Develop Reference

How to find out selected radio option, when android:radiobutton="#null" in android?

I am creating a set of radio options where the radio buttons are removed, and I would like to know which option is selected.
Here is the code
<RadioGroup
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="200dp"
android:orientation="horizontal"
android:gravity="center_horizontal"
android:id="#+id/languages"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true">
<RadioButton
android:id="#+id/english"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingRight="20dp"
android:text="#string/langtext_english"
android:textSize="16dp"
android:checked="true"
android:button="#null" />
<RadioButton
android:id="#+id/bahasaIndonesia"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/langtext_indonesian"
android:textSize="16dp"
android:button="hide"/>
</RadioGroup>
I don't want to show the radio button, but I would like to know which option is selected. onCheckedChangedListener doesn't work as there is no button. How to do this?
When the option is touched or clicked, I would like to show a Toast.
View rootView = inflater.inflate(R.layout.fragment_home, container, false);
langChosen = (RadioGroup) rootView.findViewById(R.id.languages);
langChosen.setOnClickListener(new RadioGroup.OnClickListener() {
#Override
public void onClick(View v) {
Toast abc = new Toast(getContext());
abc.makeText(getContext(), v.toString(),Toast.LENGTH_LONG);
}

You mentioned
I don't want to show the radio button, but I would like to know which option is selected. onCheckedChangedListener doesn't work as there is no button.
I would not say that is true. The RadioGroup still registers changes of the checked radio button. The android:button attribute of RadioButtonjust represents the button you see next to the text/content of the radio button. You still can register to click events of the radio button element itself.
Could it be that you just forgot to call show() on your toast, so you think it's not working?
I supply a tested solution for you here. Let me know if it works for you too.
RadioGroup group = (RadioGroup)this.findViewById(R.id.languages);
group.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
RadioButton b = (RadioButton)findViewById(radioGroup.getCheckedRadioButtonId());
Toast.makeText(MainActivity.this, b.getText(), Toast.LENGTH_SHORT).show();
}
});
Note that MainActivity.this must be replaced with your corresponding context.

I would try the OnClick method with the two buttons, then the method is called, use the ischecked() method to detremine which of the buttons is checked.

ToggleButton group in complex layout

Supposed that I have a view structure like this:
<TableLayout>
<TableRow>
<ToggleButton />
<ToggleButton />
<ToggleButton />
</TableRow>
<TableRow>
<ToggleButton />
<ToggleButton />
<ToggleButton />
</TableRow>
</TableLayout>
My goal is to make toggle buttons act as group of radio button. There were a lots of answer on SOF saying that using RadioGroup. I tried some, they work but not as expected since they break TableRow's formats, say: column fixed width. Then I decided to use a recursive method to check & reset toggle button state as of below:
private void resetChildState(ViewGroup parent, int target) {
int count = parent.getChildCount();
for (int i = 0; i < count; i++) {
View child = parent.getChildAt(i);
if (child instanceof TableRow) {
resetChildState((ViewGroup)child, target);
} else if (child instanceof ToggleButton) {
if ((int)child.getTag() != target) {
((ToggleButton) child).setChecked(false);
}
}
}
}
This works, but another problem came. The respond time is too bad since there were too much work on main thread which resulted in some laggy behaviors.
My question is: is there any other better approach for my situation?

Keep a list of just the ToggleButtons and iterate over that to reset them. Then you won't need to iterate over the entire view hierarchy.

Set default checked Radio Button

I'm creating a RadioGroup with RadioButtons dynamically and need to have one radio button checked by default.
I've done this by using both radioButton.setChecked(true) and radioButton.toggle();
The problem I have is that when I at runtime select another radio button the first one stays checked so I end up with two checked radio buttons in the radio group.
Has anyone had this problem and know how to solve it?
private RadioButton addRadioButton(String type, String price){
RadioButton radio = new RadioButton(Order.this);
radio.setText(type + " (" + Utils.formatCurrency(price) + ")");
radio.setTextAppearance(Order.this, R.style.portalCellTextStyle);
radio.setTextSize(TypedValue.COMPLEX_UNIT_SP, 10);
radio.setTag(price);
if(type.toLowerCase().equals("m"))
radio.toggle();
return radio;
}

I know I'm late but for those who search for the answer like me this can be useful.
When you add RadioButton to a RadioGroup, you must set the button checked after adding it to the parent like:
RadioGroup radioGroup = new RadioGroup(getContext())
RadioButton radioButton = new RadioButton(getContext());
radioButton.setText("text");
mRadioGroup.addView(radioButton);
radioButton.setChecked(true);
If the view is checked before adding it to the parent, it will be impossible to uncheck it.

You can do this simply:
JAVA:
radiogroup =(RadioGroup)findViewById(R.id.radiogroup);
radiobutton1 =(RadioButton)findViewById(R.id.radiobutton1);
radiobutton2 =(RadioButton)findViewById(R.id.radiobutton2);
if(your first assessment){
radiobutton1.setChecked(true);
}else{
radiobutton2.setChecked(true);
}
XML:
<RadioGroup
android:id="#+id/radiogroup"
android:orientation="horizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
android:id="#+id/radiobutton1"
android:checked="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<RadioButton
android:id="#+id/radiobutton2"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RadioGroup>

Simple, at first time load the screen check the position of In Getview method and then apply condition:
if (position == 0) {
holder.act_delivery_rbtn.setChecked(true);
}

If you are only using one radio box for checking on and off, maybe you should use checkbox or toggle button instead.
http://developer.android.com/resources/tutorials/views/hello-formstuff.html
Scroll down and see checkbox and toggle button.
When using radios you usually have more than one and choose between them. Like easy, medium, hard.
Replace
radio.toggle();
with
radio.setChecked(true);

Just make checked = "true" in your code

you should check it in radio group...
radiogroup.check(IdOfYourButton)

use the clearCheck () function to clear the already checked buttons.I hope this solves your problem.

Turned out to be because I called the checked() method on the radio group straight after setting the OnCheckedChangeListener() causing it to be called immediately and throw a NPE for some reason.
Moved the checked() method call to just before the OnCheckedChangeListener() and it works now.
radios.check(2);
radios.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
}
});
private RadioButton addRadioButton(String type, String price){
RadioButton radio = new RadioButton(Order.this);
radio.setText(type + " (" + Utils.formatCurrency(price) + ")");
radio.setTextAppearance(Order.this, R.style.portalCellTextStyle);
radio.setTextSize(TypedValue.COMPLEX_UNIT_SP, 10);
radio.setTag(price);
if(type.toLowerCase().equals("m"))
radio.setId(2);
return radio;
}

in Xml add android:checkedButton="#+id/storeRB" to RadioGroup
<RadioGroup
android:id="#+id/storeTypeRG"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:checkedButton="#+id/storeRB"
android:orientation="horizontal"
app:layout_constraintBottom_toBottomOf="#+id/text2"
app:layout_constraintStart_toEndOf="#+id/text2"
app:layout_constraintTop_toTopOf="#+id/text2">
<RadioButton
android:id="#+id/storeRB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="24dp"
android:button="#drawable/radio_button_bg"
android:paddingStart="8dp"
android:text="#string/store_str"
app:layout_constraintBottom_toBottomOf="#+id/text2"
app:layout_constraintStart_toEndOf="#+id/text2"
app:layout_constraintTop_toTopOf="#+id/text2" />
<RadioButton
android:id="#+id/hyperRB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:button="#drawable/radio_button_bg"
android:paddingStart="8dp"
android:text="#string/hyper_str"
app:layout_constraintBottom_toBottomOf="#+id/text2"
app:layout_constraintStart_toEndOf="#+id/storeRB"
app:layout_constraintTop_toTopOf="#+id/text2" />
<RadioButton
android:id="#+id/restaurantRB"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:button="#drawable/radio_button_bg"
android:paddingStart="8dp"
android:text="#string/restaurant_str"
app:layout_constraintBottom_toBottomOf="#+id/text2"
app:layout_constraintStart_toEndOf="#+id/hyperRB"
app:layout_constraintTop_toTopOf="#+id/text2" />
</RadioGroup>

Unchecking a radio button [duplicate]

This question already has answers here:
Android radio button uncheck
(6 answers)
Closed 2 years ago.
The application is a step sequencer application with 16 radio groups with 8 buttons in each group. It works perfectly except once a group has a button selected I cant turn it off unless I use the clear button I have created to clear all radiogroups. What I would like to add is some code that says when a selected radio button is selected again it simply turns off like a toggle. I tried using toggles but then other issues arose with that method. Below is an attempt at it but it is way off the mark Im guessing
final RadioGroup radioGroup1 = (RadioGroup)findViewById(R.id.RadioGroup1);
RadioButton lC1 = (RadioButton)findViewById(R.id.RadioButtonlowC1);
Button D1 = (Button)findViewById(R.id.RadioButtonD1);
D1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
PdBase.sendFloat("D1", 74);
int selectedTypeId = radioGroup1.getCheckedRadioButtonId();
RadioButton D1 = (RadioButton) findViewById(selectedTypeId);
if(radioGroup1 != null) // This will be null if none of the radio buttons are selected
radioGroup1.clearCheck();
PdBase.sendFloat("D1", 0);
}
});

You need to put the button in a radio group, then clear the group. A radio button can't be unchecked directly, because the idea is that one option in a group is always checked.

Here is an example of how to create radiogroup, radiobutton and how to use in Java code. Hope it will give you complete picture
XML file:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<RadioGroup
android:id="#+id/maptype"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/line1"
android:orientation="horizontal" >
<RadioButton
android:id="#+id/map"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:checked="true"
android:drawableRight="#drawable/ic_launcher"/>
<RadioButton
android:id="#+id/satellite"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:drawableRight="#drawable/ic_launcher"/>
</RadioGroup>
</LinearLayout>
In Java Code
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
RadioGroup rgrpMapType = (RadioGroup) findViewById(R.id.maptype);
int selectedTypeId = rgrpMapType.getCheckedRadioButtonId();
RadioButton rbMapType = (RadioButton) findViewById(selectedTypeId);
if(rbMapType != null) // This will be null if none of the radio buttons are selected
rgrpMapType.clearCheck();
}

Set selected index of an Android RadioGroup

Is there a way to set the selected index of a RadioGroup in android, other than looping through the child radiobuttons and selecting checking the radio button at the selected index?
Note: I am populating the Radio Button Group at run time.

If your radio group is defined in a layout xml file, each button can be assigned an id. Then you just check a button like this
radioGroup.check(R.id.myButtonId);
If you created your radio group programmatically (I'm not even sure how you do this...), you might want to consider creating a special layout xml file just for the radio group so that you can assign R.id.* ids to the buttons.
Please see the answer below if you are, in fact, looking to set the radio button group by index, see the answer below.
((RadioButton)radioGroup.getChildAt(index)).setChecked(true);

Question said "set selected INDEX", here's how to set it by index:
((RadioButton)radioGroup.getChildAt(index)).setChecked(true);
........
Additional info: It seems that Google wants you to use id instead of index, because using id is more bug proof. For example, if you have another UI element in your RadioGroup, or if another developer re-orders the RadioButtons, the indices might change and not be what you expected. But if you're the only developer, this is totally fine.

you can do findViewById from the radio group .
((RadioButton)my_radio_group.findViewById(R.id.radiobtn_veg)).setChecked(true);`

Siavash's answer is correct:
((RadioButton)radioGroup.getChildAt(index)).setChecked(true);
But be aware that a radioGroup can contain views other than radioButtons -- like this example that includes a faint line under each choice.
<RadioGroup
android:id="#+id/radioKb"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<RadioButton
android:id="#+id/kb1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:button="#null"
android:drawableRight="#android:drawable/btn_radio"
android:text="Onscreen - ABC" />
<View
android:layout_width="fill_parent"
android:layout_height="1dp"
android:background="#33000000" />
<RadioButton
android:id="#+id/kb2"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:button="#null"
android:drawableRight="#android:drawable/btn_radio"
android:text="Onscreen - Qwerty" />
<View
android:layout_width="fill_parent"
android:layout_height="1dp"
android:background="#33000000" />
<RadioButton
android:id="#+id/kb3"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:button="#null"
android:drawableRight="#android:drawable/btn_radio"
android:text="Standard softkey" />
<View
android:layout_width="fill_parent"
android:layout_height="1dp"
android:background="#33000000" />
<RadioButton
android:id="#+id/kb4"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:button="#null"
android:drawableRight="#android:drawable/btn_radio"
android:text="Physical keyboard" />
<View
android:layout_width="fill_parent"
android:layout_height="1dp"
android:background="#33000000" />
</RadioGroup>
In this case using an index of 1, for example, would generate an error. The item at index 1 is the first separator line -- not a radioButton. The radioButtons in this example are at indexes 0, 2, 4, 6.

This Worked For me, I created radio button dynamically by
private void createRadioButton() {
RadioButton[] rb = new RadioButton[5];
RadioGroup.LayoutParams layoutParams = new RadioGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT,
1.0f);
radioGroup.setOrientation(RadioGroup.HORIZONTAL);
for (int ID = 0; ID < 5; ID++) {
rb[ID] = new RadioButton(this);
rb[ID].setLayoutParams(layoutParams);
rb[ID].setText("Button_Text");
radioGroup.addView(rb[ID]); //the RadioButtons are added to the radioGroup instead of the layout
}
}
Now Check a button using,
int radio_button_Id = radioGroup.getChildAt(index).getId();
radioGroup.check( radio_button_Id );

Inside onBindViewHolder set the tag to Button Group
#Override
public void onBindViewHolder(final CustomViewHolder holder, final int position) {
...
holder.ButtonGroup.setTag(position);
}
and in the ViewHolder
ButtonGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(RadioGroup radioGroup, int checkedId) {
...
int id = radioGroup.getCheckedRadioButtonId();
RadioButton radioButton = (RadioButton) radioGroup.findViewById(id);
int clickedPos = (Integer) radioGroup.getTag();
packageModelList.get(clickedPos).getPoll_quest()
}

Using Kotlin you can make it by
(radio_group_id.getChildAt(index) as RadioButton).isChecked = true
or
radio_group_id.check(R.id.radio_button_id)