AppML - Messages

Use AppML messages to react to lifecycle events and customize presentation behavior.

How it works

The AppML client can communicate with a controller through message information on its application object. A handler can perform focused tasks such as formatting displayed values, validation feedback, or error handling. Keep controller logic small and avoid unsafe insertion of untrusted HTML.

Good practice

• Use matching versions of the AppML client, model format, and examples.
• Keep secrets and permission checks out of browser-delivered HTML, JavaScript, and model files.
• Validate input and authorize every read or write on the server.
• Handle loading, empty, and error states, and check generated content for accessibility.

Further reading: Tutorialspoint: AppML - Messages · AppML library reference.

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