Android ListView with RadioButton in singleChoice mode and a custom row layout

Do bear in mind that in the ListView row items are RECYCLED. This is likely to explain why actions on one row are affecting another. Dig around in Mark's book and you'll find coverage of this.

If you're using an adapter with the list, you can use getView() on an adapter to add a click handler to each row as it's created/recycled, and make sure the state is managed correctly as the row items are created and recycled.

My approach is to store the state in my own data structure, and then use getView() to mirror that in the UI as the user scrolls up and down the ListView. There may be a better solution, but that works for me.

Simple solution:

Add this line in the RadioButton layout of your xml file:

<RadioButton 
   ...
   android:onClick="onClickRadioButton"
   ...
/>

Then in the activity class that uses the ListView, add the following:

   private RadioButton listRadioButton = null;
   int listIndex = -1;

   public void onClickRadioButton(View v) {
        View vMain = ((View) v.getParent());
        // getParent() must be added 'n' times, 
        // where 'n' is the number of RadioButtons' nested parents
        // in your case is one.

        // uncheck previous checked button. 
        if (listRadioButton != null) listRadioButton.setChecked(false);
        // assign to the variable the new one
        listRadioButton = (RadioButton) v;
        // find if the new one is checked or not, and set "listIndex"
        if (listRadioButton.isChecked()) {
            listIndex = ((ViewGroup) vMain.getParent()).indexOfChild(vMain); 
        } else {
            listRadioButton = null;
            listIndex = -1;
        }
    }

With this simple code only one RadioButton is checked. If you touch the one that is already checked, then it returns to the unchecked mode.

"listIndex" is tracking the checked item, -1 if none.

If you want to keep always one checked, then code in onClickRadioButton should be:

   public void onClickRadioButton(View v) {
        View vMain = ((View) v.getParent());
        int newIndex = ((ViewGroup) vMain.getParent()).indexOfChild(vMain);
        if (listIndex == newIndex) return;

        if (listRadioButton != null) {
                listRadioButton.setChecked(false);
        }
        listRadioButton = (RadioButton) v;
        listIndex = newIndex; 
    }