Select dropdown not showing selected value php

Question

I'm using Wordpress Settings API. Everything works as it should except this select dropdown. When I select an option, the value echoed is correct but in the dropdown it displays the default first value i.e 6 and not the selected one. Where am I going wrong?

 public function someplugin_select() {
            $options = get_option( 'plugin_252calc');
            echo $options; //shows the correct value selected
            $items = array();
            for ($i=6; $i <=10; $i+= 0.1) 
            { 
                $items[] = $i;
            }

            echo '<select id="cf-nb" name="cf-nb">';
            foreach ( $items as $item )
            {
                echo '<option value="'. $item .'"';
                if ( $item == $options ) echo' selected="selected"';
                echo '>'. $item .'</option>';
            }

            echo '</select>';           

        }

Answer 1

The reason your $item == $option condition is always failing is because of the way PHP compares floats!

Try the following instead:

echo "<option value='$item'" . selected (abs ($item - $options) <= 0.01, true, false) . ">$item</option>" ;

See Comparing floats for more info.

Answer 2

I went through this, and I could tell that there's a WP function called selected, which you can see in this link. Use this function instead of doing: if ( $item == $options ). And your code could look like this:

foreach ( $seconds as $second => $time ) {
   ?>
      <option value="<?php echo $second; ?>" <?php selected( $browser_cache_ttl, $second ); ?>><?php echo $time; ?></option>
   <?php
}

So that function loops through $seconds and get the $second and $time, put te $second as value, then call the selected function which the first parameter is the value to compare and the second one is the current value, if those values are the same, it'll be selected.

I think that's what you're looking for. Tell me if it worked.

Answer 3

Replace your select with this... Hope it works...

        echo '<select id="cf-nb" name="cf-nb">';
        foreach ( $items as $item ){
            $if_selected = $item == $options ? "selected='selected'" : "";
            echo "<option value='{$item}' {$if_selected}>$item</option>";

        }

        echo '</select>'; 

Answer 4

I don't have any better answers, but I feel I have a similar-enough issue to add to this question instead of making a new one.

I started with https://www.youtube.com/watch?v=hbJiwm5YL5Q&t=3969s and got as far as 1:05:00 and this is my current version is

function selectpageHTML() {?>
            <select name="lp_actPage"> 
                <?
                    $pages = get_pages();                       foreach ( $pages as $page ) {                               
                                $title = $page->post_title;
                                echo "<option value='$title'" . selected(get_option('lp_actPage', $title)) .">$title</option>";
                                } ?>
            </select>
        <?}

however, instead of comparing floats I was thinking I could compare string values instead, but so far no dice.

I also tried assigning a variable as the page ID and using that variable as the option value as well as the 2nd argument in the get_option() function, but still no joy.