How to get the default value of radio button from database?

Question

I have 5 check-box. For each check-box, 5 radio buttons get generated. These radios value get saved to database. Now what I want is, when I select check-box, and if the selected check-box has some database value already saved in database, that radio button should show saved database value, mean to say, it should be shown selected. 5 check-box are like: 1. A 2. B 3. C 4. D 5. C

All check-box has radio options like: Male or Female

If(say) I choose "Male" for "A" and submit my form. when I again go to that form and choose "A", "male" radio button should be shown selected.

some code implementation:

foreach ($check-box-options as $key => $value) {

        $form['radio_'.$key] = array(
            '#type' => 'radios',
            '#title' => t('abc'),
            '#options' => $filter_radio_options,
            '#default_value'=> ???,
            '#states' => array(
                'visible' => array(
                    ':input[name="filter_criteria_options['.$key.']"]' => array('checked' => TRUE),
                ),
            ),
        );
}

$check-box-options is an array of check-box A,B,C,D,E. For each check-box, I have radios.

$serialized = unserialize($radio_buttons_database_values);

$serialized contains all selected radio button values. If I replace $check-box-options with $serialized, I got correct radio button selected as default, but if I loop $serialized as nested inside $check-box-options, it is throwing last selected value from database for every check-box. I am not getting the exact problem with my code or approach.

Can anyone please help me understanding the exact problem behind this?

Answer 1

As the radios are separate field in itself, default value should be as easy as follow

foreach ($check-box-options as $key => $value) {
        //A. A function to query database to get default value
        $default_value = _my_module_helper_get_default_radio_option($key);

        //B. Or if its a system setting form, all values are inside the variables, in that case all you have to do is variable_get()
        $default_value = variable_get('radio_'.$key);

        // Depending on form type use option A or B.

        $form['radio_'.$key] = array(
            '#type' => 'radios',
            '#title' => t('abc'),
            '#options' => $filter_radio_options,
            '#default_value'=> $default_value,
            '#states' => array(
                'visible' => array(
                    ':input[name="filter_criteria_options['.$key.']"]' => array('checked' => TRUE),
                ),
            ),
        );
}

// In case option A is what you needed.
function _my_module_helper_get_default_radio_option($key) {
  return db_select('your_table','yt')
         ->fields('yt',array('field_name'))
         ->condition('yt.field_is',$key,'=')
         ->exectue()
         ->fetchField();

 }