Angular property binding重复触发的问题讨论

第三次触发

class ApplicationRef {
    /**
     * \@internal
     * @param {?} _zone
     * @param {?} _console
     * @param {?} _injector
     * @param {?} _exceptionHandler
     * @param {?} _componentFactoryResolver
     * @param {?} _initStatus
     */
    constructor(_zone, _console, _injector, _exceptionHandler, _componentFactoryResolver, _initStatus) {
        this._zone = _zone;
        this._console = _console;
        this._injector = _injector;
        this._exceptionHandler = _exceptionHandler;
        this._componentFactoryResolver = _componentFactoryResolver;
        this._initStatus = _initStatus;
        /**
         * \@internal
         */
        this._bootstrapListeners = [];
        this._views = [];
        this._runningTick = false;
        this._enforceNoNewChanges = false;
        this._stable = true;
        /**
         * Get a list of component types registered to this application.
         * This list is populated even before the component is created.
         */
        this.componentTypes = [];
        /**
         * Get a list of components registered to this application.
         */
        this.components = [];
        this._enforceNoNewChanges = isDevMode();
        this._zone.onMicrotaskEmpty.subscribe({
            next: (/**
             * @return {?}
             */
            () => {
                this._zone.run((/**
                 * @return {?}
                 */
                () => {
                    this.tick();
                }));
            })
        });