AAML: The Simplest Markup Language for Android

You may think this is nonsense, but I do not like an IDE. Usually I do all the work in the vim + tmux + terminal. I recognize all the advantages of IDE, it’s just more convenient for me in a good text editor. But it's not about that.

When I write something for android - I often correct XML (markup, styles, strings, ...). So in a text editor to do it is not very convenient. And I decided to spend a couple of hours and write an XML generator based on a simplified markup language (like lesscss or stylus for CSS). Still, NIH is a very tempting incentive.

AAML (another android markup language) has turned out with a very simple syntax. Items begin with a colon. Commas (or line breaks) separate attributes. Tabs (or spaces, or both) define the nesting of elements. Comments begin with a grid. Some simple layout looks like this:
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# Main layout :LinearLayout layout fill, padding 0dp 16dp, orientation vertical :EditText layout fill wrap hint @string/to :EditText layout fill wrap hint @string/subject :EditText layout fill 0dp 1 gravity top hint @string/message :Button#btn_send layout 100dp wrap gravity right text @string/send 

This AAML markup is compiled into:

 <?xml version="1.0" encoding="utf-8"?> <!-- Main layout --> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:paddingTop="0dp" android:paddingRight="16dp" android:paddingBottom="0dp" android:paddingLeft="16dp" android:orientation="vertical"> <EditText android:layout_width="fill_parent" android:layout_height="match_parent" android:hint="@string/to" /> <EditText android:layout_width="fill_parent" android:layout_height="match_parent" android:hint="@string/subject" /> <EditText android:layout_width="fill_parent" android:layout_height="0dp" android:layout_weight="1" android:gravity="top" android:hint="@string/message" /> <Button android:id="@+id/btn_send" android:layout_width="100dp" android:layout_height="match_parent" android:gravity="right" android:text="@string/send" /> </LinearLayout> 

More on the DRY principle there is support for macros and aliases. Aliases allow you to specify a new name for something — an attribute (to write “wrap” instead of “wrap_content”), a value (to determine the color or size of the font once and use the alias as the name of a variable), etc.

Macros accept a series of arguments. Arguments names really can not be given (and the macros are assumed only the most simple). Instead, positional arguments are used, as in Bash ($ 1, $ 2, $ 3, etc.). Here are the macros and aliases used in the example above:

 #  :def wrap wrap_content :def fill match_parent :def match match_parent #  :def layout:3 layout_widht $1, layout_height $2, layout_weight $3 :def layout:2 layout_widht $1, layout_height $2 :def layout:1 layout $1 $1 :def padding:4 paddingTop $1, paddingRight $2, paddingBottom $3, paddingLeft $4 :def padding:2 padding $1 $2 $1 $2 :def padding:1 padding $1 $1 

Probably, such macros should be made standard for different types of XML (for layout - some, for strings - others, etc.)

Written by AAML in python. It has no dependencies, the code contains only 200 lines. It works in two modes - it converts the * .aaml file to * .xml or recursively processes all files from one folder and puts the resulting xml into another. This is convenient if you create aaml / layout, aaml / values, aaml / xml and add the results to res / layout, etc.

To automate this process, you can create custom_rules.xml:

 <?xml version="1.0" encoding="UTF-8"?> <project> <target name="-pre-build"> <exec executable="aaml"> <arg value="aaml"/> <arg value="res"/> </exec> </target> </project> 

Now aaml will be converted to xml with each build of the project automatically.

Sources are on bitbucket: bitbucket.org/zserge/aaml
License - MIT.

At the end of the post I have a question for the habrovans - is it worth developing this project? Are there any more freaks who write XML manually? If so, then any suggestions, feature requests, comments, bugs, criticism are welcome.