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androidoverlayandroid-source

How does the Android source overlays work?

In the android source in the device/sample folder there is a folder called overlays. You see the same overlay folder in e.g. the cyanogen mods.

What is this overlay folder? How does it work? What is it used for? Where can I read more about it?

Thanks in advance

Solution

  • For instance, imagine that you want to modify some files in Android source for your device (for instance, you want to add additional string to Launcher resources). It is not recommended to modify the actual sources of Android.

    Instead of this you create overlay that mimics the actual filesystem path layout of Android and put there your changed file. In case of string in Laucher, you create directories that corresponds to the path: packages/apps/Launcher2/res/values and put there modified strings.xml

    Thus, when you build your device this file will be substituted.