I know it seems confusing, but the <preference> tag inside the <config-file> tag is just some xml insertion into the config.xml file that is specified, but is not related to the <preference> tag specified for plugin.xml. It is the <preference> tag for config.xml.
It should behave as specified in the Plugin Spec [1], when inside <platform> tags, except for what I explained above. Answering your points: 1) Yes, it ignores the value attribute, only 'name' is applicable per the spec. 2) They shouldn't be ignored if inside the <platform> node, seems to be a bug (unless the tool is smart enough to know if the variable is actually being used and not prompt -- but that seems to be bad design) [1] http://cordova.apache.org/docs/en/4.0.0/plugin_ref_spec.md.html#Plugin%20Specification On Fri, Nov 7, 2014 at 7:18 AM, Horn, Julian C <julian.c.h...@intel.com> wrote: > Leo's question really hasn't been answered yet. Let me try to make this > more concrete and see if anyone can explain whether the current behavior of > the CLI is correct or not. > > The plugin.xml in the StatusBar plugin contains the following content: > > ... > <platform name="ios"> > <config-file target="config.xml" parent="/*">. > ... > <preference name="StatusBarOverlaysWebView" value="true" /> > > There are several mysteries here. > > 1) What does it mean if the name attribute of a preference tag does not > obey the "only capital letters, digits, or underscores" rule? Apparently > it can never cause variable replacement. > 2) What does the value attribute mean? Does this supply a default value > for a variable if the variable is not mentioned in the --variable flag > (thus making the variable "optional")? > 3) Where can <preference> tags legally appear? Must they be outside of > <platform> tags, or can they be inside <platform> tags or even inside > <config-file> tags? > > Our experiments with CLI 4.0.1-dev show the following: > > 1) The value attribute is ignored by the CLI, or at least it doesn't > create a default value. > > For example, suppose you put the following preference tag outside of any > <platform> tag. > <preference name="API_KEY" value="my-api-key" /> > We found that the user is still required to supply --variable API_KEY, > which means that "my-api-key" never becomes the value of API_KEY. > > 2) <preference> tags appear to be ignored by the CLI if they appear below > a <platform> node. > > If you move the <preference> node shown above from outside a <platform> > node to inside a <platform> node, then the CLI stops prompting for a > --variable flag and $API_KEY is not replaced by anything. > > It looks to us like the <preference> tag is overloaded. When it appears > outside the <platform> tag it defines a variable. When it appears inside a > <platform> tag it does not. The meaning of the <preference> tag within a > <platform> tag is apparently determined by the platform. > > If people agree that this is correct then the documentation can be updated > accordingly. However, we did see some code in the implementation that > seemed to be looking for <preference> tags inside of <platform> tags. It > seems like this isn't working as intended, but then again we can't figure > out what the intention is. > > Julian > > -----Original Message----- > From: Marcel Kinard [mailto:cmarc...@gmail.com] > Sent: Friday, November 07, 2014 9:42 AM > To: dev@cordova.apache.org > Subject: Re: Questions re: plugin variables > > If there is a reasonable question from a user, it should probably be added > to the docs (assuming it's not already there). > > Leo, would you like to do a pull request? > > On Nov 5, 2014, at 8:24 PM, Mark Koudritsky <kam...@google.com> wrote: > > > Variables should to be provided when adding the plugin > > E.g: > > > > cordova plugin add org.some.plugin --variable API_KEY=some_value > > > > Example of a plugin that uses variables: > > http://plugins.cordova.io/#/package/com.phonegap.plugins.facebookconne > > ct > > > > Relevant places in the code in cordova-lib: > > Where variables are checked during plugin add: > > > > https://github.com/apache/cordova-lib/blob/master/cordova-lib/src/cord > > ova/plugin.js#L126 > > > > https://github.com/apache/cordova-lib/blob/master/cordova-lib/src/plug > > man/install.js#L296 > > > > Here each variable is replaced with its value when generating the > > "config munge" which is an object that describes changes that need to > > be applied to the platform dir. > > > > https://github.com/apache/cordova-lib/blob/master/cordova-lib/src/plug > > man/util/config-changes.js#L368 > > > > > > On Wed, Nov 5, 2014 at 5:28 PM, Treggiari, Leo > > <leo.treggi...@intel.com> > > wrote: > > > >> I'm having a hard time understanding exactly how plugin variables work. > >> It's probably a level of detail that only plugin developers and tool > >> developers need to be concerned about. I'd appreciate it if someone > >> can give me the answers. > >> > >> 1. "variables can be indicated by a dollar-sign followed by a series > >> of capital letters, digits, or underscores." > >> "To make the variable mandatory, the <platform> tag needs to > >> contain a <preference> tag." > >> Does this mean that there are optional and required variables - i.e? > >> - A variable reference is defined by a lexical element which > >> begins with a $ and is followed only by capital letters, digits, or > underscores? > >> - A variable is made mandatory by the presence of a > >> <preference> tag which uses the same name with the $ removed? > >> - Can this <preference> tag be anywhere in the plugin.xml file, > >> or must it be the direct child of the <plugin> element or > >> a <platform> element? > >> - Can the variable references be anywhere or only within strings? > >> > >> 2. Where and when are the variables replaced by their value? > >> - plugin.xml is the only place that the variable value is used > >> and only for replacing the variable references? > >> - When in Cordova CLI do the values get applied - during "add", > >> during "prepare"? > >> > >> 3. What happens if you combine dependencies with variables. For > >> example, suppose A depends on B, and B requires a variable X. How do > >> you supply the value? > >> > >> Thanks, > >> Leo > >> > >> > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@cordova.apache.org > For additional commands, e-mail: dev-h...@cordova.apache.org > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@cordova.apache.org > For additional commands, e-mail: dev-h...@cordova.apache.org > >
