Vue 等效于 setTimeout? ？

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You can use Vue.nextTick

addToBasket: function(){
item = this.photo;
this.$http.post('/api/buy/addToBasket', item);
this.basketAddSuccess = true;
Vue.nextTick(() =>{
this.basketAddSuccess = false;
});
}

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最佳答案

Arrow Function

The best and simplest way to solve this problem is by using an arrow function () => {}:

    addToBasket() {
var item = this.photo;
this.$http.post('/api/buy/addToBasket', item);
this.basketAddSuccess = true;
// now 'this' is referencing the Vue object and not the 'setTimeout' scope
setTimeout(() => this.basketAddSuccess = false, 2000);
}

This works because the this of arrow functions is bound to the this of its enclosing scope- in Vue, that's the parent/ enclosing component. Inside a traditional function called by setTimeout, however, ABC0 refers to the window object (which is why you ran into errors when you tried to access this.basketAddSuccess in that context).

Argument Passing

Another way of doing this would be passing this as an arg to your function through setTimeout's prototype using its setTimeout(callback, delay, arg1, arg2, ...) form:

    addToBasket() {
item = this.photo;
this.$http.post('/api/buy/addToBasket', item);
this.basketAddSuccess = true;
//Add scope argument to func, pass this after delay in setTimeout
setTimeout(function(scope) {
scope.basketAddSuccess = false;
}, 2000, this);
}

(It's worth noting that the arg passing syntax is incompatible with IE 9 and below, however.)

Local Variable

Another possible, but less eloquent and less encouraged, way is to bind this to a var outside of setTimeout:

    addToBasket() {
item = this.photo;
this.$http.post('/api/buy/addToBasket', item);
this.basketAddSuccess = true;
//Declare self, which is accessible inside setTimeout func
var self = this;
setTimeout(function() {
self.basketAddSuccess = false;
}, 2000);
}

Using an arrow function would eliminate the need for this extra variable entirely however, and really should be used unless something else is preventing its use.

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after encountering the same issue, I ended up on this thread. For future generation's sake: The current up-most voted answer, attempts to bind "this" to a variable in order to avoid changing the context when invoking the function which is defined in the setTimeout.

An alternate and more recommended approach(using Vue.JS 2.2 & ES6) is to use an arrow function in order to bind the context to the parent (Basically "addToBasket"'s "this" and the "setTimeout"'s "this" would still refer to the same object):

addToBasket: function(){
item = this.photo;
this.$http.post('/api/buy/addToBasket', item);
this.basketAddSuccess = true;
setTimeout(() => {
this.basketAddSuccess = false;
}, 2000);
}

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Add bind(this) to your setTimeout callback function

setTimeout(function () {
this.basketAddSuccess = false
}.bind(this), 2000)

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vuejs 2

first add this to methods

methods:{
sayHi: function () {
var v = this;
setTimeout(function () {
v.message = "Hi Vue!";
}, 3000);
}

after that call this method on mounted

mounted () {
this.sayHi()
}

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use this.animationStop, not use this.animationStop ~~( )~~

animationRun(){
this.sliderClass.anim = true;
setTimeout(this.animationStop, 500);
},

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If you want to use the this keyword in your function, you need to write the setTimeout function in ES6

setTimeout(() => {
this.filters.max_budget_gt_eq = this.budgetHigherValue;
}, 1000);

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Kevin Muchwat above has the BEST answer, despite only 10 upvotes and not selected answer.

setTimeout(function () {
this.basketAddSuccess = false
}.bind(this), 2000)

Let me explain WHY.

"Arrow Function" is ECMA6/ECMA2015. It's perfectly valid in compiled code or controlled client situations (cordova phone apps, Node.js), and it's nice and succinct. It will even probably pass your testing!

However, Microsoft in their infinite wisdom has decided that Internet Explorer WILL NOT EVER SUPPORT ECMA2015!

Their new Edge browser does, but that's not good enough for public facing websites.

Doing a standard function(){} and adding .bind(this) however is the ECMA5.1 (which IS fully supported) syntax for the exact same functionality.

This is also important in ajax/post .then/else calls. At the end of your .then(function){}) you need to bind(this) there as well so: .then(function(){this.flag = true}.bind(this))

I would have added this as a comment to Kevin's response, but for some silly reason it takes less points to post replies than to comment on replies

DO NOT MAKE THE SAME MISTAKE I MADE!

I code on a Mac, and used the 48 points upvoted comment which worked great! Until I got some calls on my scripts failing and I couldn't figure out why. I had to go back and update dozens of calls from arrow syntax to function(){}.bind(this) syntax.

Thankfully I found this thread again and got the right answer. Kevin, I am forever grateful.

As per the "Accepted answer", that has other potential issues dealing with additional libraries (had problems properly accessing/updating Vue properties/functions)

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ES6 can bind 'this'

setTimeout(() => {


},5000);

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There's no need for bind(this) when you are using arrow functions:

  setTimeout( ()=> {
// some code
}, 500)

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It is likely a scope issue. Try the following instead:

addToBasket: function(){
item = this.photo;
this.$http.post('/api/buy/addToBasket', item);
this.basketAddSuccess = true;
var self = this;
setTimeout(function(){
self.basketAddSuccess = false;
}, 2000);
}

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