script.js

function gradioApp(){
    return document.getElementsByTagName('gradio-app')[0].shadowRoot;
}

function get_uiCurrentTab() {
    return gradioApp().querySelector('.tabs button:not(.border-transparent)')
}

uiUpdateCallbacks = []
uiTabChangeCallbacks = []
let uiCurrentTab = null

function onUiUpdate(callback){
    uiUpdateCallbacks.push(callback)
}
function onUiTabChange(callback){
    uiTabChangeCallbacks.push(callback)
}

function runCallback(x){
    try {
        x()
    } catch (e) {
        (console.error || console.log).call(console, e.message, e);
    }
}
function executeCallbacks(queue) {
    queue.forEach(runCallback)
}

document.addEventListener("DOMContentLoaded", function() {
    var mutationObserver = new MutationObserver(function(m){
        executeCallbacks(uiUpdateCallbacks);
        const newTab = get_uiCurrentTab();
        if ( newTab && ( newTab !== uiCurrentTab ) ) {
            uiCurrentTab = newTab;
            executeCallbacks(uiTabChangeCallbacks);
        }
    });
    mutationObserver.observe( gradioApp(), { childList:true, subtree:true })
});

/**
 * checks that a UI element is not in another hidden element or tab content
 */
function uiElementIsVisible(el) {
    let isVisible = !el.closest('.\\!hidden');
    if ( ! isVisible ) {
        return false;
    }

    while( isVisible = el.closest('.tabitem')?.style.display !== 'none' ) {
        if ( ! isVisible ) {
            return false;
        } else if ( el.parentElement ) {
            el = el.parentElement
        } else {
            break;
        }
    }
    return isVisible;
}