Description
// 实现 store.subscribe
subscribe (subscriber, actionSubscriber) {
const emitter = this.$emitter;
const originViewInstance = getCurrentPages().pop() || {};
if (subscriber) {
this.storeUpdateLisitenerDispose = emitter.addListener('updateState', ({ state, mutation, prevState }) => {
const currentPageInstance = getCurrentPages().pop() || {};
const instanceView = originViewInstance.$viewId || -1;
const currentView = currentPageInstance.$viewId || -1;
// 已经不在当前页面的不再触发
if (instanceView === currentView) {
subscriber(mutation, wrapState({ ...this.storeInstance.data }), wrapState({ ...prevState }));
}
});
}
if (actionSubscriber) {
this.storeDispatchActionLisitenerDispose = emitter.addListener('dispatchAction', (action, next) => {
actionSubscriber(action, next);
});
}
};
如果这个方法 subscribe 调用2次了，那么在unload 生命周期里面 this.storeUpdateLisitenerDispose 只有一个被执行注销掉Listener