With Starling Builder extension, you are able to add custom components and theme without recompiling the editor.

The extension repository is located at https://github.com/yuhengh/starling-builder-extensions

For the time being (v2.5), the editor supports the following 2 extensions:

• EmbeddedComponents.swf
• EmbeddedTheme.swf

• Download and install AIR SDK 19+ and IntelliJ IDEA Ultimate Edition
• Checkout the repository using

  git clone https://github.com/yuhengh/starling-builder-extensions --recursive

• Open IntelliJ, click on File → Open and select starling-builder-extensions directory
• Click on File → Project Structure → SDKs, then create a FLEX/AIR SDK called AIRSDK
• Click on Run → Edit Configurations, create a Flash App Run/Debug Configuration and select the test build config
• Run the Run/Debug configuration just created

• Download and install AIR SDK 19+ and Flash Builder 4.7
• Checkout the repository using

  git clone https://github.com/yuhengh/starling-builder-extensions --recursive

• Click on File → New → ActionScript Library Project, select starling-builder-extensions directory
• Set the ActionScript Build Path as below

• Right click tests/src/starlingbuilder/demo/Main.as → Set as Default App
• Run the project

• Download and install AIR SDK 19+ and FlashDevelop
• Checkout the repository using

  git clone https://github.com/yuhengh/starling-builder-extensions --recursive

• Open FlashDevelop, Goto Project → New Project → AIR AS3 Projector, select starling-builder-extensions folder
• Set the ActionScript Build Path as below (Right click folder in project tab and choose “Add Source Path” to set source path, right click folder in project tab and choose “Add To Library” to set library path)

• Right click tests/src/starlingbuilder/demo/Main.as and select “Set Document Class”
• Copy src/starlingbuilder/editor/Main-app.xml to the root folder, rename to application.xml to replace the generated one.
• In application.xml, change the xmlns to match your AIRSDK version
• Goto Project → Properties, set the output file to “bin\Main.swf” (this has to match the swf file name inside application.xml
• Run the project

• Download and install AIR SDK 19+ and IntelliJ IDEA Ultimate Edition
• Checkout the repository using

  git clone https://github.com/yuhengh/starling-builder-extensions --recursive

• Open IntelliJ, click on File → Open to open the project, select starling-builder-extensions directory
• Click on Build → Rebuild Project, then copy the built swf files to YOUR_WORKSPACE/libs directory
• If you have modified or added any custom components，click on Workspace → Delete template override to make sure the template is up to date
• Restart Starling Builder

• Download and install AIR SDK 19+ and Apache Ant
• Checkout the repository using

  git clone https://github.com/yuhengh/starling-builder-extensions --recursive

• Open starling-builder-extensions/buildscript/build.properties, change airsdk.root to point to your AIR sdk folder
• Open terminal, cd starling-builder-extensions/buildscript and type ant to start building
• Copy the built swf files to YOUR_WORKSPACE/libs directory
• If you have modified or added any custom components，click on Workspace → Delete template override to make sure the template is up to date
• Restart Starling Builder

If you want to create your own custom UI components, you can compile them into this extension

The default EmbeddedComponents.swf is located at https://github.com/yuhengh/starling-builder-extensions/blob/2.0/deliverable/EmbeddedComponents.swf

For more information please checkout Custom UI components

If you want to create your own feathers theme, you can compile it into this extension

The default EmbeddedTheme.swf is located at https://github.com/yuhengh/starling-builder-extensions/blob/2.0/deliverable/EmbeddedTheme.swf

For more information please checkout Custom feathers theme