When edittext is null then ok button will be disabled and as soon as the text is entered it will be enabled::
public class CustomEditTextPreference extends EditTextPreference implements
OnClickListener {
public CustomEditTextPreference(Context ctx, AttributeSet attrs, int defStyle)
{
super(ctx, attrs, defStyle);
}
public CustomEditTextPreference(Context ctx, AttributeSet attrs)
{
super(ctx, attrs);
}
private class EditTextWatcher implements TextWatcher
{
@Override
public void onTextChanged(CharSequence s, int start, int before, int count){}
@Override
public void beforeTextChanged(CharSequence s, int start, int before, int count){}
@Override
public void afterTextChanged(Editable s)
{
onEditTextChanged();
}
}
EditTextWatcher m_watcher = new EditTextWatcher();
/**
* Return true in order to enable positive button or false to disable it.
*/
protected boolean onCheckValue(String value)
{
if (value.trim().equals(""))
{
return false;
}
return true;
}
protected void onEditTextChanged()
{
boolean enable = onCheckValue(getEditText().getText().toString());
Dialog dlg = getDialog();
if(dlg instanceof AlertDialog)
{
AlertDialog alertDlg = (AlertDialog)dlg;
Button btn = alertDlg.getButton(AlertDialog.BUTTON_POSITIVE);
btn.setEnabled(enable);
}
}
@Override
protected void showDialog(Bundle state)
{
super.showDialog(state);
getEditText().removeTextChangedListener(m_watcher);
getEditText().addTextChangedListener(m_watcher);
onEditTextChanged();
}
}