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androidxmlstringcode-injection

Android: How to inject a <string> element into another <string> element in XML?


I would like to know whether there is a way to insert/inject a <string> element defined in an XML file into another <string> element, doing that just with XML.

For example I could have:

<string name="author">Francesco</string>`

and I am looking for something like:

<string name="about_application">Author: @string/author</string>`

so that getString(R.string.about_application) would result in "Author: Francesco".

I know that I could combine the two elements in Java code using String.format(string, formatArgs)like for example:

<string name="author">Francesco</string>
<string name="about_application">Author: %1$s</string>`

and then in code use

String.format(getString(R.string.about_application), getString(R.string.author))

but I would like to do it in XML directly.

Can anyone suggest me a way to do it?


Solution

  • If I understand what you are looking to do, then internal (parsed) general entities might help you achieve what you are looking for.

    An example of how you can define the value "Francesco" as an entity called "auth" and then use it in your XML:

    <?xml version="1.0"?>
    <!DOCTYPE doc [
      <!ENTITY auth "Francesco">
    ]>
    <doc>
      <string name="author">&auth;</string>
      <string name="about_application">Author: &auth;</string>
    </doc>
    

    When read by an XML parser, the document will be parsed and evaluated, or "seen", as:

    <?xml version="1.0"?>
    <doc>
      <string name="author">Francesco</string>
      <string name="about_application">Author: Francesco</string>
    </doc>