Multidex Configuration Guide

Buck does support multidex, OkBuck support it since 0.4.7.

There are 3 steps to enable it:

1 . enable multidex in your app/build.gradle:

android {
    ...

    defaultConfig {
        ...
        multiDexEnabled true
        ...
    }
}

dependencies {
    compile 'com.android.support:multidex:1.0.1'
    ...
}

2 . set OkBuck multidex related configuration in your root build.gradle:

NOTE TAHT below are example, do not copy these into your configuration! See more at below.

okbuck {
    ...
    linearAllocHardLimit = [
            app: 7194304
    ]
    primaryDexPatterns = [
            app: [
                    '^com/github/piasy/okbuck/example/AppShell^',
                    '^com/github/piasy/okbuck/example/BuildConfig^',
                    '^android/support/multidex/',
                    '^com/facebook/buck/android/support/exopackage/',
                    '^com/github/promeg/xlog_android/lib/XLogConfig^',
                    '^com/squareup/leakcanary/LeakCanary^',
            ]
    ]
    ...
}

3 . linearAllocHardLimit and primaryDexPatterns values should be determined by experiment.

这俩参数目前需要通过实验确定。

The start value could be 65535 and your Application class full classpath, then run your buck install command, (e.g. buck install -r app).

If buck failed with error like:

DexWithClasses buck-out/gen/.okbuck/app/aar__design-23.1.1.aar#aar_prebuilt_jar,
dex.dex.jar with cost 514808 exceeds the max cost 65535 for a secondary dex file.

then you should set linearAllocHardLimit an int value greater than 514808 (the number given by buck), usually you can set a big value like 10000000.

linearAllocHardLimit 可以首先设置一个很大的数字，例如10000000。使用OkBuck生成BUCK配置之后，执行buck的install/build命令，如果看到上述提示，就把这个参数改得大于提示的数字即可。

Then run your app, if it crashes with error like:

java.lang.RuntimeException: Unable to instantiate application com.github.piasy.okbuck.example.MyApp:
 java.lang.ClassNotFoundException: Didn't find class "com.github.piasy.okbuck.example.MyApp" on path: 
DexPathList[[zip file "/data/app/com.github.piasy.okbuck.example-2.apk"],nativeLibraryDirectories=[/data/app-lib/com.github.piasy.okbuck.example-2, /vendor/lib, /system/lib]]

Then you should add the missing class path into the primaryDexPatterns list, in format of:

primaryDexPatterns可以先是一个空的数组，如果没有遇到上面的数字错误，或者已经解决了数字错误，安装APP之后运行，如果有上述找不到类的错误，就把相应的类加入到这个参数数组中，对应规则如下：

com.github.piasy.okbuck.example.MyApp ==> ^com/github/piasy/okbuck/example/MyApp^