Cordova plugin development - adding aar

Question

I am new to the cordova plugin development stuff. I want to write a plugin which is able to open a new android activty and showing some advertisement.

So I followed a simple tutorial here. That works very well and as expected.

Next step is to include this Android Studio Gradle project to my plugin.

My first try: Adding the gradle project to a subfolder of my cordova plugin and adding the following line to the plugin.xml file:

<framework src="libs/Broper/build.gradle" custom="true" type="gradleReference" />

also I tried:

<framework src="libs/Broper/app/build.gradle" custom="true" type="gradleReference" />

doesn't work. So I can't import the classes of that android studio project to my plugin java files.

Then a better solution (I thought so) is to add an AAR instead. But there I don't even have a clue what to do to add that AAR in my cordova plugin.

So, the question is: How do I add an android studio project (or library) to my cordova plugin the right way?

Answer 1

Here's what I've done to use a gradle reference with a Cordova plugin, I think this might help you.

Global structure :

pluginFolder/
  build-extras.gradle
  plugin.xml
  yourDirContainingYourAAR/
  src/
    android/
      yourFile.gradle
      myPlugin.java

Put your library, say foo.aar, in the yourDirContainingYourAAR directory (create it if needed)

• In the plugin.xml file :

  <platform name="android">
      <!-- your configuration elements, references, source files, etc... -->
  
      <framework src="src/android/yourFile.gradle" custom="true" type="gradleReference" />
  
      <resource-file src="yourDirContainingYourAAR/foo.aar" target="libs/foo.aar" />
  </platform>
  

• In the gradle file yourFile.gradle :

  repositories{    
    jcenter()
    flatDir {
        dirs 'libs'
     }
  }
  
  dependencies {
     compile(name:'foo', ext:'aar')
  }
  
  android {
    packagingOptions {
      exclude 'META-INF/NOTICE'
      exclude 'META-INF/LICENSE'
    }
  }
  

• In the root folder of your plugin (same level as plugin.xml ) create a build-extras.gradle. If needed, add or remove minSdkVersion and targetSdkVersion according to your project needs :

  android {
      defaultConfig {
          minSdkVersion 16
          targetSdkVersion 22
      }
  
     packagingOptions {
         exclude 'META-INF/NOTICE'
         exclude 'META-INF/LICENSE'
     }
  }
  

Answer 2

There has to be a slight modification to Niko's answer

When gradle runs the compilation using Niko's answer, it searches for the libs in app/libs which is not present in the project (it does in the standard Android Studio project, but in Cordova Android project structure the libs folder is different). However the plugin copies the aar library to app/src/main/libs which can make us think it is copying the aar to app/libs

<resource-file src="yourDirContainingYourAAR/foo.aar" target="libs/foo.aar" />

Hence the gradle file should be

repositories{    
 jcenter()
   flatDir {
     dirs 'src/main/libs'
   }
}

dependencies {
  compile(name:'foo', ext:'aar')
}

android {
 packagingOptions {
  exclude 'META-INF/NOTICE'
  exclude 'META-INF/LICENSE'
 }
}

This will give you a successful compilation of the app

Cheers!!

Answer 3

If all the above fails just like it did to me... Try these alteration:

1. Use lib-file instead of resource-file

<lib-file src="yourDirContainingYourAAR/foo.aar"/>

2. Use implementation instead of compile

dependencies {
    implementation fileTree(include: ['*.aar'], dir: 'libs')
}

Ref: https://forum.ionicframework.com/t/add-aar-file-to-cordova-plugin/168675/3

Answer 4

Okay, because there are multiple answers here and none of them fully capture everything that needs to be done, I'm going to create an all inclusive answer. Hopefully it will save people some time and frustration.

It's pretty straight forward, you just have to update plugin.xml to state where the .aar file should go inside the android project. Then you have to tell gradle where to look for it.

So I have this directory structure (you can use a different one):

-- my-plugin/
   |-- deps/
       |-- some-dependency.aar
   |-- src/
       |-- MyPlugin.java
   |-- www/
       |-- plugin.js
   |-- package.json
   |-- plugin-settings.gradle
   |-- plugin.xml

Step 1

The first step is to tell cordova where to put the .aar file. You do that by including a line in plugin.xml:

<resource-file src="deps/some-dependency.aar" target="libs/some-dependency.aar" />

That will grab the file from the deps folder in your source and stick it into the the platforms/android/app/src/main/libs/ folder in the resulting android project. Apparently the target path is relative to the platforms/android/app/src/main folder. Not sure if that can be changed.

Before moving on to step 2, it might be a good idea to run cordova build android to verify that the .aar file is being copied to the right place.

Step 2

So once that's working the next step is to tell gradle where the file is so it can resolve it correctly during the build. You do that by creating your own .gradle file that will be merged with the main gradle file that cordova creates for you.

Create a file called plugin-settings.gradle and put the following line in it:

repositories{    
  flatDir {
      dirs 'src/main/libs'
   }
}

dependencies {
   compile(name:'some-dependency', ext:'aar')
}

Note that the line dirs 'src/main/libs' tells gradle where to look for the .aar file. It does not dictate where cordova puts that file, just where gradle looks for it. Also note that the path is relative to the platforms/android/app/ folder and that the resulting path must match where cordova is putting the .aar file.

So in my plugin.xml file I have target="libs/some-dependency.aar" therefore in my plugin-settings.gradle file I have dirs 'src/main/libs'. If these don't line up you're going to get build errors.

Step 3

Now tell your plugin to use the .gradle file:

<framework src="plugin-settings.gradle" custom="true" type="gradleReference" />

Note that you can put the pllugin-settings.gradle file where ever you want and you can call it whatever you want. Just make sure the <framework> entry matches.

Yay

That's pretty much it. You should be able to build and run your app at this point. You're welcome.