Question

Here’s an exerpt from the ADT’s latest changelog:

Build performance improvements.

The big changes in Ant, besides supporting the new type of library projects, and the build improvements mentioned above (aapt and png crunch cache) is that the new Ant build finally properly supports dependency check before doing any actions. This means that, while some steps (aapt, dex) are still not incremental, they, at least, won’t run if they don’t need to. In r13 and before, aidl compilation, resources ID generation, dex’ing, packaging, etc.. would happen all the time even if no file changed.

However after having updated everything I don’t see any performance boost when compiling my projects with ant. Unmodified projects are still built from scratch every ant debug install.

Should I activate these optimizations somewhere? or am I not using the right ant command?

Answer 1

No activation is needed other than updating your build.xml with something like

android update project -p . --target 2

After updating you should see the lines in your build log

 [echo] Handling aidl files...
 [aidl] No AIDL files to compile.
 [echo] ----------
 [echo] Handling RenderScript files... 
 [renderscript] No RenderScript files to compile.
 [echo] ----------
 [echo] Handling Resources...
 [aapt] No changed resources. R.java and Manifest.java untouched.
 [echo] ----------
 [dex] No new compiled code. No need to convert bytecode to dalvik format.
 [crunch] Crunched 0 PNG files to update cache
 [aapt] No changed resources or assets.
 [apkbuilder] No changes. No need to create apk.

…etc…

If you see it, then you are using mentioned optimizations from latest sdk-tools.