Develop Reference

Unable to get the data from EditText view in the alert dialog

I created an alertDialog which basically contains two editTexts to enter the data(component Id, component name).When the user clicks on yes button in the alert dialog new component is added to the datbase(as of now I haven't added any on click listeners for yes and no buttons in the dialog) but for some reason I can't get the data from the edit text. I'm new to android app development please help me out guys.....Thanks in Advance :)
Note : 1. I'm using viewModel.flag so that the alertDialog stays persistent with rotations.
onCancel() method simply cancels the alertDialog(I intend to use this for updating certain parameters).
This is kotlin code which creates the alert dialogs.
fun onAddComponent()
{
val builder = AlertDialog.Builder(requireActivity())
builder?.setTitle("New Component Info")
val inflater = requireActivity().layoutInflater
builder?.setView(inflater.inflate(R.layout.new_comp, null))
builder?.setPositiveButton(R.string.Okay_button){ dialogInterface, which->
viewModel.flag = false
val editText : EditText? = compAlert?.findViewById(R.id.new_Component)
println(editText.toString())
}
builder?.setNegativeButton(R.string.NO){ dialogInterface, which->
viewModel.flag = false
}
compAlert= builder?.create()
compAlert?.setOnCancelListener{OnCancel()}
viewModel.flag = true
compAlert?.show()
}
This is the xml layout which I inflated in the onAddComponent()
<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">
<EditText
android:id="#+id/new_Component"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:ems="10"
android:hint="comp Id"
android:inputType="textPersonName"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<EditText
android:id="#+id/new_component_name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:ems="10"
android:hint="comp name"
android:inputType="textPersonName"
app:layout_constraintEnd_toEndOf="#+id/new_Component"
app:layout_constraintStart_toStartOf="#+id/new_Component"
app:layout_constraintTop_toBottomOf="#+id/new_Component" />
</androidx.constraintlayout.widget.ConstraintLayout>

To get the text inside the EditText you need to do editText.getText().toString() and NOT editText.toString() which you have in your code.
In your code, editText.toString() will return the string representation of the editText object. See the documentation of String's toString() method here.

How to use Two-way data binding in android (kotlin)

I need to enable my Button after check some condition, i want to call one method using #InverseBinding OR Two Way data binding and reflect the changes with return value.
my Code :
<Button
android:id="#+id/save_btn_disabled_3"
android:enabled="#={controller}"
....
/>
my Two Way data binding logic here :
#InverseBindingAdapter(attribute = "enable")
fun getEnableButton(view:View, controller:Controller): Boolean {
//some conditions
return false
}
i want to know am i going in correct direction ?, code is ok ?
please suggest me.

First Add Button Status Object
<variable
name="button"
type="com.brl.test.app.vm.ButtonStatus" />
<Button
android:id="#+id/save_btn_disabled_3"
bind:state_change="#{button.state}"
....
/>
Set your logic in buttonEnabled funtion then Enable Your Button
#BindingAdapter({"bind:state_change"})
public static void buttonEnabled(TextView view, State state) {
view.setEnabled(true);
}

You can set one variable in field like:
<variable
name="wantsToVisibleProgress"
type="boolean" />
and set it in your button like this:
<Button
android:id="#+id/constraint_select_main"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/bg_button_blue_big"
android:enabled="#={wantsToVisibleProgress}"
android:gravity="center"
android:onClick="#{v -> fragment.onClick()}"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/txt_evse_one">
You can set that value like this:
binding.setWantsToVisibleProgress(true);

Why is my AutoCompleteTextView not working?

This feels strange as normally the widgets work as they are supposed to. I have an AutoCompleteTextView that I want to populate with a list of city names. It seems simple but doesn't work as I intend to. Here is the resulting output:
Here is the layout in picture:
<?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"
tools:context=".MainActivity1">
<AutoCompleteTextView
android:id="#+id/autocomptv_city_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginStart="20dp"
android:layout_marginLeft="20dp"
android:layout_marginTop="12dp"
android:layout_marginEnd="20dp"
android:layout_marginRight="20dp"
android:background="#drawable/bg_edittext_rect_opd"
android:hint="Select City"
android:text=""
android:inputType="text"
android:maxLines="1"
android:completionThreshold="0"
android:padding="10dp"
android:singleLine="true"
android:textColor="#000000"
android:textSize="15sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</android.support.constraint.ConstraintLayout>
And below is the java code for the same:
public class MainActivity1 extends AppCompatActivity {
AutoCompleteTextView mAutCompleteTextViewSelfCity;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main1);
mAutCompleteTextViewSelfCity = ((AutoCompleteTextView) findViewById(R.id.autocomptv_city_list));
setupCityDropdownwidget();
}
private void setupCityDropdownwidget() {
Type listType = new TypeToken<List<CityName>>() {}.getType();
List<CityName> citiesList = Singletons.getGsonInstance().fromJson(TestData.cityDataJson, listType);
CityArrayAdapter adapter = new CityArrayAdapter(this, R.layout.item_spinner_city, citiesList);
mAutCompleteTextViewSelfCity.setAdapter(adapter);
adapter.notifyDataSetChanged();
mAutCompleteTextViewSelfCity.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
CityName selectedCitySelf = ((CityName) parent.getItemAtPosition(position));
mAutCompleteTextViewSelfCity.setText(selectedCitySelf.getCityName());
}
});
}
}
Problem:
Well, I want the view to be such that as soon as the user taps on it, it shows a dropdown of cities and when the user starts typing their city for filtering, the view keeps showing narrowed down suggestions for the same.
Currently, the only time it is able to suggest is when I type in something and empty out the text view. If I change the completion threshold to 1, no suggestions are shown ever.
What's wrong with my code?
Here is the complete source for reference: https://wetransfer.com/downloads/ce4017f5f2488288ef7494dc029e033420191019092536/7afa9a3e64afb257293533bd634d6c3220191019092536/dc2341

So ultimately, it turned out to be about the basics - The data item that ArrayAdapter works with, should provide a meaningful toString() override. That is what had been missing from my implementation.
From the docs:
By default, the array adapter creates a view by calling
Object#toString() on each data object in the collection you provide,
and places the result in a TextView.
I did end up wasting up some time but the experience and knowledge would surely come in handy some day.

YOu don't need to set adapter.notifyDataSetChanged();, just set your adapter and everything goes fine.

Binding event not firing on Adapter

I am following Android Archt. component to build a project. Following the guidelines I have created a custom Adapter named CataloguesAdapter extending DataBoundListAdapter as :
public class CataloguesAdapter extends DataBoundListAdapter<CatalogueEntity, CatalogueItemBinding> {
private final android.databinding.DataBindingComponent dataBindingComponent;
private final ContributorClickCallback callback;
private CatalogueItemBinding mBinding;
public CataloguesAdapter(DataBindingComponent dataBindingComponent,
ContributorClickCallback callback) {
this.dataBindingComponent = dataBindingComponent;
this.callback = callback;
}
#Override
protected CatalogueItemBinding createBinding(ViewGroup parent) {
mBinding = DataBindingUtil
.inflate(LayoutInflater.from(parent.getContext()),
R.layout.catalogue_item, parent, false,
dataBindingComponent);
//while this click event is working fine
mBinding.getRoot().setOnClickListener(v -> {
CatalogueEntity catalogueEntity = mBinding.getCatalogue();
if (catalogueEntity != null && callback != null) {
callback.onClick(catalogueEntity);
}
});
//todo:not working, this event is not firing
mBinding.deleteIcon.setOnClickListener(v-> callback.onItemDelete());
return mBinding;
}
}
I am implementing swipe to delete layout on Recycler view item. Below is the XML layout of list item:
<?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="catalogue"
type="com.mindtree.igxbridge.traderapp.datasource.local.entity.CatalogueEntity" />
</data>
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardUseCompatPadding="true">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<RelativeLayout
android:id="#+id/view_background"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/colorRed">
<ImageView
android:id="#+id/delete_icon"
android:layout_width="#dimen/dimen_30_dp"
android:layout_height="#dimen/dimen_30_dp"
android:layout_alignParentEnd="true"
android:layout_centerVertical="true"
android:layout_marginEnd="#dimen/dimen_10_dp"
app:srcCompat="#drawable/ic_delete"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:layout_marginEnd="#dimen/dimen_10_dp"
android:layout_toStartOf="#id/delete_icon"
android:text="#string/text_delete"
android:textColor="#color/Material.87.white"
android:textSize="14sp" />
</RelativeLayout>
<RelativeLayout
android:id="#+id/view_foreground"
android:layout_width="match_parent"
android:background="#FFFFFF"
android:layout_height="wrap_content">
<android.support.v7.widget.AppCompatImageView
android:id="#+id/arrow_icon"
android:layout_width="#dimen/dimen_30_dp"
android:layout_height="#dimen/dimen_30_dp"
android:layout_alignParentEnd="true"
android:layout_centerVertical="true"
android:layout_marginEnd="#dimen/dimen_10_dp"
app:srcCompat="#drawable/ic_arrow_right" />
</RelativeLayout>
</FrameLayout>
</android.support.v7.widget.CardView>
</layout>
Another operation like swipe left/right is working fine but clicking on Delete button event is not getting called.
I tried checking findViewbyId and register click event by that, but no luck with that too.
While CatalogueItemBinding is registered correctly, I am not able to find any other source of error.
Thanks.

Correct me if I have misunderstood your code. You used a FrameLayout to host two relative layouts one top of each other (foreground and background). The delete button is in the background and foreground has match_parent in its width attribute. Therefore, I think the delete button is getting covered by the foreground, leading to "not firing of the event".
Possible Solution
Try incorporating the delete button in the foreground. It makes sense to put UI components in the front.

I think you forget to tell your adapter class to where your XML is set or not to adapter class. just create a variable in XML which will import your adapter class have look.
<variable
name="myAdapter"
type="import your adapter class">
</variable>
Now set this variable to your adapter.
#Override
protected CatalogueItemBinding createBinding(ViewGroup parent) {
mBinding = DataBindingUtil
.inflate(LayoutInflater.from(parent.getContext()),
R.layout.catalogue_item, parent, false,
dataBindingComponent);
mBinding .setmyAdapter(this);
return mBinding;
}
}
then your click will work. Hope it will help you.

How to bind method on RadioGroup on checkChanged event with data-binding

I was searching over the internet for how to perform the new cool android data-binding over the RadioGroup and I didn't find a single blog post about it.
Its a simple scenario, based on the radio button selected, I want to attach a callback event using android data binding. I don't find any method on the xml part which allows me to define a callback.
Like here is my RadioGroup:
<RadioGroup
android:id="#+id/split_type_radio"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:checkedButton="#+id/split_type_equal"
android:gravity="center"
<!-- which tag ? -->
android:orientation="horizontal">
...
</RadioGroup>
How do I attach a handler method which will be called on RadioGroup's checkChnged event will fire using data-binding?
I have tried using onClick (don't know if it is the same) in layout file and defining method in the Activity and located it using this in the layout file:
<variable
name="handler"
type="com.example.MainActivity"/>
...
<RadioGroup
android:onClick="handler.onCustomCheckChanged"
.. >
And defined method onCustomCheckChanged like this:
public void onCustomCheckChanged(RadioGroup radio, int id) {
// ...
}
But, it gives me the compilation error:
Error:(58, 36) Listener class android.view.View.OnClickListener with method onClick did not match signature of any method handler.onCustomCheckChanged
I have seen many blogs mentioning it is possible with RadioGroup but non of them really say how. How can I handle this with data-binding ?

After digging to the bunch of methods, I found this question on SO which helped me understand how to bind single methods of listeners.
Here is what to do with RadioGroup:
In RadioGroup listener you have a method onCheckedChanged(RadioGroup g, int id). So you can directly bound that method to your handler or your activity by passing an instance of it as a variable in layout file and calling a method with the same signature.
So call on layout file like this:
<RadioGroup
android:id="#+id/split_type_radio"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:checkedButton="#+id/split_type_equal"
android:gravity="center"
android:onCheckedChanged="#{handler.onSplitTypeChanged}"
android:orientation="horizontal">
...
</RadioGroup>
And in my activity or handler, I need to simply provide the method with same name and signature like this:
public void onSplitTypeChanged(RadioGroup radioGroup,int id) {
// ...
}
Just make sure method is public.
NOTE: This works for any (most of, I have not tried all) listener methods. Like for EditText you can provide android:onTextChanged and so on.

I am using a string, and in this case I have bindable based on viewModel.getCommuteType() viewModel.setCommuteType(String)
<RadioGroup
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
android:checked="#{viewModel.commuteType.equals(Commute.DRIVING)}"
android:onClick="#{()->viewModel.setCommuteType(Commute.DRIVING)}"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="D"/>
<RadioButton
android:checked="#{viewModel.commuteType.equals(Commute.BICYCLE)}"
android:onClick="#{()->viewModel.setCommuteType(Commute.BICYCLE)}"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="B"/>
<RadioButton
android:checked="#{viewModel.commuteType.equals(Commute.WALKING)}"
android:onClick="#{()->viewModel.setCommuteType(Commute.WALKING)}"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="W"/>
<RadioButton
android:checked="#{viewModel.commuteType.equals(Commute.BUS)}"
android:onClick="#{()->viewModel.setCommuteType(Commute.BUS)}"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="T"/>

After some hours I found easy way: two-way databinding in android. It's base skeleton with livedata and Kotlin. Also you can use ObservableField()
Set your viewmodel to data
Create your radiogroup with buttons as you like. Important: set all radio buttons id !!!
Set in your radio group two-way binding to checked variable (use viewmodel variable)
Enjoy)
layout.xml
<data>
<variable
name="VM"
type="...YourViewModel" />
</data>
<LinearLayout
android:id="#+id/settings_block_env"
...
>
<RadioGroup
android:id="#+id/env_radioGroup"
android:checkedButton="#={VM.radio_checked}">
<RadioButton
android:id="#+id/your_id1"/>
<RadioButton
android:id="#+id/your_id2" />
<RadioButton
android:id="#+id/your_id3"/>
<RadioButton
android:id="#+id/your_id4"/>
</RadioGroup>
</LinearLayout>
class YourViewModel(): ViewModel {
var radio_checked = MutableLiveData<Int>()
init{
radio_checked.postValue(R.id.your_id1)//def value
}
//other code
}

Often you care more about what was actually checked instead of "something was checked". In such case alternative solution is to ignore RadioGroup and bind all items as below:
<RadioGroup (...) >
<RadioButton (...)
android:checked="#={viewModel.optionA}"/>
<RadioButton (...)
android:checked="#={viewModel.optionB}"/>
<RadioButton (...)
android:checked="#={viewModel.optionC}"/>
</RadioGroup>
where optionA, optionB and optionC are defined in ViewModel like below:
public final ObservableBoolean optionA = new ObservableBoolean();
public final ObservableBoolean optionB = new ObservableBoolean();
public final ObservableBoolean optionC = new ObservableBoolean();
This is usually enough, however if you want to react immediately on click then you can add callBacks and use them like that:
OnPropertyChangedCallback userChoosedA = new OnPropertyChangedCallback() {
#Override
public void onPropertyChanged(Observable sender, int propertyId) {
(...) // basically propertyId can be ignored in such case
}
};
optionA.addOnPropertyChangedCallback(userChoosedA);
Advantage of such approach is that you don't need to compare and track "id".

In my current project, I did it like this.
I have three currency in the project and I choose one of them via RadioGroup.
It's enum with currencies:
enum class Currency(val value: Byte) {
USD(0),
EUR(1),
RUB(2);
companion object Create {
fun from(sourceValue: Byte): Currency = values().first { it.value == sourceValue }
fun from(sourceValue: String): Currency = values().first { it.toString() == sourceValue }
}
}
A piece of my ViewModel:
class BaseCurrencyViewModel : ViewModelBase<BaseCurrencyModelInterface>() {
/**
* Selected currency
*/
val currency: MutableLiveData<Currency> = MutableLiveData()
/**
*
*/
init {
currency.value = Currency.USD // Init value
}
}
Part of my layout (pay attention to binding in RadioGroup and tags of RadioButton):
<RadioGroup
android:id="#+id/currencySwitchers"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:selectedCurrency = "#{viewModel.currency}"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintHorizontal_bias="0.5"
app:layout_constraintEnd_toEndOf="parent">
<RadioButton
android:id="#+id/usdSwitcher"
android:text="USD"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:tag="USD"
/>
<RadioButton
android:id="#+id/eurSwitcher"
android:text="EUR"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:tag="EUR"
/>
<RadioButton
android:id="#+id/rubSwitcher"
android:text="RUB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:tag="RUB"
/>
</RadioGroup>
And the final part - binding adapter.
#BindingAdapter("selectedCurrency")
fun setSelectedCurrency(view: View, value: MutableLiveData<Currency>?) {
view.getParentActivity()?.let { parentActivity ->
value?.observe(parentActivity, Observer { value ->
view.findViewWithTag<RadioButton>(value.toString())
?.also {
if(!it.isChecked) {
it.isChecked = true
}
}
}
)
(view as RadioGroup).setOnCheckedChangeListener { radioGroup, checkedId ->
val currency = Currency.from(radioGroup.findViewById<RadioButton>(checkedId).tag as String)
if(value != null && value.value != currency) {
value.value = currency
}
}
}
}
In this way, I got two-way binding between RadioGroup and a property in my ViewModel.