title: How to check if a radiobutton is checked in a radiogroup in Android?
body: <p>I need to set validation that user must fill / select all details in a page. If any fields are empty wanna show <code>Toast message to fill.</code> Now I need set validation for <code>RadioButton</code> in the <code>RadioGroup.</code> I tried this code but didn't work properly. Suggest me correct way. Thankyou.</p>
  
  <pre><code>// 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");
  }
  </code></pre>