Browser API and Procs

Browser Lifecycle and Error Events

Client-side browser events are subscribed with mp.events.add(...).

browserCreated

Fired when a browser instance is created.

Arguments: (browser)

Note: this confirms instantiation only; the page may still be loading.

browserDomReady

Fired when the iframe page is loaded and bridge handshake is confirmed.

Arguments: (browser)

Use this event as the safe point to call browser.call(...).

browserLoadError

Fired when the page fails to load or does not signal ready within 5 seconds.

Arguments: (browser, info)

info fields:

• url: attempted page URL
• message: error description

Common causes: wrong URL, or a cross-origin page without _bridge.js.

browserError

Fired when a browser page throws an error.

Bridge captures errors from window.onerror, unhandledrejection, UI event handlers, executeCached, and resource loading, then forwards them to client.

Arguments: (browser, info)

browser is the BrowserMp instance (or null if no longer available).

info fields:

• kind: "error" | "unhandledrejection" | "handler" | "exec" | "resource"
• message: error text
• stack: stack trace (if available)
• source: script source URL (for script errors)
• lineno: line number (for script errors)
• colno: column number (for script errors)
• event: UI event name that failed (only for kind: "handler")
• browserId: browser id

Example

const browser = mp.browsers.new("@resource-name/ui/index.html");

mp.events.add("browserCreated", (browser) => {
  mp.console.logInfo(`Browser created: ${browser?.id ?? "unknown"}`);
});

mp.events.add("browserError", (browser, info) => {
  mp.console.logError(`[UI ${info.kind}] ${info.message}`);
  if (info.stack) mp.console.logError(info.stack);
});

mp.events.add("browserDomReady", (browser) => {
  browser.call("app:init", { user: "Adrian" });
});

mp.events.add("browserLoadError", (browser, info) => {
  mp.console.logError(`UI failed to load: ${info.url} - ${info.message}`);
});

In Browser Page

mp.events.add("setData", (state) => {
  console.log(state);
});

mp.events.addProc("collectForm", () => {
  return { ok: true };
});

mp.trigger("ui:clicked", "save");

Proc Timeouts

Browser proc calls use timeout-based pending maps on both client and CEF sides.

Use the browser manager APIs to read or change the timeout:

• mp.browsers.setProcTimeout(ms): sets the global proc timeout in milliseconds.
• mp.browsers.procTimeout: gets the current global proc timeout in milliseconds.

// Set proc timeout to 15 seconds.
mp.browsers.setProcTimeout(15000);

// Read current timeout value.
const currentTimeout = mp.browsers.procTimeout;
mp.console.logInfo(`Proc timeout: ${currentTimeout}ms`);

Design handlers to return quickly or route long work through your server event/proc flow.

Chat Browser Integration

A browser can be marked as chat with markAsChat(), letting mp.gui.chat mirror messages into that UI.