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Just mark 1 checkbox of each question and save answer of each position - kotlin

Good morning, community, I have the following case, I have 1 list of questions with their respective YES/NO answers, which are the checkboxes, what is complicating me is how I can apply 1 validation that only allows marking 1 answer (yes or no), in turn save that answer with its respective position and then save it in a DB.
this is my adapter(preusoadapter.kt)
class preusoadapter(
private val context : Context,
private val listpreguntaspreuso: ArrayList<epreguntas>
) : RecyclerView.Adapter<preusoadapter.PreUsoViewHolder>() {
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): PreUsoViewHolder {
val layoutInflater = LayoutInflater.from(context)
return PreUsoViewHolder(layoutInflater.inflate(R.layout.activity_estructura_listapreuso, parent, false)
)
}
override fun onBindViewHolder(holder: PreUsoViewHolder, position: Int) {
val item = listpreguntaspreuso[position]
holder.render(item)
holder.displayChecked(item.answer)
if (position == 2) {
holder.displayAnswers(setOf(Answer.IVSS, Answer.DSS))
} else if (position == 6) {
holder.displayAnswers(setOf(Answer.FRESERV, Answer.FREDMANO))
} else if (position == 14) {
holder.displayAnswers(setOf(Answer.NA, Answer.SI, Answer.NO))
} else if (position == 18) {
holder.displayAnswers(setOf(Answer.NA, Answer.SI, Answer.NO))
} else if (position == 22) {
holder.displayAnswers(setOf(Answer.NA, Answer.SI, Answer.NO))
} else if (position == 25) {
holder.displayAnswers(setOf(Answer.NA, Answer.SI, Answer.NO))
}
}
override fun getItemCount(): Int = listpreguntaspreuso.size
//CLASE INTERNA PREUSOVIEWHOLDER//
inner class PreUsoViewHolder(view: View) : RecyclerView.ViewHolder(view) {
val binding = ActivityEstructuraListapreusoBinding.bind(view)
private val idpregunta = view.findViewById<TextView>(R.id.txtidpregunta)
private val numeropregunta = view.findViewById<TextView>(R.id.txtnumeropregunta)
private val pregunta = view.findViewById<TextView>(R.id.txtpreguntas)
private val imgestado = view.findViewById<ImageView>(R.id.icosemaforo)
fun render (epreguntas: epreguntas){
idpregunta.text = epreguntas.id_pregunta
numeropregunta.text = epreguntas.num_pregunta
pregunta.text = epreguntas.pregunta
Glide.with(imgestado.context).load(epreguntas.icono_estado).into(imgestado)
}
private val checkboxAnswers = mapOf(
binding.chbksi to Answer.SI,
binding.chbkno to Answer.NO,
binding.chbkna to Answer.NA,
binding.chbkIVSS to Answer.IVSS,
binding.chbkDSS to Answer.DSS,
binding.chbkFSERV to Answer.FRESERV,
binding.chbkfmano to Answer.FREDMANO
)
init {
// set the listener on all the checkboxes
checkboxAnswers.keys.forEach { checkbox ->
checkbox.setOnClickListener { handleCheckboxClick(checkbox) }
}
}
// A function that handles all the checkboxes
private fun handleCheckboxClick(checkbox: CheckBox) {
// get the item for the position the VH is displaying
val item = listpreguntaspreuso[adapterPosition]
// update the item's checked state with the Answer associated with this checkbox
// If it's just been -unchecked-, then that means nothing is checked
checkboxAnswers[checkbox]?.let { answer ->
item.answer = if (!checkbox.isChecked) null else answer
// remember to notify the adapter (so it can redisplay and uncheck any other boxes)
notifyItemChanged(adapterPosition)
}
}
fun displayChecked(answer: Answer?) {
// set the checked state for all the boxes, checked if it matches the answer
// and unchecked otherwise.
// Setting every box either way clears any old state from the last displayed item
checkboxAnswers.forEach { (checkbox, answerType) ->
checkbox.isChecked = answerType == answer
}
}
fun displayAnswers(answers: Collection<Answer>) {
// iterate over each checkbox/answer pair, hiding or displaying as appropriate
checkboxAnswers.forEach { (checkbox, answerType) ->
checkbox.visibility = if (answerType in answers) View.VISIBLE else View.GONE
}
}
}
}
and this is my class epreguntas.kt
class epreguntas(
var id_pregunta: String,
var num_pregunta: String,
var pregunta : String,
var icono_estado: String,
var checkvalor: Boolean = false,
var answer: Answer? = null
) {
}
this is my structure i use for my recylcview
<androidx.cardview.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:animateLayoutChanges="true"
app:cardCornerRadius="2dp"
app:cardElevation="4dp"
app:cardUseCompatPadding="true">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:animateLayoutChanges="true"
android:orientation="vertical">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageView
android:id="#+id/icosemaforo"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="#drawable/ic_android" />
</RelativeLayout>
<LinearLayout
android:id="#+id/contenedor_categoria1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="right"
android:orientation="vertical"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
>
<TextView
android:id="#+id/txtnumeropregunta"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="5dp"
android:layout_alignParentTop="true"
android:text="N°"
android:textSize="14sp"
android:textStyle="bold" />
<TextView
android:id="#+id/txtpreguntas"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="10dp"
android:layout_marginTop="5dp"
android:layout_marginEnd="20dp"
android:layout_toStartOf="#+id/contenedorcheck"
android:textSize="14sp"
android:layout_toEndOf="#+id/txtnumeropregunta"
android:textStyle="bold"
android:text="Preguntas" />
<LinearLayout
android:id="#+id/contenedorcheck"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:paddingEnd="20dp"
>
<CheckBox
android:id="#+id/chbksi"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:text="#string/check_si" />
<CheckBox
android:id="#+id/chbkIVSS"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:visibility="gone"
android:text="#string/check_IVSS" />
<CheckBox
android:id="#+id/chbkFSERV"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:visibility="gone"
android:text="#string/check_freserv" />
<CheckBox
android:id="#+id/chbkno"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="10dp"
android:text="#string/check_no" />
<CheckBox
android:id="#+id/chbkfmano"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:layout_marginEnd="10dp"
android:text="#string/check_fredmano" />
<CheckBox
android:id="#+id/chbkDSS"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:layout_marginEnd="10dp"
android:text="#string/check_DSS" />
<CheckBox
android:id="#+id/chbkna"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:layout_marginEnd="10dp"
android:text="#string/check_na" />
</LinearLayout>
</RelativeLayout>
</LinearLayout>
</LinearLayout>
</androidx.cardview.widget.CardView>
It complies with selecting 1 box and unchecking the other, but I realize that when I check the box for question 1 (yes) another question overlaps and my question 1 is hidden, and I see that in some questions the YES/NO/ NA up to IVSS and DSS
example

Like Tenfour04 says, RadioButtons in a RadioGroup would handle the "only one thing can be selected" functionality. (You'd need a different listener to handle its button id has been selected callbacks.)
But since you're already storing the checked state and displaying it, you can handle that yourself - you just need a way to ensure when one checkbox is checked, the others are stored as unchecked.
An easy way to do that is to store an Int which represents the checkbox that's selected. Say 0 for the first, 1 for the second, and a negative number for none. Because each number represents one checked item, by changing the number you're "unchecking" the others.
If you want to store that in your data object (like with checkvaloryes) you can just do:
class epreguntas(
var id_pregunta: String,
...
var checkvaloryes: Boolean = false,
var id_answer: Int
)
Then your checkbox click listeners just have to store the appropriate value, and in onBindHolder you enable the selected checkbox and disable all the others.
This is basically what using a RadioGroup involves too - you get a button ID when the selection changes (-1 for no selection), you store that, and when you display it you fetch that stored ID and set it on the RadioGroup.
The automatic deselection of other buttons (in single-selection mode) is nice and convenient, but setting the current button in onBindViewHolder will trigger the OnCheckedChangedListener and you can get stuck in a loop, so you'd need to avoid that. One way is to only update your stored value (and notify the adapter of the change) if the current selection ID is different to the stored one.
But you can also use checkboxes and click listeners like you already are, you just have to handle their state yourself. Here's a bit of a long explanation of one way to do it, but it's partly about solving other problems you're probably going to run into.
I'm gonna complicate things a bit, because I feel like it will help you out once you understand what's happening - you have a few things to wrangle here. I'm just posting this as one way to approach that store and display problem.
First, I think it would be a good idea to define your options somewhere. Since you have a fixed set of checkboxes, there's a fixed set of answers, right? You could define those with an enum:
enum class Answer {
SI, NO, IVSS, FRESERV, FREDMANO, DSS, NA
}
And you could store that in your data:
class epreguntas(
...
var answer: Answer? = null // using null for 'no answer selected'
)
(You can use that enum elsewhere in your app too - it means your answer data is in a useful data structure, and it's not tied to some detail about your list display, like what order the checkboxes happen to be added in the layout. If you need to turn these enum constants into an Int, e.g. for storage, you can use their ordinal property)
Now you can connect those responses to the checkboxes that represent them. We could do that in the ViewHolder class:
class PreUsoViewHolder(view: View) : RecyclerView.ViewHolder(view) {
...
// create an answer type lookup for each checkbox in the ViewHolder instance
// I'm going to use your binding object since you have it!
val checkboxAnswers = mapOf(
binding.chbksi to SI,
binding.chbkno to NO,
...
)
That checkboxAnswers map acts as two things - it's a lookup that links each CheckBox in the layout to a specific answer type, and the keys act as a collection of all your CheckBox views, so you can easily do things to all of them together.
Now you can create a click listener that checks which View was clicked, get the matching Answer, and set it:
// I've made this an -inner- class, and it need to be nested inside your Adapter class
// This gives the ViewHolder access to stuff inside the adapter, i.e. listpreguntaspreuso
inner class PreUsoViewHolder(view: View) : RecyclerView.ViewHolder(view) {
init {
...
// set the listener on all the checkboxes
checkboxAnswers.keys.forEach { checkbox ->
checkbox.setOnClickListener { handleCheckboxClick(checkbox) }
}
// A function that handles all the checkboxes
private fun handleCheckboxClick(checkbox: CheckBox) {
// get the item for the position the VH is displaying
val item = listpreguntaspreuso[adapterPosition]
// update the item's checked state with the Answer associated with this checkbox
// If it's just been -unchecked-, then that means nothing is checked
checkboxAnswers[checkbox]?.let { answer ->
item.answer = if (!checkbox.isChecked) null else answer
// remember to notify the adapter (so it can redisplay and uncheck any other boxes)
notifyItemChanged(adapterPosition)
}
}
This relies on you using a click listener, not a checkedChanged listener, because setting checked state in onBindViewHolder (when you're clearing checkboxes) will trigger that checkedChanged listener. A click listener only fires when the user is the one checking or unchecking a box.
So now you have a click listener that sets the appropriate Answer value for an item. To display it, we could put another function in the ViewHolder:
fun displayChecked(answer: Answer?) {
// set the checked state for all the boxes, checked if it matches the answer
// and unchecked otherwise.
// Setting every box either way clears any old state from the last displayed item
checkboxAnswers.forEach { (checkbox, answerType) ->
checkbox.isChecked = answerType == answer
}
}
And now you can call that from onBindViewHolder:
override fun onBindViewHolder(holder: PreUsoViewHolder, position: Int) {
val item = listpreguntaspreuso[position]
holder.render(item)
holder.displayChecked(item.answer)
The other reason for doing things this way, is I think your code to make stuff visible/invisible is broken:
else if (position == 14){
holder.itemView.chbkna.visibility = View.VISIBLE
}
This kind of thing won't work - all you're doing is saying "for item 14, make this box visible" - it says nothing about which of the other boxes should be visible, and which should be hidden. You'll have stuff randomly shown or hidden depending on which item happened to be displayed in that ViewHolder before. You need to explicitly say what should be displayed, every time onBindViewHolder runs.
You can do that with a similar function to the displayChecked one we just wrote:
inner class PreUsoViewHolder(view: View) : RecyclerView.ViewHolder(view) {
...
// provide a list of the answers that should be shown
fun displayAnswers(answers: Collection<Answer>) {
// iterate over each checkbox/answer pair, hiding or displaying as appropriate
checkboxAnswers.forEach { (checkbox, answerType) ->
checkbox.visibility = if (answerType in answers) VISIBLE else GONE
}
}
Now you can easily update your displayed boxes in onBindViewHolder:
else if (position == 14){
holder.displayAnswers(setOf(NA, SI, NO))
}
And even better, you could create groups of answer types associated with the question in the data. So instead of hardcoding by position, you can just pull the required types out of the item itself
class epreguntas(
...
answerTypes: Set<Answer>
// onBindViewHolder
holder.displayAnswers(item.answerTypes)
You could even create preset lists for different types of question, like val yesNo = setOf(SI, NO) (or an enum) and reuse those when defining your questions - there are probably only a few combos you're using anyway!
I hope that wasn't too complicated, and the organisation ideas (and the benefits they can give you) make sense. A RadioGroup is simpler, but with the other stuff you'll probably have to deal with, I feel like this is a useful general approach

How to set click listener to this Button

I cant get this to work I want the sign out Button on this preferences screen to have a ClickListener
This is how it looks like:
Here´s the code and the buttonView is always NULL:
class PreferencesFragment : PreferenceFragmentCompat() {
lateinit var activity: Context
private var prefs: SharedPreferences = BleApplication.getInstance().getDefaultSharedPreferences()
override fun onAttach(context: Context?) {
super.onAttach(context)
activity = requireActivity()
}
override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
super.onViewCreated(view, savedInstanceState)
val buttonView = view.findViewById<View>(R.id.btn_sign_out)
if (buttonView != null) {
buttonView.setOnClickListener {
Toast.makeText(getActivity(), "You clicked me.", Toast.LENGTH_SHORT).show()
}
}
// Hide the divider
/* setDivider(ColorDrawable(Color.TRANSPARENT))
setDividerHeight(0)*/
}
override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
addPreferencesFromResource(R.xml.app_prefs)
}
}
I also tried the kotlinx.android.synthetic but same problem there
Here´s the xml
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory
android:layout="#layout/pref_category_text"
android:title="#string/pref_category_remote_battery_title">
<SwitchPreferenceCompat
android:key="#string/pref_key_category_remote_battery_switch"
android:title="#string/pref_category_remote_battery_switch_title"
android:summary="#string/pref_category_remote_battery_switch_summ"/>
</PreferenceCategory>
<PreferenceCategory
android:layout="#layout/pref_category_text"
android:title="#string/pref_category_sign_out_title">
<Preference
android:key="#string/pref_key_category_signed_out"
android:widgetLayout="#layout/pref_category_sign_out_button"
android:title="#string/pref_category_sign_out_button_title"
android:summary="#string/pref_category_sign_out_buttom_summ"/>
</PreferenceCategory>
</PreferenceScreen>
Here is the "#layout/pref_category_sign_out_button" layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<Button
android:id="#+id/btn_sign_out"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/buttonshape"
android:text="#string/pref_category_sign_out_title" />
</LinearLayout>

Since your Fragment extends from PreferenceFragmentCompat, you should not try to set a View.OnClickListener but override PreferenceFragmentCompat.onPreferenceTreeClick() instead. According to the documentation, this method is ...
Called when a preference in the tree rooted at this PreferenceScreen has been clicked.
Code example in Java:
#Override
onPreferenceTreeClick(Preference preference){
if(preference.getKey().equals(getContext().getString(R.string.pref_key_category_signed_out))){
// user clicked signout "button"
// take appropriate actions
// return "true" to indicate you handled the click
return true;
}
return false;
}
Code example in Kotlin (I hope I can trust Android Studio :P)
override fun onPreferenceTreeClick(preferenceScreen: PreferenceScreen, preference: Preference): Boolean {
return if (preference.key == context.getString(R.string.pref_key_category_signed_out)) {
// user clicked signout "button"
// take appropriate actions
// return "true" to indicate you handled the click
true
} else false
}
This will enable you to catch click events for the Preference but not for the Button.
In order to do that as well, one can use a custom Preference and override onBindViewHolder(PreferenceViewHolder). Since PreferenceViewHolder - similar to RecyclerView.ViewHolder - has a field itemView which contains the inflated layout, here is a good opportunity to set our own View.OnClickListener.
SignOutPreference extends from TwoStatePreference (in the com.android.support:preference-v7 library) because replacing the CheckBox widget with your custom Button requires only to set the android:widgetLayout attribute, just like you do in your code snippet:
<PreferenceCategory
android:layout="#layout/pref_category_text"
android:title="#string/pref_category_sign_out_title">
<your.package.name.SignOutPreference
android:key="#string/pref_key_category_signed_out"
android:widgetLayout="#layout/pref_category_sign_out_button"
android:title="#string/pref_category_sign_out_button_title"
android:summary="#string/pref_category_sign_out_buttom_summ"/>
</PreferenceCategory>
SignOutPreference.java
public class SignOutPreference extends TwoStatePreference {
public SignOutPreference(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
public SignOutPreference(Context context, AttributeSet attrs) {
super(context, attrs);
}
public SignOutPreference(Context context) {
super(context);
}
#Override
public void onBindViewHolder(final PreferenceViewHolder holder) {
super.onBindViewHolder(holder);
Button button = holder.itemView.findViewById(R.id.btn_sign_out);
if(button != null){
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(holder.itemView.getContext(), "CLICKED!", Toast.LENGTH_SHORT).show();
}
});
}
}
}

As #0X0nosugar mentioned you can use the onPreferenceTreeClicked method to handle all clicks in a convenient way like this:
#Override
onPreferenceTreeClick(Preference preference){
if ((preference.getKey().equals(getContext().getString(R.string.pref_key_category_signed_out))){
// user clicked signout "button"
// take appropriate actions
// return "true" to indicate you handled the click
return true;
}
return false;
}
The problem when using a custom button via widgetLayout is that when the button click is not a Preference click, so the handler doesn't catch it. One way to circumvent this problem is to just disable the built-in click for the button, like this:
<Button
android:id="#+id/btn_sign_out"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/buttonshape"
android:text="#string/pref_category_sign_out_title"
android:clickable="false"/>
See the last line. This way you don't need to create an extra class just for the button and you can easily access whatever methods and variables you have in your PreferencesFragment class.
I'm sure there's a better way to somehow trigger the Preference click from the button click, but at least this works as pretty well.

I was looking for a simple answer and found a way. Just set the onClick attribute for the button in the xml file, and implement the method in the parent activity of the preference fragment. (It's important to implement it in the Activity, not in the Preference Fragment. Or else it will give you crashes)
I wanted to make my onClick method to work only when the button is touched(clicked), and not respond to clicks in the area outside of the button. So far this is the only way that works just like I wanted it to.
My code is in Kotlin, but the logic is simple so it won't be hard to write it in java.
This is my button.xml used for the preference's widgetLayout. Look at how I set the android:onClick= attribute.
<?xml version="1.0" encoding="utf-8"?>
<Button
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/btn"
android:text="reset"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
style="#style/rippleEffect" //my custom ripple effect
android:onClick="onClickMethod">
</Button>
Then I implemented the onClickMethod in the parent activity of the preference fragment. This callback method should be public, and have View as input parameter.
(For more info read this -> How exactly does the android:onClick XML attribute differ from setOnClickListener? )
fun onClickMethod(view: View) {
//do something
}
Below is my preference.xml.
<Preference
android:key="pref_key"
android:title="Reset"
android:summary="summary.."
app:iconSpaceReserved="false"
android:widgetLayout="#layout/button"/>
Also I tried to set the ClickListener programmatically, but the only way that worked without errors was when I set the button's ClickListener inside the PreferenceClickListener. This only worked half way, since I need to touch(click) the preference item first to init the button's ClickListener.
val view = findPreference<androidx.preference.Preference>("pref_key")
var isFirst = true
view?.setOnPreferenceClickListener {
if (isFirst) {
btn.setOnClickListener {
Toast.makeText(requireContext(), "button clicked!", Toast.LENGTH_SHORT).show()
}
isFirst = false
it.summary = "unlocked"
} else {
isFirst = true
it.summary = "locked - tap to unlock"
}
true
}
Anyway this answer is working well for me, but I'm still looking for a way to use my preference key since this method does not fully uses the preference attribute, but just as a layout. But for now I hope this is helpful for those who want to use buttons in android preference.

Use group in ConstraintLayout to listen for click events on multiple views

Basically I'd like to attach a single OnClickListener to multiple views inside a ConstraintLayout.
Before migrating to the ConstraintLayout the views where inside one layout onto which I could add a listener. Now they are on the same layer with other views right under the ConstraintLayout.
I tried adding the views to a android.support.constraint.Group and added a OnClickListener to it programmatically.
group.setOnClickListener {
Log.d("OnClick", "groupClickListener triggered")
}
However this does not seem to work as of the ConstraintLayout version 1.1.0-beta2
Have I done something wrong, is there a way to achieve this behaviour or do I need to attach the listener to each of the single views?

The Group in ConstraintLayout is just a loose association of views AFAIK. It is not a ViewGroup, so you will not be able to use a single click listener like you did when the views were in a ViewGroup.
As an alternative, you can get a list of ids that are members of your Group in your code and explicitly set the click listener. (I have not found official documentation on this feature, but I believe that it is just lagging the code release.) See documentation on getReferencedIds here.
Java:
Group group = findViewById(R.id.group);
int refIds[] = group.getReferencedIds();
for (int id : refIds) {
findViewById(id).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// your code here.
}
});
}
In Kotlin you can build an extension function for that.
Kotlin:
fun Group.setAllOnClickListener(listener: View.OnClickListener?) {
referencedIds.forEach { id ->
rootView.findViewById<View>(id).setOnClickListener(listener)
}
}
Then call the function on the group:
group.setAllOnClickListener(View.OnClickListener {
// code to perform on click event
})
Update
The referenced ids are not immediately available in 2.0.0-beta2 although they are in 2.0.0-beta1 and before. "Post" the code above to grab the reference ids after layout. Something like this will work.
class MainActivity : AppCompatActivity() {
fun Group.setAllOnClickListener(listener: View.OnClickListener?) {
referencedIds.forEach { id ->
rootView.findViewById<View>(id).setOnClickListener(listener)
}
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
// Referenced ids are not available here but become available post-layout.
layout.post {
group.setAllOnClickListener(object : View.OnClickListener {
override fun onClick(v: View) {
val text = (v as Button).text
Toast.makeText(this#MainActivity, text, Toast.LENGTH_SHORT).show()
}
})
}
}
}
This should work for releases prior to 2.0.0-beta2, so you can just do this and not have to do any version checks.

The better way to listen to click events from multiple views is to add a transparent view as a container on top of all required views. This view has to be at the end (i.e on top) of all the views you need to perform a click on.
Sample container view :
<View
android:id="#+id/view_container"
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="#+id/view_bottom"
app:layout_constraintEnd_toEndOf="#+id/end_view_guideline"
app:layout_constraintStart_toStartOf="#+id/start_view_guideline"
app:layout_constraintTop_toTopOf="parent"/>
Above sample contains all four constraint boundaries within that, we can add views that to listen together and as it is a view, we can do whatever we want, such as ripple effect.

To complement the accepted answer for Kotlin users create an extension function and accept a lambda to feel more like the API group.addOnClickListener { }.
Create the extension function:
fun Group.addOnClickListener(listener: (view: View) -> Unit) {
referencedIds.forEach { id ->
rootView.findViewById<View>(id).setOnClickListener(listener)
}
}
usage:
group.addOnClickListener { v ->
Log.d("GroupExt", v)
}

The extension method is great but you can make it even better by changing it to
fun Group.setAllOnClickListener(listener: (View) -> Unit) {
referencedIds.forEach { id ->
rootView.findViewById<View>(id).setOnClickListener(listener)
}
}
So the calling would be like this
group.setAllOnClickListener {
// code to perform on click event
}
Now the need for explicitly defining View.OnClickListener is now gone.
You can also define your own interface for GroupOnClickLitener like this
interface GroupOnClickListener {
fun onClick(group: Group)
}
and then define an extension method like this
fun Group.setAllOnClickListener(listener: GroupOnClickListener) {
referencedIds.forEach { id ->
rootView.findViewById<View>(id).setOnClickListener { listener.onClick(this)}
}
}
and use it like this
groupOne.setAllOnClickListener(this)
groupTwo.setAllOnClickListener(this)
groupThree.setAllOnClickListener(this)
override fun onClick(group: Group) {
when(group.id){
R.id.group1 -> //code for group1
R.id.group2 -> //code for group2
R.id.group3 -> //code for group3
else -> throw IllegalArgumentException("wrong group id")
}
}
The second approach has a better performance if the number of views is large since you only use one object as a listener for all the views!

While I like the general approach in Vitthalk's answer I think it has one major drawback and two minor ones.
It does not account for dynamic position changes of the single views
It may register clicks for views that are not part of the group
It is not a generic solution to this rather common problem
While I'm not sure about a solution to the second point, there clearly are quite easy ones to the first and third.
1. Accounting position changes of element in the group
This is actually rather simple. One can use the toolset of the constraint layout to adjust the edges of the transparent view.
We simply use Barriers to receive the leftmost, rightmost etc. positions of any View in the group.
Then we can adjust the transparent view to the barriers instead of concrete views.
3. Generic solution
Using Kotlin we can extend the Group-Class to include a method that adds a ClickListener onto a View as described above.
This method simply adds the Barriers to the layout paying attention to every child of the group, the transparent view that is aligned to the barriers and registers the ClickListener to the latter one.
This way we simply need to call the method on the Group and do not need to add the views to the layout manually everytime we need this behaviour.

in Constraintlayout 2.0.0,you can use Layer to resolve multiple views click event,and also support scale animation

For the Java people out there like me:
public class MyConstraintLayoutGroup extends Group {
public MyConstraintLayoutGroup(Context context) {
super(context);
}
public MyConstraintLayoutGroup(Context context, AttributeSet attrs) {
super(context, attrs);
}
public MyConstraintLayoutGroup(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
public void setOnClickListener(OnClickListener listener) {
for (int id : getReferencedIds()) {
getRootView().findViewById(id).setOnClickListener(listener);
}
}
}
This is not propagating click states to all other children however.

fun ConstraintLayout.setAllOnClickListener(listener: (View) -> Unit) {
children.forEach { view ->
rootView.findViewById<View>(view.id).setOnClickListener { listener.invoke(this) }
}
}
And then
.setAllOnClickListener {
do something
}

How to disable all buttons in a Layout?

The way app works is the following: App prompts 30 buttons to user and user may guess the right ones by tapping. When user taps some button all the buttons (say a view containing these buttons) should be locked while corresponding (right or wrong guess) animation is playing. Tapped button by itself should be disabled till the next round. After animation is finished all not tapped previously buttons (say a view containing these buttons) should be available again.
So I have a Layout which includes another layout with these 30 buttons:
...
<RelativeLayout
android:id="#+id/alphabetContainer"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<include layout="#layout/alphabet" />
</RelativeLayout>
...
Now I need to lock the buttons from being clicked and then unlock. So I tried:
...
private RelativeLayout alphabetPanel;
...
public void onCreate(){
...
alphabetPanel = (RelativeLayout) findViewById(R.id.alphabetContainer);
...
}
...
private void lockButtons(){
alphabetPanel.setEnabled(false);
}
but this doesn't lock buttons. I also tried:
alphabetPanel.setFocusable(false);
alphabetPanel.setClickable(false);
Doesn't help either. Seems like it all relies only to a layout by itself but not the views it contains.
Also I tried to add a fake layout to place it over layout with buttons by bringing it to the front. This is a workaround and its tricky cuz both layouts must be placed inside a RelativeLayout only:
...
blockingLayout = new RelativeLayout(this);
blockingLayout.setLayoutParams(alphabetPanel.getLayoutParams());
...
but this works very strange: somehow both layouts in this case appears and disappears every second or so or doesn't appear at all - I cant understand that at all cuz there is no setVisibility() method used in code!
The only one way left is to iterate every view (button) to make it disabled and than back.
Is there any other way?
UPDATE
Finally I had to add a "wall"-layout into the xml. Now by making it clickable and focusable it becomes a solution.

Try setting for each Button's xml definition
android:duplicateParentState="true"
I'm not sure, but I think it should make them not only to seem disabled, but also to act accordingly.

Hmm it surprises me that disabling the parent-layout doesn't work.. as far as i know it should.
Try fetching your included layout instead, and disable that.
Anyway, if all else fails you can always loop through the buttons themselves.
for(int i=0;i<relativeLayout.getChildCount();i++){
View child=relativeLayout.getChildAt(i);
//your processing....
child.setEnabled(false);
}

I used extension to lock and unlock the view
//lock
fun View.lock() {
isEnabled = false
isClickable = false}
//unlock
fun View.unlock() {
isEnabled = true
isClickable = true}
if you want to lock all children of the view group
//lock children of the view group
fun ViewGroup.lockAllChildren() {
views().forEach { it.lock() }}
//unlock children of the view group
fun ViewGroup.unlockAllChildren() {
views().forEach { it.unlock() }}

firstly define your button
Button bit = (Button)findViewById(R.id.but);
bit.setEnabled(false);
and set enabled false;

Java:-
public void disableButtons(Layout layout) {
// Get all touchable views
ArrayList<View> layoutButtons = layout.getTouchables();
// loop through them, if they are instances of Button, disable them.
for(View v : layoutButtons){
if( v instanceof Button ) {
((Button)v).setEnabled(false);
}
}
}
Kotlin:-
fun disableButtons(layout: Layout) {
// Get all touchable views
val layoutButtons: ArrayList<View> = layout.getTouchables()
// loop through them, if they are instances of Button, disable them.
for (v in layoutButtons) {
if (v is Button) {
(v as Button).setEnabled(false)
}
}
}
Retrieve all touchables views into an ArrayList, then loop through them and check if it is an instance of the Button or TextView or which ever you want, then disable it!

In case data binding is needed
import android.view.ViewGroup
import android.widget.Button
import androidx.core.view.children
import androidx.databinding.BindingAdapter
#BindingAdapter("disableButtons")
fun ViewGroup.setDisableButtons(disableButtons: Boolean) {
children.forEach {
(it as? Button)?.isEnabled = !disableButtons
}
}
Usage:
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:padding="#dimen/guideline"
app:disableButtons="#{vm.busy}">
....
</androidx.constraintlayout.widget.ConstraintLayout>

Might work in constraint layout . Use group widget and add all the button ids.
In the java code set enabled false for the group.

For disable all buttons in any nested layouts.
void DisableAllButtons( ViewGroup viewGroup ){
for( int i = 0; i < viewGroup.getChildCount(); i++ ){
if( viewGroup.getChildAt(i) instanceof ViewGroup ){
DisableAllButtons( (ViewGroup) viewGroup.getChildAt(i) );
}else if( viewGroup.getChildAt(i) instanceof Button ){
viewGroup.getChildAt(i).setEnabled( false );
}
}
}

write these two lines on your button declartion in XML
android:setEnabled="false"
android:clickable="false"

how to fire an event when someone clicks anywhere on the screen in an android app?

how can I catch the event when click occurs somewhere on the app screen?
It doesn't matter if there is a button or something else. I just need to apply an onClick() event listener on the whole application screen.
How to do this?

setonclicklistner for main layout of your layout file....
Like....main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/mainlayout">
<!- Your other view->
</Relativelayout>
and set click listener for mainlayout...
RelativeLayout rlayout = (RelativeLayout) findViewById(R.id.mainlayout);
rlayout.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});

You should just override Activity's dispatchTouchEvent(ev: MotionEvent) method
Look at this example in Kotlin. This approach will not affect any onClickListenters in your app
/**
* On each touch event:
* Check is [snackbar] present and displayed
* and dismiss it if user touched anywhere outside it's bounds
*/
override fun dispatchTouchEvent(ev: MotionEvent): Boolean {
// dismiss shown snackbar if user tapped anywhere outside snackbar
snackbar?.takeIf { it.isShown }?.run {
val touchPoint = Point(Math.round(ev.rawX), Math.round(ev.rawY))
if (!isPointInsideViewBounds(view, touchPoint)) {
dismiss()
snackbar = null // set snackbar to null to prevent this block being executed twice
}
}
// call super
return super.dispatchTouchEvent(ev)
}
Or check out the full gist

I believe the easiest way is to override onUserInteraction in your Activity
Just be aware that it won't fire when users focus on/off EditTexts and Spinners (probably other Widgets too). But it will fire every time the user touches the screen or presses a Button.
But this makes it unnecessary to build listeners into your layouts or write additional methods to handle those listeners, so I believe it's the most trouble-free way to get what you want.

If you want to know, that the user clicked anywhere on the screen
then the trick is to override OnUserUnteraction():
"Called whenever a key, touch, or trackball event is dispatched to the activity.Implement this method if you wish to know that the user has interacted with the device in some way while your activity is running. This callback and {#link #onUserLeaveHint} are intended to help activities manage status bar notifications intelligently; specifically, for helping activities determine the proper time to cancel a notification...."
public abstract class BaseActivity extends Activity {
...
#Override
public void onUserInteraction() {
Log.d(DEBUG_TAG,"Touch anywhere happened");
super.onUserInteraction();
}
I am using it to set up app screen block after some inactivity.

Give your main layout an id, then
LinearLayout root = (LinearLayout) findViewById(R.id.main_layout);
root.setOnClickListener(new OnClickListener() {
public void onClick()
{
}
});

You can also directly set a callback from the onClick xml attribute of the root layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:onClick"myMethod">
<!- Your other view->
</Relativelayout>
And in your activity:
public void myMethod(View pView) {
//XXX do something
}
Less bloated code this way :)

Maybe you can add a listener to the Layout instance, getting the layout with
RelativeLayout l = (RelativeLayout)findViewById(R.id.mylayout);
l.setOnClickListener(click);