pages

Pages

orca.pages lets a plugin add its own tab to the main window, next to OrcaSlicer's built-in tabs (Prepare, Preview, Device, ...). The tab hosts an HTML page supplied by the plugin. Subclass orca.pages.PagesPluginCapabilityBase; its get_type() returns Pages.

Method	Required	Purpose
get_name()	yes	the tab label
get_ui()	yes	return the page's HTML as a string
get_icon()	no	return the path of an .svg / .png tab icon; empty (the default) for none
on_message(data)	no	receives each orca.postMessage(obj) from the page, decoded from JSON
post_message(data)	provided	send a JSON-compatible value to the page's orca.onMessage handlers

import orca

PAGE = """
<h2>Stats</h2><pre id="out">waiting...</pre>
<script>
  orca.onMessage(d => document.getElementById('out').textContent = JSON.stringify(d, null, 2));
  orca.postMessage({type: 'ready'});
</script>
"""

class StatsPage(orca.pages.PagesPluginCapabilityBase):
    def get_name(self): return "Stats"
    def get_ui(self): return PAGE

    def on_message(self, data):
        if data.get("type") == "ready":
            self.post_message({"objects": len(orca.host.model().objects())})

@orca.plugin
class StatsPlugin(orca.base):
    def register_capabilities(self):
        orca.register_capability(StatsPage)

Behavior

• A tab is added when the capability is loaded and enabled, and removed when it is disabled or its plugin is unloaded. The page itself is built the first time the tab is shown, so get_ui() is not called until then.
• The page gets a window.orca bridge with orca.postMessage(obj) and orca.onMessage(cb) (there is no submit() or close()). It is themed like the Host UI dialogs, and if the user reloads it the plugin's HTML is loaded again, so keep the authoritative state in the plugin and have the page ask for it on load.
• post_message() before the page has been built is dropped; the pattern above (the page asks for its data when it loads) avoids that.
• A link that would open a new window is loaded in the page itself.
• If get_ui() raises, the error is logged and the tab stays empty.
• The number of plugin tabs shown side by side is set in Preferences > General > Plugins > Visible plugin pages (1-10, default 5). Further pages collapse into a dropdown on the last plugin tab.

See Registry for registration and the members every capability inherits.