activator

packages/web/src/utility/createActivator.ts

@@ -0,0 +1,52 @@
+import { getContext } from 'svelte';
+import { get_current_component, onMount, setContext } from 'svelte/internal';
+import invalidateCommands from '../commands/invalidateCommands';
+
+const lastActiveDictionary = {};
+
+export default function createActivator(name, activateOnTabVisible) {
+  const instance = get_current_component();
+  const tabVisible: any = getContext('tabVisible');
+  const tabid = getContext('tabid');
+  const parentActivatorInstance = getContext('parentActivatorInstance') as any;
+  setContext('parentActivatorInstance', instance);
+  let tabVisibleValue;
+
+  onMount(() => {
+    const unsubscribeTabVisible = tabVisible.subscribe(value => {
+      tabVisibleValue = value;
+      if (activateOnTabVisible) {
+        activate();
+      }
+    });
+    invalidateCommands();
+
+    return () => {
+      unsubscribeTabVisible();
+    };
+  });
+
+  const activate = () => {
+    lastActiveDictionary[name] = instance;
+    if (parentActivatorInstance) {
+      parentActivatorInstance.activator.activate();
+    }
+  };
+
+  const getTabVisible = () => tabVisibleValue;
+
+  return {
+    activate,
+    tabid,
+    getTabVisible,
+  };
+}
+
+export function getActiveComponent(name) {
+  const current = lastActiveDictionary[name];
+  if (!current) return null;
+  if (!current.activator) return null;
+  if (!current.activator.getTabVisible) return null;
+  if (!current.activator.getTabVisible()) return null;
+  return current;
+}