[android] How to check if a radiobutton is checked in a radiogroup in Android?

I need to set validation that user must fill / select all details in a page. If any fields are empty wanna show Toast message to fill. Now I need set validation for RadioButton in the RadioGroup. I tried this code but didn't work properly. Suggest me correct way. Thankyou.

// get selected radio button from radioGroup
int selectedId = gender.getCheckedRadioButtonId();
// find the radiobutton by returned id
selectedRadioButton = (RadioButton)findViewById(selectedId);
// do what you want with radioButtonText (save it to database in your case)
radioButtonText = selectedRadioButton.getText().toString();

if(radioButtonText.matches(""))
{
    Toast.makeText(getApplicationContext(), "Please select Gender", Toast.LENGTH_SHORT).show();
    Log.d("QAOD", "Gender is Null");
}
else
{
    Log.d("QAOD", "Gender is Selected");
}

I used the id's of my radiobuttons to compare with the id of the checkedRadioButton that I got using mRadioGroup.getCheckedRadioButtonId()

Here is my code:

mRadioButton1=(RadioButton)findViewById(R.id.first);
mRadioButton2=(RadioButton)findViewById(R.id.second);
mRadioButton3=(RadioButton)findViewById(R.id.third);
mRadioButton4=(RadioButton)findViewById(R.id.fourth);

mNextButton=(Button)findViewById(R.id.next_button);

mNextButton.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        int selectedId=mRadioGroup.getCheckedRadioButtonId();

        int n=0;
        if(selectedId==R.id.first){n=1;}

        else if(selectedId==R.id.second){n=2;}

        else if(selectedId==R.id.third){n=3;}

        else if(selectedId==R.id.fourth){n=4;}
        //. . . .
    }

My answer is according to the documentation, which works fine.

1) In xml file include android:onClick="onRadioButtonClicked" as shown below:

<RadioGroup
android:id="@+id/rg1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:gravity="center">
<RadioButton
    android:id="@+id/b1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="onCreateOptionsMenu()"
    android:onClick="onRadioButtonClicked"
            />
<RadioButton
    android:id="@+id/b2"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="onCreateMenu()"
    android:onClick="onRadioButtonClicked"
            />
</RadioGroup>

2) In Java file implement onRadioButtonClicked method outside onCreate() method as shown below:

public void onRadioButtonClicked(View view) {
    // Is the button now checked?
    boolean checked = ((RadioButton) view).isChecked();

    // Check which radio button was clicked
    switch(view.getId()) {
        case R.id.b1:
            if (checked)
            {
                Log.e("b1", "b1" );
                break;
            }
        case R.id.b2:
            if (checked)
                break;
    }
}

  rgrp.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup radioGroup, int i) {
            switch(i) {
                case R.id.type_car:
                    num=1;
                    Toast.makeText(getApplicationContext()," Car",Toast.LENGTH_LONG).show();
                    break;
                case R.id.type_bike:
                    num=2;
                    Toast.makeText(getApplicationContext()," Bike",Toast.LENGTH_LONG).show();
                    break;
            }
        }
    });

All you need to do is use getCheckedRadioButtonId() and isChecked() method,

if(gender.getCheckedRadioButtonId()==-1)
{
    Toast.makeText(getApplicationContext(), "Please select Gender", Toast.LENGTH_SHORT).show();
}
else
{
    // get selected radio button from radioGroup
    int selectedId = gender.getCheckedRadioButtonId();
    // find the radiobutton by returned id
    selectedRadioButton = (RadioButton)findViewById(selectedId);
    Toast.makeText(getApplicationContext(), selectedRadioButton.getText().toString()+" is selected", Toast.LENGTH_SHORT).show();
}

https://developer.android.com/guide/topics/ui/controls/radiobutton.html

Try to use the method isChecked();

Like,

selectedRadioButton.isChecked() -> returns boolean.

Refere here for more details on Radio Button

I used the following and it worked for me. I used a boolean validation function where if any Radio Button in a Radio Group is checked, the validation function returns true and a submission is made. if returned false, no submission is made and a toast to "Select Gender" is shown:

1. MainActivity.java

   public class MainActivity extends AppCompatActivity {
       private RadioGroup genderRadioGroup;
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main);
   
       //Initialize Radio Group And Submit Button
       genderRadioGroup=findViewById(R.id.gender_radiogroup);
       AppCompatButton submit = findViewById(R.id.btnSubmit);
   
       //Submit Radio Group using Submit Button
       submit.setOnClickListener(new View.OnClickListener() {
           @Override
           public void onClick(View v) {
               //Check Gender radio Group For Selected Radio Button
               if(genderRadioGroup.getCheckedRadioButtonId()==-1){//No Radio Button Is Checked
                   Toast.makeText(getApplicationContext(), "Please Select Gender", Toast.LENGTH_LONG).show();
               }else{//Radio Button Is Checked
                   RadioButton selectedRadioButton = findViewById(genderRadioGroup.getCheckedRadioButtonId());
                   gender = selectedRadioButton == null ? "" : selectedRadioButton.getText().toString().trim();
               }
               //Validate
               if (validateInputs()) {
                   //code to proceed when Radio button is checked
               }
           }
       }
       //Validation - No process is initialized if no Radio button is checked
       private boolean validateInputs() {
           if (genderRadioGroup.getCheckedRadioButtonId()==-1) {
               return false;
           }
           return true;
       }
   }
   

2. In activity_main.xml:

   <LinearLayout
           android:layout_width="match_parent"
           android:layout_height="wrap_content"
           android:orientation="horizontal">
   
       <TextView
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"
               android:text="@string/gender"/>
   
       <RadioGroup
               android:id="@+id/gender_radiogroup"
               android:layout_width="wrap_content"
               android:layout_height="wrap_content"
               android:orientation="horizontal">
   
           <RadioButton
                   android:id="@+id/male"
                   android:layout_width="wrap_content"
                   android:layout_height="wrap_content"
                   android:text="@string/male"/>
   
           <RadioButton
                   android:id="@+id/female"
                   android:layout_width="wrap_content"
                   android:layout_height="wrap_content"
                   android:text="@string/female""/>
   
       </RadioGroup>
   
       <android.support.v7.widget.AppCompatButton
           android:id="@+id/btnSubmit"
           android:layout_width="match_parent"
           android:layout_height="wrap_content"
           android:text="@string/submit"/>
   
   </LinearLayout>
   

If no gender radio button is selected, then the code to proceed will not run.

I hope this helps.

Use the isChecked() function for every radioButton you have to check.

RadioButton maleRadioButton, femaleRadioButton;

maleRadioButton = (RadioButton) findViewById(R.id.maleRadioButton);
femaleRadioButton = (RadioButton) findViewById(R.id.femaleRadioButton);

Then use the result for your if/else case consideration.

if (maleRadioButton.isChecked() || femaleRadioButton.isChecked()) {
     Log.d("QAOD", "Gender is Selected");
} else {
    Toast.makeText(getApplicationContext(), "Please select Gender", Toast.LENGTH_SHORT).show();
    Log.d("QAOD", "Gender is Null");
}

mRadioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup radioGroup, int i) {
            if (mRadioButtonMale.isChecked()) {
                text = "male";
            } else {
                text = "female";
            }
        }
    });

OR

 mRadioGroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup radioGroup, int i) {
            if (mRadioButtonMale.isChecked()) { text = "male"; }
            if(mRadioButtonFemale.isChecked()) { text = "female"; }
        }
    });

try to use this

<RadioGroup
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"       
    android:orientation="horizontal"
>    
    <RadioButton
        android:id="@+id/standard_delivery"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/Standard_delivery"
        android:checked="true"
        android:layout_marginTop="4dp"
        android:layout_marginLeft="15dp"
        android:textSize="12dp"
        android:onClick="onRadioButtonClicked"   
    />

    <RadioButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/Midnight_delivery"
        android:checked="false"
        android:layout_marginRight="15dp"
        android:layout_marginTop="4dp"
        android:textSize="12dp"
        android:onClick="onRadioButtonClicked"
        android:id="@+id/midnight_delivery"
    />    
</RadioGroup>

this is java class

public void onRadioButtonClicked(View view) {
        // Is the button now checked?
        boolean checked = ((RadioButton) view).isChecked();

        // Check which radio button was clicked
        switch(view.getId()) {
            case R.id.standard_delivery:
                if (checked)
                    Toast.makeText(DishActivity.this," standard delivery",Toast.LENGTH_LONG).show();
                    break;
            case R.id.midnight_delivery:
                if (checked)
                    Toast.makeText(DishActivity.this," midnight delivery",Toast.LENGTH_LONG).show();
                    break;
        }
    }