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
I put an EditText with inputType="textPassword" in my activity's XML
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="Enter Password"
android:inputType="textPassword"
android:padding="16dp"
android:id="#+id/passwordInput"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
Till now there is not any problem and I see circles intead of real password characters:
The interesting part is here. Now if I call setSingleLine() on the EditText in the Activity:
class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
passwordInput.setSingleLine()
}
}
will see that the password characters is surprisingly visible!
Another interesting thing is that this issue will not happen if I put android:singleLine="true" in XML of the EditText.
Note: I know that setting setSingleLine on a password field is useless, but I'm curious why calling this function has such side effect.
I think it is because when you call setSingleLine, textview will change it transformation method from PasswordTransformationMethod to SingleLineTransformationMethod. there is only one transformation method accepted at the time in EditText (which is child of TextView)
you can check the source code here:
setSingleLine()
https://android.googlesource.com/platform/frameworks/base/+/jb-mr0-release/core/java/android/widget/TextView.java#6727
follow through the code fill call function setTransformationMethod
https://android.googlesource.com/platform/frameworks/base/+/jb-mr0-release/core/java/android/widget/TextView.java#1461
Try to set it inside XML:
android:inputType="textPassword"
android:maxLines="1"
android:singleLine="true"
I can't tell you why setting it programaticaly lead to this strange behavior because I usually do this inside XML and I'm doing this in code just to manipulate Views.
If you want to hide the password, you will:
yourTextView.setTransformationMethod(new PasswordTransformationMethod());
If you want to show the password, you will:
yourTextView.setTransformationMethod(new DoNothingTransformation()), or setTransformationMethod(null)
Method setTransformationMethod is show/hide text
Now, you can check the code of class TextView, Because of EditText extended from TextView.
You will see in the function setSingleLine(), It's call function applySingleLine(singleLine, true, true), This function will set again setTransformationMethod(SingleLineTransformationMethod.getInstance());
This is change your Transformation(show/hide text of EditText):
private void applySingleLine(boolean singleLine, boolean applyTransformation,
boolean changeMaxLines) {
mSingleLine = singleLine;
if (singleLine) {
setLines(1);
setHorizontallyScrolling(true);
// change Transformation
if (applyTransformation) {
setTransformationMethod(SingleLineTransformationMethod.getInstance());
}
} else {
if (changeMaxLines) {
setMaxLines(Integer.MAX_VALUE);
}
setHorizontallyScrolling(false);
if (applyTransformation) {
setTransformationMethod(null);
}
}
}
I have chosen the TextInputEditText for my password field, for using the toggle password feature.
Here is my xml code:
<com.google.android.material.textfield.TextInputLayout
android:layout_width="#dimen/login_width"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginTop="#dimen/password_margin_top"
app:hintEnabled="false"
app:passwordToggleDrawable="#drawable/password_toggle_drawable"
app:passwordToggleEnabled="true">
<com.google.android.material.textfield.TextInputEditText
android:id="#+id/my_login_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:fontFamily="sans-serif"
android:hint="#string/password"
android:inputType="textPassword"
android:nextFocusDown="#+id/my_login_login"
android:padding="#dimen/field_padding" />
</com.google.android.material.textfield.TextInputLayout>
I have to do some other layout changes on the toggling password. Is there any callback available for this in TextInputLayout?
You can call setEndIconOnClickListener on your TextInputLayout:
textInputLayout.setEndIconOnClickListener { v ->
// Layout changes here
}
However, this removes the click listener responsible for toggling the password transformation method. I would suggest just copying the click listener code in PasswordToggleEndIconDelegate and adding your own functionality on top:
textInputLayout.setEndIconOnClickListener {
val editText: EditText? = textInputLayout.editText
// Store the current cursor position
val selection = editText?.selectionEnd ?: 0
// Check for existing password transformation
val hasPasswordTransformation = editText?.transformationMethod is PasswordTransformationMethod;
if (hasPasswordTransformation) {
editText?.transformationMethod = null
} else {
editText?.transformationMethod = PasswordTransformationMethod.getInstance()
}
// Restore the cursor position
editText?.setSelection(selection)
// Add additional functionality here
}
Edit: This method is only available in material library version 1.1.0-alpha04 onwards and, as of writing, 1.1.0 is still in beta.
First of all, if anything can be better in my question, please let me know, it's my first one here.
I am building an app for android.
I want my users to be able to enter a time in an edittext field quickly. There usually already is a time in there, which should be selected so any input from keyboard will result in it being overwritten, while just hitting "next" (or enter on keyboard" will leave it the way it is and jump to the next field.
For all my fields this works nicely, but for some reason I cannot grasp, the text in this specific field (and its twin) won't get selected no matter what I tried.
I putandroid:selectAllOnFocus="true" in the res file, and when that didn't work I also put v.selectAll() in its onFocusChangedListener.
flighttOutStringField?.onFocusChangeListener = View.OnFocusChangeListener { v, hasFocus ->
if (hasFocus) {
with(v as TextInputEditText) {
previousText = this.text.toString()
v.selectAll()
}
} else {
with(v as TextInputEditText) {
val currentText = this.text.toString()
if (!(("([01]\\d|2[0-3]):[0-5]\\d".toRegex().containsMatchIn(currentText) && currentText.length == 5)
|| ("([01]\\d|2[0-3])[0-5]\\d".toRegex().containsMatchIn(
currentText.padStart(
4,
'0'
)
) && currentText.length <= 4))
|| (currentText == "")
)
this.setText(previousText) // not a valid new entry, so no update on flight
else {
this.setText(
if (currentText.length < 5) "${currentText.padStart(
4,
'0')
.slice(0..1)}:${currentText.padStart(4, '0').slice(2..3)}" else currentText)
flight = flight.copy (tOutString = "${date?.format(DateTimeFormatter.ISO_DATE)}T${this.text}:00", changed = 1)
}
}
}
updating the "flight" var will refill all fields through its setter.
<android.support.design.widget.TextInputLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:id="#+id/flighttOutStringWrapper"
app:layout_constraintStart_toEndOf="#+id/flighttOutSelector" android:layout_marginTop="4dp"
app:layout_constraintTop_toBottomOf="#+id/flightOrigWrapper"
app:layout_constraintHorizontal_bias="0.5"
app:layout_constraintEnd_toStartOf="#+id/flighttInStringWrapper">
<android.support.design.widget.TextInputEditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="time"
android:ems="10"
android:id="#+id/flighttOutStringField"
android:textAlignment="center"
android:includeFontPadding="false"
android:hint="#string/timeOut"
android:nextFocusForward="#id/flighttInStringField" android:imeOptions="actionNext"
android:selectAllOnFocus="true"/>
</android.support.design.widget.TextInputLayout>
I would think that upon selecting the TextInputEditText, all text would be selected, but it isn't.
Then, I thought the v.selectAll() would do that for me, but it also doesn't.
Try this
v.setOnFocusChangeListener(null)
v.clearFocus();
v.requestFocus();
v.selectAll()
v.setOnFocusChangeListener(listener)
I have a RadioGroup like so:
<RadioGroup android:layout_width="wrap_content" android:layout_height="wrap_content"
app:layout_constraintTop_toBottomOf="#+id/player_age"
android:id="#+id/gender"
android:layout_marginStart="8dp" app:layout_constraintStart_toStartOf="parent"
android:layout_marginEnd="8dp" app:layout_constraintEnd_toEndOf="parent"
android:layout_marginTop="18dp">
<RadioButton
android:text="Male"
android:layout_width="wrap_content"
android:layout_height="wrap_content" tools:layout_editor_absoluteY="328dp"
tools:layout_editor_absoluteX="58dp" android:id="#+id/male"/>
<RadioButton
android:text="Female"
android:layout_width="wrap_content"
android:layout_height="wrap_content" tools:layout_editor_absoluteY="328dp"
tools:layout_editor_absoluteX="224dp" android:id="#+id/radioButton4"/>
</RadioGroup>
I've looked through the docs of RadioGroup and getCheckedRadioButtonId seems to be the most appropriate function to use:
Returns the identifier of the selected radio button in this group.
Upon empty selection, the returned value is -1.
However it returns a useless Int and not the id of the RadioButton:
import kotlinx.android.synthetic.main.activity_player_details.*
override fun onClick(v: View?) {
val name: String = player_name.text.toString()
val age: Int = player_age.text.toString().toInt()
val gender: Int = gender.checkedRadioButtonId
println(name)
println(age)
println(gender) // prints 2131361895
}
}
Any idea how I can retrieve the actual id of the checked RadioButton?
In a layout file, the attribute android:id="#+id/male" means "use the id constant named 'male,' and create it if it does not exist". This causes an int to be generated in the R.java R.id class; if you go look at the actual value of the field R.id.male, you will see that it is some seemingly-random number.
When you use R.id.male from java code, you are in fact just using some int value. So when you get the checked id, and print it, it makes sense to see a "random" number.
However, you can resolve the number back to a String representing the name by using the Resources.getResourceEntryName() method:
val genderId = gender.checkedRadioButtonId // R.id.male, int value 2131361895
val genderString = resources.getResourceEntryName(genderId) // "male"