I have three functions i'm trying to run, the first two are doing some async stuff that need data for the third to use. I want the third function to fire only when 1 and 2 are both done. this is the general structure but the final function is firing before 1 and 2 finish.
function run() {
var data1 = {};
var data2 = {};
$.when(first(), second()).done(constructData());
function first() {
var d = new $.Deferred();
//do a bunch of stuff async
data1 = {};
d.resolve();
}
function second() {
var d = new $.Deferred();
//do a bunch of stuff async
data2 = {};
d.resolve();
}
function constructData() {
//do stuff with data1 and data2
}
}
Answer was to not call construct data immediately
$.when(first(), second()).done(constructData);
You should return promise object. You also have an error in this line:
$.when(first(), second()).done(constructData());
it should be
$.when(first(), second()).done(constructData); // don't call constructData immediately
So all together it could be:
function run() {
var data1 = {};
var data2 = {};
$.when(first(), second()).done(constructData);
function first() {
return $.Deferred(function() { // <-- see returning Deferred object
var self = this;
setTimeout(function() { // <-- example of some async operation
data1 = {func: 'first', data: true};
self.resolve(); // <-- call resolve method once async is done
}, 2000);
});
}
function second() {
return $.Deferred(function() {
var self = this;
setTimeout(function() {
data2 = {func: 'second', data: true};
self.resolve();
}, 3000);
});
}
function constructData() {
//do stuff with data1 and data2
console.log(data1, data2);
}
}