Skin Variables / Conditional Labels

**pieh** · 2011-08-15 01:34

It was often mentioned - now it's about time to get it done.

This is now just discussion - it's not done yet

Skin variables are meant to get rid of multiples controls differing only by value of <texture> / <label> depending on <visible> condition.
Good example of its use are media flags (I'll use video type based on filename - bluray / hddvd / dvd / tv / vhs):

Currently this is done:

Code:

<include name="VideoTypeHackFlaggingConditions">

    <control type="image">

        <description>Bluray Image</description>

        <width>80</width>

        <height>35</height>

        <aspectratio align="left">keep</aspectratio>

        <texture>flagging/video/bluray.png</texture>

        <visible>[substring(ListItem.FilenameAndPath,bluray) | substring(ListItem.FilenameAndPath,bdrip)] + !Skin.HasSetting(HideFilenameFlagging)</visible>

    </control>

    <control type="image">

        <description>HDDVD Image</description>

        <width>80</width>

        <height>35</height>

        <aspectratio align="left">keep</aspectratio>

        <texture>flagging/video/hddvd.png</texture>

        <visible>substring(ListItem.FilenameAndPath,hddvd) + !Skin.HasSetting(HideFilenameFlagging)</visible>

    </control>

    <control type="image">

        <description>DVD Image</description>

        <width>80</width>

        <height>35</height>

        <aspectratio align="left">keep</aspectratio>

        <texture>flagging/video/dvd.png</texture>

        <visible>[substring(ListItem.FilenameAndPath,dvd) + ![substring(ListItem.FilenameAndPath,hddvd) | substring(ListItem.FilenameAndPath,bluray) | substring(ListItem.FilenameAndPath,bdrip)]] + !Skin.HasSetting(HideFilenameFlagging)</visible>

    </control>

    <control type="image">

        <description>TV Types Image</description>

        <width>80</width>

        <height>35</height>

        <aspectratio align="left">keep</aspectratio>

        <texture>flagging/video/TV.png</texture>

        <visible>[substring(ListItem.FilenameAndPath,pdtv) | substring(ListItem.FilenameAndPath,hdtv) | substring(ListItem.FilenameAndPath,dsr)] + !Skin.HasSetting(HideFilenameFlagging)</visible>

    </control>

    <control type="image">

        <description>VHS Image</description>

        <width>80</width>

        <height>35</height>

        <aspectratio align="left">keep</aspectratio>

        <texture>flagging/video/vhs.png</texture>

        <visible>substring(ListItem.FilenameAndPath,vhs) + !Skin.HasSetting(HideFilenameFlagging)</visible>

    </control>

</include>

With skin variables it could be:

Code:

<variable name="filename_video_type">

    <value condition="substring(ListItem.FilenameAndPath,bluray) | substring(ListItem.FilenameAndPath,bdrip)">bluray</value>

    <value condition="substring(ListItem.FilenameAndPath,hddvd)">hddvd</value>

    <value condition="substring(ListItem.FilenameAndPath,dvd)">dvd</value>

    <value condition="substring(ListItem.FilenameAndPath,pdtv) | substring(ListItem.FilenameAndPath,hdtv) | substring(ListItem.FilenameAndPath,dsr)">TV</value>

    <value condition="substring(ListItem.FilenameAndPath,vhs)">vhs</value>

</variable>

-- note difference with "dvd" checking: in variables condition I don't check against "hddvd" because if path would contain "hddvd" previous condition would be met and variable would already have value hddvd (and further checking would be aborted)

and then single image control with

Code:

<control type="image">

    <description>Video type image</description>

    <width>80</width>

    <height>35</height>

    <aspectratio align="left">keep</aspectratio>

    <texture>$VAR[filename_video_type,flagging/video/,.png]</texture>

    <!-- alternatively You could omit $VAR and use <texture>filename_video_type</texture> (along with slightly changed variable values) -->

    <visible>!Skin.HasSetting(HideFilenameFlagging)</visible>

</control>

Of course variables could contain $INFO[] or any ether element normal label / texture could have.

Skin variables could be contained in variables.xml

Code:

<variables>

  <variable name="x">

    <value="foo">bar</value>

    <value>default</value> <!-- if default not set then default value would be empty "" -->

  </variable>

</variables>

Do You have ideas how to make it better? Let's start discussion.

wyrm · 2011-08-15 04:08

pieh Wrote:It was often mentioned - now it's about time to get it done.

This is now just discussion - it's not done yet

Do You have ideas how to make it better? Let's start discussion.

pieh,

Hey I'm happy to kick this one off, I like what you have suggested but why limit this to <texture>? Could you also include <onclick> in this party? For example I currently use this in my home.xml

PHP Code:

<item>
                    <icon>icon-tv.png</icon>
                    <thumb>icon-tv-blur1.png</thumb>
                    <label>31027</label>
                    <include condition="!Skin.String(tv-libraryentry)">TVLibraryTitle</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[369])">TVLibraryTitle</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[20108])">TVLibraryRoot</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[20387])">TVLibraryRecentlyadded</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[135])">TVLibraryGenres</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[652])">TVLibraryYears</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[344])">TVLibraryActors</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[20388])">TVLibraryStudios</include>
                    <include condition="StringCompare(Skin.String(tv-libraryentry),$LOCALIZE[744])">TVLibraryFiles</include>
                    <include condition="Skin.HasSetting(updatetventry)">RestartSkinTV</include>
                    <visible>!Skin.HasSetting(home-tv)</visible>
                </item> 

and each one of the includes is just a <onclick> like this

PHP Code:

<!-- TVLibraryTitle Include -->
    <include name="TVLibraryTitle">
        <onclick>ActivateWindow(Videos,tvshowtitles,return)</onclick>
    </include> 

if you included <onclick> in the skin variable party I could rewrite this as

PHP Code:

<item>
                    <icon>icon-tv.png</icon>
                    <thumb>icon-tv-blur1.png</thumb>
                    <label>31027</label>
                    <onclick>$VAR[tv-libraryentry]</onclick>
                    <include condition="Skin.HasSetting(updatetventry)">RestartSkinTV</include>
                    <visible>!Skin.HasSetting(home-tv)</visible>
                </item> 

then I could set the skin variable to the contents of the <onclick> in my settings menu. The benefit would be that home.xml would run a Sh!t load quicker and be a lot more readable. Yes, my settings menu would become slower but who cares as the limiting factor there is the user interaction and besides this only happens rarely so not a major problem.

Wyrm (xTV-SAF)

**jmarshall** · 2011-08-15 08:19

It looks fine to me, though I'd be tempted to at least consider dropping $VAR in favour of just using <texture>filename_video_type</texture>. Do we need the ability to combine $VAR with prefix/postfix stuff? If we do, then it makes sense to leave it that way. If not they're more like constants.

As for where to place in the XML my first thought was that the variables would be global to the skin, but I guess there may be some niceness to be had from limiting scope? Am not really sure what you plan is on that, but it seems to me that global is probably all we really need.

Cheers,
Jonathan

wyrm · 2011-08-15 08:31

jmarshall Wrote:It looks fine to me, though I'd be tempted to at least consider dropping $VAR in favour of just using <texture>filename_video_type</texture>. Do we need the ability to combine $VAR with prefix/postfix stuff? If we do, then it makes sense to leave it that way. If not they're more like constants.

Jonathan,

Don't think that is such a good idea. How would you tell if it was a skin variable or (as in your example) if that was a file in the .xbt file called "filename_video_type". The $VAR makes it very clear that it is a variable and not an actual name of an image file.

Just my 2c worth.
Wyrm (xTV-SAF)

Hitcher · 2011-08-15 08:49

wyrm Wrote:pieh,

Hey I'm happy to kick this one off, I like what you have suggested but why limit this to <texture>? Could you also include <onclick> in this party?

Wyrm (xTV-SAF)

I think this covers that -

https://github.com/xbmc/xbmc/pull/352

wyrm · 2011-08-15 09:11

Hitcher Wrote:I think this covers that -

https://github.com/xbmc/xbmc/pull/352

Hitcher,

Thanks was not aware of this. Will go have a look see. Reply to Jonathan's message still applies. Think unless there is a really good reason should still be $VAR[foo].

Wyrm (xTV-SAF)

wyrm · 2011-08-15 09:47

Hitcher Wrote:I think this covers that -

https://github.com/xbmc/xbmc/pull/352

Hitcher,

Just checked it out. It's close (will do away with the multiple includes) but to my way of thinking <onclick>$VAR[foo]</onclick> where foo is an action for <onclick> to perform will do away with multiple stringcompares (very slow) to include the one action that the user wants the button to do.

That is unless I have completely misread what pull/352 does. Still looks better than what I currently have so will recode to this later tonight.

Wyrm (xTV-SAF)

BTW, is there a limit on the number of <onclick> lines I can have in a <item>. I always thought it was three. That alone would make <onclick>$VAR[foo]</onclick> a much better way of doing things

**pieh** · 2011-08-15 10:17

wyrm Wrote:pieh,

Hey I'm happy to kick this one off, I like what you have suggested but why limit this to <texture>? Could you also include <onclick> in this party? For example I currently use this in my home.xml

This will apply to anything that You can use $INFO tags in (so onclicks, onfocus, visible, texture, label, altlabel, etc, I just mentioned most used tags I think)

jmarshall Wrote:It looks fine to me, though I'd be tempted to at least consider dropping $VAR in favour of just using <texture>filename_video_type</texture>. Do we need the ability to combine $VAR with prefix/postfix stuff? If we do, then it makes sense to leave it that way. If not they're more like constants.

I think If skinner want to use just variable as texture then we can ommit $VAR, but I think there are situations when he will want to use it in middle of static text/other infolabel so propably both ways should be supported

jmarshall Wrote:As for where to place in the XML my first thought was that the variables would be global to the skin, but I guess there may be some niceness to be had from limiting scope? Am not really sure what you plan is on that, but it seems to me that global is probably all we really need.

so, introduce variables.xml?
I didn't think too much on this (my concern was that all vars would be evaluated each frame, but after look at infomanager it seems that they will be evaluated only if needed/used?).

wyrm Wrote:Just checked it out. It's close (will do away with the multiple includes) but to my way of thinking <onclick>$VAR[foo]</onclick> where foo is an action for <onclick> to perform will do away with multiple stringcompares (very slow) to include the one action that the user wants the button to do.

That is unless I have completely misread what pull/352 does. Still looks better than what I currently have so will recode to this later tonight.

If You want to have just single action based on condition then Skin Vars is the way to go.

PR/352 will iterate through entire list of actions and will execute all actions that condition is met

wyrm Wrote:BTW, is there a limit on the number of <onclick> lines I can have in a <item>. I always thought it was three. That alone would make <onclick>$VAR[foo]</onclick> a much better way of doing things

there's no hardcoded limit of <onclick>, you can have as many as You want

**pieh** · 2011-08-15 11:13

another thought regarding wyrm example: as Your conditions need to be evaluated just once (on window load) there might be optional flag to say that this variable don't need to be evaluated each frame (<variable name="x" evaluate_just_on_window_load="true">, ofcourse better naming here would be needed ;P) - this would save comparing const strings every frame

--edit perhaps just using <constant name="x"> would be proper here?
--edit2 scratch that <constant> - it's already used in different purpose

wyrm · 2011-08-16 03:50

pieh Wrote:another thought regarding wyrm example: as Your conditions need to be evaluated just once (on window load) there might be optional flag to say that this variable don't need to be evaluated each frame (<variable name="x" evaluate_just_on_window_load="true">, ofcourse better naming here would be needed ;P) - this would save comparing const strings every frame

pieh,

You got me on that one sport, had not even thought about that. First of all maybe <variable name="x" onload="true"> could be used. I was assuming that this would only apply on window load, so default would probably be onload="true", but if others want to jump in here on what they think should happen that would be good.

On previous post, great that you are thinking of applying this to more than just textures. Sound like it's going to be a LOT of work, so a virtual beer for that man.

Quote:--edit perhaps just using <constant name="x"> would be proper here?

Not sure what you mean here, does this relate to above thoughts on $VAR or are you suggesting that I use constants as provided to solve my issue with posted example code? As was pointed out by Hitcher and yourself, there is a better way to code my example currently available (althought $VAR would be even better way to code problem). My posted code was more an example of how $VAR could be used to improve things (and to throw some ideas out to the forum). Will take provided hints to improve my code.

Thanks,
Wyrm (xTV-SAF)

Hitcher Skilled Skinner Posts: 9,936 Joined: Aug 2007 Reputation: 67 Location: Eastleigh, UK	2011-08-15 08:49 Post: #5 wyrm Wrote:pieh, Hey I'm happy to kick this one off, I like what you have suggested but why limit this to <texture>? Could you also include <onclick> in this party? Wyrm (xTV-SAF) I think this covers that - https://github.com/xbmc/xbmc/pull/352
	find quote

wyrm Skilled Skinner Posts: 768 Joined: Nov 2007 Reputation: 5 Location: Perth, Australia (GMT +8)	2011-08-15 09:11 Post: #6 Hitcher Wrote:I think this covers that - https://github.com/xbmc/xbmc/pull/352 Hitcher, Thanks was not aware of this. Will go have a look see. Reply to Jonathan's message still applies. Think unless there is a really good reason should still be $VAR[foo]. Wyrm (xTV-SAF)
	find quote