[b]Thank you for the quick answers.
This helps me well.[/b]

In addition to the resources posted by drakinite you can also have a look at the dev branch in the [url=https://github.com/mmuffins/mediamonkey-codemonkey/tree/dev]code monkey repository[/url] for a full implementation. I recently finished adding the new color picker which also utilizes some things you asked about like reading and writing settings and less values.

qid('SkinFontSize').controlClass.value = '10'

var UI = getAllUIElements();
UI.SkinFontSize.controlClass.value = '10';

var UI = getAllUIElements();
var myFontSize = UI.SkinFontSize.controlClass.value + 'px';
setLessValues({ baseFontSize: myFontSize }, 'DarkSilver');

Firstly: if you wish to set a dropdown's default value, the simplest way to do it is via the [b]value[/b] property from JavaScript. (https://www.mediamonkey.com/docs/api/classes/Dropdown.html#property_value)

For example, if you wish to set the default value to 10, you would do either of the following:

[code]qid('SkinFontSize').controlClass.value = '10'[/code]
or
[code]var UI = getAllUIElements();
UI.SkinFontSize.controlClass.value = '10';[/code]

Secondly: If you wish for the value to be [i]saved[/i] after the user changes their setting, you can use [b]app.getValue[/b] and [b]app.setValue[/b]. https://www.mediamonkey.com/docs/api/classes/App.html#method_getValue There are plenty of addons that utilize this method for saving user preferences, including the Monkey Groove skin in recent beta builds.

Thirdly: To set LESS variables from JavaScript, there is a new method [b]setLessValues[/b] in 5.0.2 beta builds which will let you do it: https://www.mediamonkey.com/docs/api/classes/Window.html#method_setLessValues
The first argument to pass is an object with the variable names and values. The second argument is your skin's ID. In your case, that would be "DarkSilver". [u]If you do NOT specify a skin ID, this will set LESS values for ALL skins.[/u]

So here's an example of how you could implement it, in your config file's [b]save[/b] function:
[code]
var UI = getAllUIElements();
var myFontSize = UI.SkinFontSize.controlClass.value + 'px';
setLessValues({ baseFontSize: myFontSize }, 'DarkSilver');
[/code]

(P.S. Please note that there [b]are[/b] future plans to make it easier for skin developers to make customizable settings, without having to create a config.js and config.html. However, I do not know when it will be ready.)

<div data-id="SkinFontSize" data-control-class="Dropdown" data-init-params="{readOnly: true,preload: true}" class="dropdown">
    <option>10</option>
    <option>11</option>
    <option>12</option>
</div>

Hello, and please excuse me,
for my bad English, my native language is German.

I would like to add a font-size setting for my skin.
I would like to achieve this setting in MM5 under Options\Design.

I have already written or edited the corresponding file "config.html & config.js"
several times. I just can't get it to work.
The dropdown in config.html is created and also works.

[code]
<div data-id="SkinFontSize" data-control-class="Dropdown" data-init-params="{readOnly: true,preload: true}" class="dropdown">
<option>10</option>
<option>11</option>
<option>12</option>
</div>
[/code]


Question, how do I set a default value, the dropdown menu is always empty ?
The entries are only displayed when you select them.

Question, how should I proceed in config.js to read the @baseFontSize variable,
and read the value from the dropdown menu and write it to the @baseFontSize variable.

I have searched all the MM5 help files and the forum, but have not found a solution.
An answer would be nice, thank you