Allow registration of listeners during browser creation (config.listeners)

Author: jrobinso

dev/ucsc/hub.html

@@ -46,14 +46,19 @@
     const hub = await Hub.loadHub("https://hgdownload.soe.ucsc.edu/hubs/GCA/009/914/755/GCA_009914755.4/hub.txt", hubOptions)
 
     const igvConfig = {
-        reference: hub.getGenomeConfig()
+        reference: hub.getGenomeConfig(),
+        listeners: {
+            'genomechange': ({genome, trackConfigurations}) => {
+                console.log('genomechange')
+                console.log(genome)
+                console.log(trackConfigurations)
+            }
+        }
     }
 
+
     const browser = await igv.createBrowser(document.getElementById('igvDiv'), igvConfig)
 
-    browser.on('genomechange', (args) => {
-        console.log(args)
-    })
 
     const selector = document.getElementById("select")
     selector.addEventListener("change", () => document.getElementById("hub-input").value = selector.value)

js/browser.js

@@ -115,6 +115,12 @@ class Browser {
         // Map of event name -> [ handlerFn, ... ]
         this.eventHandlers = {}
 
+        if(config.listeners) {
+            for(let evt of Object.keys(config.listeners)) {
+                this.on(evt, config.listeners[evt])
+            }
+        }
+
         this.on('trackremoved', () => {
 
             const found = this.findTracks(track => typeof track.getSamples === 'function')

js/igv-create.js

@@ -69,7 +69,6 @@ async function createBrowser(parentDiv, config) {
     const browser = new Browser(config, parentDiv)
     allBrowsers.push(browser)
 
-
     // Lod initial sessio
     browser.startSpinner()