[sualfred]

You could offer a set of possible integers. Like a range from 5 to 60.

Code:


<?xml version="1.0" encoding="UTF-8"?>
<window type="dialog" id="1116">
    <visible>
        [Window.IsVisible(musicosd) | Window.IsVisible(videoosd)] + [
        [System.IdleTime(30) + String.IsEqual(Skin.String(mytimer),30)]
        | [System.IdleTime(20) + String.IsEqual(Skin.String(mytimer),20)]
        | [System.IdleTime(10) + String.IsEqual(Skin.String(mytimer),10)]
        | [System.IdleTime(5) + String.IsEqual(Skin.String(mytimer),5)]
        ]
    </visible>
    <onload>Dialog.Close(videoosd)</onload>
    <onload>Dialog.Close(musicosd)</onload>
    <controls/>
</window>


or

Code:


<?xml version="1.0" encoding="UTF-8"?>
<window type="dialog" id="1116">
    <visible>
        [Window.IsVisible(musicosd) | Window.IsVisible(videoosd)] + System.IdleTime(1)
    </visible>
    <onload condition="String.IsEqual(Skin.String(mytimer),5)">AlarmClock(closetimer,Dialog.Close(videoosd),00:04,silent)</onload>
    <onload condition="String.IsEqual(Skin.String(mytimer),5)">AlarmClock(closetimer,Dialog.Close(musicosd),00:04,silent)</onload>
    <onload condition="String.IsEqual(Skin.String(mytimer),10)">AlarmClock(closetimer,Dialog.Close(videoosd),00:09,silent)</onload>
    <onload condition="String.IsEqual(Skin.String(mytimer),10)">AlarmClock(closetimer,Dialog.Close(musicosd),00:09,silent)</onload>
    <onload condition="String.IsEqual(Skin.String(mytimer),20)">AlarmClock(closetimer,Dialog.Close(videoosd),00:19,silent)</onload>
    <onload condition="String.IsEqual(Skin.String(mytimer),20)">AlarmClock(closetimer,Dialog.Close(musicosd),00:19,silent)</onload>
    <controls/>
</window>


Edit:
The reason why I always prefer to use a skin method like this is that each service and continuously Python call for conditions each second is expensive.