解决CocosCreator打包Android时的“ no rule to make target `cocos2djs` ” 问题

感谢YF Lu同学的耐心测试以及详细整理！这里分享并记录一下问题的解决方案和一些原因

CocosCreator Android building troublesh…

Android env setup and building panel

First make sure that you have working “Android SDK+NDK” combination setup in the “overall CocosCreator Settings”.
Second, mind some settings in the build panel.

When building for “Android”,** shall I use “default” or “link” template?** Actually either works, but you should tailor-make the “build-template folder” for the chosen template.

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Gradle version

Use a matching Gradle version

Make sure that you use “Matching CocosCreator version & Gradle version”, e.g. “CocosCreator or v2.1.3 only works with Gradle-4.x”. Note that “AndroidStudio” could use a different Gradle version than that specified by “GradleWrapper”, to be sure about the pipeline you can always build with your “GradleWrapper”.

What if you didn’t use a matching Gradle version

If due to an unknown reason your built Android project just comes up with an unmatching Gradle version, you might get a "no rule to make target cocos2djs" error.

Such problem could occur after blind clicked “upgrade” in AndroidStudio, which may overwrite your “project.android-studio/build.grade”.

Another case showed that the same error might also show up after a newly created “HelloWorld” project (from CocosCreator v2.1.3 welcome pane, no build-template customization, no CocosCreator folder src code customization, even without opening AndroidStudio). In this case the resulted “proj.android-studio/build.gradle” uses a “com.android.tools.build:gradle:4.x.x (the AndroidGradlePlugin)”, and the automatically chosen “GradleWrapper version” will be “5.x” (the actual Gradle).

There were some build warning like “deprecared variant.mergeAssets”, not sure whether it’s relevant to this issue.

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Solution

You cannot just change the “distributionurl” in “proj.android-studio/gradle/wrapper/gradle-wrapper.properties” to use “another Gradle version”, which will only result in yet some other building issues.

The currently working solution is to create a “Gradle version constraint build-template
file”, as shown in the screenshot below, to specify version constraints.

Building from CLI

To see explicit warnings of the use of “obsolete APIs”.

bashshell> /path/to/frontend/build/jsb-link/frameworks/runtime- src/proj.android-studio (master)
$ ./gradlew build -Pandroid.debug.obsoleteApi=true --warning-mode all