/product_rental_weekend"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
</layout>
And the initialization of the Fragment:
class RentalSearchFragment : Fragment() {
val viewModel: SearchViewModel by viewModel()
private val binding get() = _binding!!
private var _binding: FragmentRentalSearchBinding? = null
override fun onCreateView(
inflater: LayoutInflater, container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
if (_binding == null) {
_binding = FragmentRentalSearchBinding.inflate(inflater, container, false)
binding.lifecycleOwner = viewLifecycleOwner
binding.viewModel = viewModel
binding.dateFormat = UbiDate()
}
return binding.root
}
override fun onDestroyView() {
super.onDestroyView()
_binding = null
}
}

I was able to solve this exact problem by implementing onSaveInstanceState, onRestoreInstanceState, dispatchSaveInstanceState, dispatchRestoreInstanceState, and setValues as described here
http://www.devexchanges.info/2016/03/custom-compound-view-in-android.html
The linked above goes into all the necessary detail about how to implement these functions. There's also undoubtedly countless other sources you can find about how to implement this android paradigm.

LinearLayout Add multiple items

I faced a strange problem : I can't add more than one object dynamically on a LinearLayout , if they were already things , that works, So That can display multiple views
I tried with different views , there is only problems when i try to push one after the other
(there is two buttons in index 0 and 1 to test for multiple objects on the layout)
CODE :
val view = layoutInflater.inflate(R.layout.sensor_item, container, false)
val view2 = layoutInflater.inflate(R.layout.nosensor_item, container, false)
val insertPoint = viewOfLayout.findViewById(R.id.box_Parent) as LinearLayout
insertPoint.addView(view, 2)
//insertPoint.addView(view2, 3) //works
This Works too :
//insertPoint.addView(view, 3)
insertPoint.addView(view2, 2) //works
This doesn't works :
insertPoint.addView(view, 2)
insertPoint.addView(view2, 3) //doesn't works
Full Code (fragments.kt):
package com.corrupted.radheat.TEMPER
import android.os.Bundle
import android.support.v4.app.Fragment
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.*
import kotlinx.android.synthetic.main.sensor_item.view.*
class EditFragment : Fragment() {
lateinit var option : Spinner
lateinit var result : TextView
private lateinit var viewOfLayout: View
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View? {
viewOfLayout = inflater.inflate(R.layout.edit_fragment, container, false)
//create a view to inflate the layout_item (the xml with the textView created before)
val view = layoutInflater.inflate(R.layout.sensor_item, container, false)
val view2 = layoutInflater.inflate(R.layout.nosensor_item, container, false)
val insertPoint = viewOfLayout.findViewById(R.id.box_Parent) as LinearLayout
insertPoint.addView(view, 2)
insertPoint.addView(view2, 3)
option = view.spinner as Spinner
result = view.textView7 as TextView
val options = arrayOf("A","V")
option.adapter = ArrayAdapter<String>(activity,android.R.layout.simple_list_item_1,options)
option.onItemSelectedListener = object : AdapterView.OnItemSelectedListener{
override fun onNothingSelected(parent: AdapterView<*>?) {
result.text = "0"
}
override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long) {
result.text = options[position]
}
}
return viewOfLayout
}
class InfoFragment : Fragment() {
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.info_fragment, container, false)
}
}
class ParamsFragment : Fragment() {
override fun onCreateView(
inflater: LayoutInflater,
container: ViewGroup?,
savedInstanceState: Bundle?
): View {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.parameters_fragment, container, false)
}
}
Code of the fragment :
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true">
<LinearLayout
android:id="#+id/box_Parent"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<Button
android:id="#+id/button3"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button" />
<Button
android:id="#+id/button4"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Button" />
</LinearLayout>
Code of the added view :
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:fillViewport="true"
android:id="#+id/constraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent">
<android.support.constraint.ConstraintLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="12dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="12dp"
android:background="#color/background_Item_light"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<TextView
android:id="#+id/textView9"
android:layout_width="wrap_content"
android:layout_height="24dp"
android:text=".0 C°"
android:textColor="#color/Text_Color_Light"
android:textSize="18sp"
app:layout_constraintBottom_toBottomOf="#+id/textView8"
app:layout_constraintStart_toEndOf="#+id/textView8"
app:layout_constraintTop_toTopOf="#+id/textView8"
app:layout_constraintVertical_bias="0.625" />
<TextView
android:id="#+id/textView7"
android:layout_width="wrap_content"
android:layout_height="24dp"
android:layout_marginStart="4dp"
android:text=".0 C°"
android:textColor="#color/Text_Color_Light"
android:textSize="18sp"
app:layout_constraintBottom_toBottomOf="#+id/textView5"
app:layout_constraintStart_toEndOf="#+id/textView5"
app:layout_constraintTop_toTopOf="#+id/textView5"
app:layout_constraintVertical_bias="0.79" />
<TextView
android:id="#+id/textView8"
android:layout_width="wrap_content"
android:layout_height="56dp"
android:layout_marginStart="10dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
android:text="00"
android:textColor="#color/Text_Color_Light"
android:textSize="36sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toEndOf="#+id/imageButton"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.937" />
<TextView
android:id="#+id/textView4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="4dp"
android:layout_marginTop="4dp"
android:text="#string/ROOMtext"
android:textColor="#color/Text_Color_Light"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Spinner
android:id="#+id/spinner"
android:layout_width="45dp"
android:layout_height="43dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="24dp"
android:layout_marginBottom="8dp"
android:background="#color/UI_ITEM_OVERLAP_LIGHT"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageButton
android:id="#+id/imageButton"
android:layout_width="40dp"
android:layout_height="36dp"
android:layout_marginStart="8dp"
android:layout_marginTop="6dp"
android:layout_marginEnd="8dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.4"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:srcCompat="#drawable/ic_keyboard_arrow_up_black_24dp" />
<ImageButton
android:id="#+id/imageButton3"
android:layout_width="40dp"
android:layout_height="36dp"
android:layout_marginStart="8dp"
android:layout_marginTop="2dp"
android:layout_marginEnd="8dp"
android:layout_marginBottom="6dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.4"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/imageButton"
app:srcCompat="#drawable/ic_keyboard_arrow_down_black_24dp" />
<TextView
android:id="#+id/textView5"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="24dp"
android:layout_marginTop="8dp"
android:layout_marginBottom="8dp"
android:text="00"
android:textColor="#color/Text_Color_Light"
android:textSize="36sp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.652" />
</android.support.constraint.ConstraintLayout>
</android.support.constraint.ConstraintLayout>
MainActivity.kt :
package com.corrupted.radheat.TEMPER
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.support.design.widget.BottomNavigationView
import android.support.v4.app.Fragment
import android.widget.*
class MainActivity : AppCompatActivity() {
private val fragmentManager = supportFragmentManager
private val fragmentTransaction = fragmentManager.beginTransaction()
private val editfragment = EditFragment()
private val infofragment = InfoFragment()
private val parametersfragment = ParamsFragment()
private fun showFragment(fragment: Fragment) {
val fragmentManager = supportFragmentManager
fragmentManager.beginTransaction()
.replace(R.id.fragment_container, fragment)
.commit()
}
private val mOnNavigationItemSelectedListener = BottomNavigationView.OnNavigationItemSelectedListener { item ->
when (item.itemId) {
R.id.action_edit -> {
showFragment(editfragment)
return#OnNavigationItemSelectedListener true
}
R.id.action_info-> {
showFragment(infofragment)
return#OnNavigationItemSelectedListener true
}
R.id.action_Settings-> {
showFragment(parametersfragment)
return#OnNavigationItemSelectedListener true
}
}
false
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
fragmentTransaction.add(R.id.fragment_container, infofragment)
fragmentTransaction.commit()
setContentView(R.layout.activity_main)
val navigation = findViewById<BottomNavigationView>(R.id.activity_main_bottom_navigation)
navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener)
// Create a GLSurfaceView instance and set it
// as the ContentView for this Activity.
}
}
Pic of it working : https://imgur.com/gallery/mLb4G5b
Thanks

BaseAdapter doesn't work in Fragment via PagerView

so I'm trying to make a PagerView via Fragments containing a multiple BaseAdapters in them, but I ran into a little problem with BaseAdapter, I have multiple Fragment, but I'll post 1 as an example
class SpellManagement : Fragment(){
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
listViewSpells?.adapter = AllSpells()
return inflater.inflate(R.layout.activity_spell, container, false)
}
}
class AllSpells: BaseAdapter() {
override fun getCount(): Int {
return player.learnedSpells.size/5+1
}
override fun getItemId(position: Int): Long {
return position.toLong()
}
override fun getItem(position: Int): Any {
return "TEST STRING"
}
override fun getView(position: Int, convertView: View?, viewGroup: ViewGroup?): View {
val rowMain: View
val index:Int = if(position == 0) 0 else{
position*5
}
if (convertView == null) {
val layoutInflater = LayoutInflater.from(viewGroup!!.context)
rowMain = layoutInflater.inflate(R.layout.row_spells_managment, viewGroup, false)
val viewHolder = ViewHolder(rowMain.buttonSpellsManagment1,rowMain.buttonSpellsManagment2,rowMain.buttonSpellsManagment3,rowMain.buttonSpellsManagment4)
rowMain.tag = viewHolder
} else rowMain = convertView
val viewHolder = rowMain.tag as ViewHolder
viewHolder.buttonSpellsManagement1.setBackgroundResource(player.learnedSpells[index]!!.drawable)
viewHolder.buttonSpellsManagement2.setBackgroundResource(player.learnedSpells[index+1]!!.drawable)
viewHolder.buttonSpellsManagement3.setBackgroundResource(player.learnedSpells[index+2]!!.drawable)
viewHolder.buttonSpellsManagement4.setBackgroundResource(player.learnedSpells[index+3]!!.drawable)
viewHolder.buttonSpellsManagement1.setOnClickListener {
}
viewHolder.buttonSpellsManagement2.setOnClickListener {
}
viewHolder.buttonSpellsManagement3.setOnClickListener {
}
viewHolder.buttonSpellsManagement4.setOnClickListener {
}
return rowMain
}
private class ViewHolder(val buttonSpellsManagement1: Button, val buttonSpellsManagement2: Button, val buttonSpellsManagement3: Button, val buttonSpellsManagement4: Button)
}
I was originally using activities, but in the case of PagerView I've changed it to Fragment. What I know is, that I can't call this etc. what I found in java codes was in some cases getActivity() instead of this, which I couldn't find in Kotlin. So by saying that it could be in the viewGroup!!.context in the BaseAdapter.
Any help will be appreciated, thanks.
XML:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:screenOrientation="landscape">
<android.support.constraint.Guideline
android:id="#+id/guideline9"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_percent="0.8" />
<android.support.constraint.Guideline
android:id="#+id/guideline30"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="15dp"
android:orientation="horizontal"
app:layout_constraintEnd_toStartOf="#+id/listViewSpells"
app:layout_constraintGuide_percent="0.4"
app:layout_constraintStart_toStartOf="parent" />
<android.support.constraint.Guideline
android:id="#+id/guideline10"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="87dp"
android:orientation="vertical"
app:layout_constraintEnd_toStartOf="#+id/guideline7"
app:layout_constraintGuide_percent="0.1925"
app:layout_constraintStart_toEndOf="#+id/guideline11" />
<android.support.constraint.Guideline
android:id="#+id/guideline11"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="30dp"
android:layout_marginEnd="83dp"
android:orientation="vertical"
app:layout_constraintEnd_toStartOf="#+id/guideline10"
app:layout_constraintGuide_percent="0.05"
app:layout_constraintStart_toStartOf="parent" />
<android.support.constraint.Guideline
android:id="#+id/guideline13"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="86dp"
android:orientation="vertical"
app:layout_constraintEnd_toStartOf="#+id/guideline14"
app:layout_constraintGuide_percent="0.4825"
app:layout_constraintStart_toEndOf="#+id/guideline7" />
<android.support.constraint.Guideline
android:id="#+id/guideline14"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="7dp"
android:orientation="vertical"
app:layout_constraintEnd_toStartOf="#+id/imageView3"
app:layout_constraintGuide_percent="0.63"
app:layout_constraintStart_toEndOf="#+id/guideline13" />
<android.support.constraint.Guideline
android:id="#+id/guideline15"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.774" />
<android.support.constraint.Guideline
android:id="#+id/guideline16"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_percent="0.92" />
<android.support.constraint.Guideline
android:id="#+id/guideline7"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="83dp"
android:orientation="vertical"
app:layout_constraintEnd_toStartOf="#+id/guideline13"
app:layout_constraintGuide_percent="0.34"
app:layout_constraintStart_toEndOf="#+id/guideline10" />
<ListView
android:id="#+id/listViewSpells"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginStart="16dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="16dp"
android:layout_marginBottom="8dp"
app:layout_constraintBottom_toTopOf="#+id/guideline9"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintEnd_toStartOf="#+id/guideline14"
app:layout_constraintStart_toEndOf="#+id/guideline30"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/textViewInfoSpell"
android:layout_width="0dp"
android:layout_height="141dp"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
app:layout_constraintBottom_toTopOf="#+id/guideline9"
app:layout_constraintDimensionRatio="H,1:1.25"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="#+id/guideline14"
app:layout_constraintTop_toTopOf="#+id/guideline30" />
<ImageView
android:id="#+id/imageView2"
android:layout_width="0dp"
android:layout_height="75dp"
android:layout_marginStart="8dp"
android:layout_marginEnd="8dp"
app:layout_constraintBottom_toTopOf="#+id/guideline30"
app:layout_constraintDimensionRatio="H,1:1"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="#+id/guideline14"
app:layout_constraintTop_toBottomOf="#+id/imageView3" />
<ImageView
android:id="#+id/imageView3"
android:layout_width="0dp"
android:layout_height="47dp"
android:layout_marginStart="8dp"
android:layout_marginEnd="7dp"
app:layout_constraintDimensionRatio="H,"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintStart_toEndOf="#+id/guideline14"
app:layout_constraintStart_toStartOf="#+id/guideline14"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>

I think you need to do your adapter works after declaring a view. In activity, after calling onCreate method we can get a view for our other works. Its slighting different in fragments. We can have view after inflating your view.
First, create a view as a first line of your onCreateView function.
val view = inflater!!.inflate(R.layout.activity_spells, container, false)
Second, return that view from your onCreateView function.
Finally, you can put(use) your other works between those. In that way, you can use the viwe (your fragment) as a variable view. Your SpellManagement class will be looks like this :
class SpellManagement : Fragment(){
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val view = inflater!!.inflate(R.layout.R.layout.activity_spells, container, false)
\**
Your other codes or works here
*\
listViewSpells?.adapter = AllSpells()
return view
}
}
I think this might helps. Cheer!

So... this was REALLY strange to me, the answer was to create a new ListView with the old nowadays not very used "view.FindViewById(...)" thingie, which I've never used before because of the plugins, that allows you to straight up write the name of the component such as "listView.adapter = ..." instead of external defining it by "view.findViewById(...)" thingie. Also with the combination of this answer by MinnKhant.The final code looks as follows:
class SpellManagement : Fragment(){
override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
val view = inflater!!.inflate(R.layout.activity_spell_managment, container, false)
val listView:ListView = view.findViewById(R.id.listViewSpells)
listView.adapter = AllSpells()
return view
}
}
Cheers
Edit: or just write view.listViewSpells.adapter = AllSpells(), instead of findViewById(...)