run-android.md

ern run-android

Description

• Runs a MiniApp on an Android emulator or connected device

Syntax

ern run-android

Options

--baseComposite <compositePath>

• Git or File System path, to the custom Composite repository (refer to the custom Composite documentation for more information).

--descriptor, -d

• complete native application descriptor

--dev [true|false]

• Enable or disable React Native dev support

--extra/-e

• Optional extra configuration specific to local container and runner
• Override the Android build config during local container generation and runner project by passing androidConfig attributes
  • As a json string For example --extra '{"androidConfig": {"androidGradlePlugin": "3.2.1","buildToolsVersion": "28.0.3","compileSdkVersion": "28","gradleDistributionVersion": "4.6","minSdkVersion": "19","sourceCompatibility": "VERSION_1_8","supportLibraryVersion": "28.0.0","targetCompatibility": "VERSION_1_8","targetSdkVersion": "28"}}' Find more information on android configuration
  • As a file path For example --extra /home/user/my-container-config.json In that case, the configuration will be read from the file.
  • As a Cauldron file path For example --extra cauldron://config/container/my-container-config.json In that case, the configuration will be read from the file stored in Cauldron. For this way to work, the file must exist in Cauldron (you can add a file to the cauldron by using the [ern cauldron add file] command). Find more information on configuring via cauldron

Alternatively, it is also possible to provide this extra configuration in the package.json of the MiniApp, inside the ern object. For example:

"ern": {
  "androidConfig": {
    "minSdkVersion": "19",
    "compileSdkVersion": "28"
  }
}

• Optional hooks to run an arbitary script before or after js bundling is possible.
  • If a script is defined as a preBundle hook, it will be executed after the composite generation, prior to running metro bundler, from the directory containing the generated composite project.
    • As a json string --extra '{"containerGenerator": {"hooks": {"preBundle": "/workspace/ern/picking-miniapp/script/pre-script.sh"}}}'
    • As a file path --extra <path>/container-config.json
    • As a Cauldron file path --extra cauldron://config/config.json
  • If a script is defined as a postBundle hook, it will be executed just after metro bundler has been run, from the directory containing the bundle.
    • As a json string --extra '{"containerGenerator": {"hooks": {"postBundle": "/workspace/ern/picking-miniapp/script/post-script.sh"}}}'
    • As a file path --extra <path>/container-config.json
    • As a Cauldron file path --extra cauldron://config/config.json

Program to use to run the script should be indicated using shebang pattern in the script itself as first line.

--host

• Host or ip to launch the local packager on (default: localhost)

--launchFlags <string>

• Extra options passed to am start command when launching the application (correspond to the Launch Flags in Run/Debug Configurations of application in Android Studio, as can be seen on screenshot below)
• Make sure to use = on the command line to provide this option, and keep the string in quotes. For example --launchFlags="--es aKey aStringValue --ei anotherKey 1"

--mainMiniAppName

• Name of the MiniApp to launch when starting the Runner application
• If you are running the command from the MainApp directory, only specify name of the MiniApp (Not the path).

--miniapps/m

• One or more MiniApps to combine in the Runner Container

--port

• Port on which the local packager should listen on (default: 8081)

--usePreviousDevice/-u

• Use the previously selected device to avoid prompt

JavaScript engine

By default Electrode Native will run the MiniApp with a Container that uses JavaScriptCore engine. If you'd rather like to run the MiniApp with Hermes engine, you should add the following inside the ern object of the MiniApp package.json :

{
  "androidConfig": {
    "jsEngine": "hermes"
  }
}

Remarks

• You can launch the MiniApp located in the current working directory or on a connected Android device or running emulator if available. If a connected Android device is not available, the command prompts you to select an emulator to launch from the list of installed emulator images.
• The first time you run this command from within a MiniApp directory, it generates an Android directory containing the Android runner application project. If the Android folder already exists (it is not the first run of the ern run-android command for this MiniApp), the existing runner project is used.
• After the runner project is generated, you can safely make native code modifications to it, knowing that the next time the ern run-android command is issued, the project and your changes will remain.
• If you want to regenerate the runner project from scratch, remove the Android directory.
• The miniapp can be any Yarn package descriptor, including Git or other file system path schemes.
• The ern run-android command is the ern equivalent of the react-native run-android command.
• If you are running the command from the MainApp directory, only specify name of the MiniApp (Not the path) in the --mainMiniAppName option.