I have my javascript code like this . Inside that I have an init() function and in that function I have an options JSON object and in that object I have a function defined as objectselected(). How I call that function in a button click event
I have tried like this WorkFlow.init().options.Objectselected() but it is not working,
var WorkFlow = {
connectionData: [],
selectedTouchpoints: [],
init: function () {
var options = {
palleteId: "myPaletteElement",
elementId: "playAreaContainer",
TextStoreList: ['One', 'Two', 'Three'],
LinkTextStoreList: $('#drpLinkType option').map(function () {
return this.text;
}).get(),
shapeList: ['RoundedRectangle', 'Circle', 'Rectangle', 'Ellipse', 'Square', 'Diamond', 'Card', 'Database'],
diagramUpdate: function (e) {
},
objectSelected: function (e) {
},
linkUpdate: function (e) {
},
initialize: function () {
}
myGraph = new Graph(options);
options.initialize();
},
}
How to call that function.
One way around is you can return options and than call it.
init: function () {
var options = {
...your code..}
return options;
},
and call it than
var options = WorkFlow.init();
options.Objectselected();
As it stands, you have no access to options because it's a local variable - that is, local to its scope.
To access its contents, you'll need to return it from init().
Think about it:
WorkFlow.init()
Currently this returns undefined, because your init() returns nothing. You're trying to chain like in jQuery, but that relies on the API always returning the instance. Your path finds a dead-end at init().
To fix this, have init() return options - or at least the part of it you want to access from outside - an "export".
So (basic example)
init: function() {
var options {
my_func: function() { }, //<-- we want outside access to this
private: 'blah' //<-- this can stay private - leave it out of the export
}
//return an export, exposing only what we need to
return {
my_func: options.my_func
}
}
You need to return options as it is inside init function's scope
var WorkFlow = {
connectionData: [],
selectedTouchpoints: [],
init: function () {
var options = {
palleteId: "myPaletteElement",
elementId: "playAreaContainer",
TextStoreList: ['One', 'Two', 'Three'],
LinkTextStoreList: $('#drpLinkType option').map(function () {
return this.text;
}).get(),
shapeList: ['RoundedRectangle', 'Circle', 'Rectangle', 'Ellipse', 'Square', 'Diamond', 'Card', 'Database'],
diagramUpdate: function (e) {
},
objectSelected: function (e) {
},
linkUpdate: function (e) {
},
initialize: function () {
}
myGraph = new Graph(options);
options.initialize();
return options;
},
}
And call it as WorkFlow.init().objectSelected();
Building on Patrick's comment, you'd need to return options from the init function:
var WorkFlow = {
connectionData: [],
selectedTouchpoints: [],
init: function () {
var options = {
palleteId: "myPaletteElement",
...
options.initialize();
return options;
},
}
Related
Here is the my question
var panel = {
_pnlHeaderContainer: $('.panelHeader'),
_pnlHeaderString:"",
//private method
_Write: function (pnlHeaderString) { return this._pnlHeaderContainer.html(pnlHeaderString); },
Clear: function () { return this._pnlBaslikContainer.html(""); },
// _fake:this,
Header: {
AddEvent:"Add Event",
Calendar: "Calendar",
}
};
what I wanna achieve is using the _Write method in Header object
something like this
Header: {
AddEvent:this._Write("Add Event"),
Calendar: "Calendar",
}
trying to run this code like this panel.Header.AddEvent; but it says me Write is not a function
I like to provide a context when creating a class
function Panel(){
var context = this;
this._pnlHeaderContainer = $('.panelHeader');
this._pnlHeaderString = "";
this._Write = function(pnlHeaderString){
return context._pnlHeaderContainer.html(pnlHeaderString);
};
this.Clear = function(){
return context._pnlBaslikContainer.html("");
};
this.Header = {
AddEvent: function(){ return context._Write("Add Event"); },
Calendar: "Calendar",
};
}
var panelObject = new Panel();
// Do whatever you want...
panelObject.Header.AddEvent();
I have the following code:
{
data: function () {
return {
questions: [],
sendButtonDisable: false,
}
},
methods: {
postQuestionsContent: function () {
var that = this;
that.sendButtonDisable = true;
},
},
},
I need to change sendButtonDisable to true when postQuestionsContent() is called. I found only one way to do this; with var that = this;.
Is there a better solution?
Inside methods if you don't have another scope defined inside, you can access your data like that:
this.sendButtonDisable = true;
but if you have a scope inside the function then in vue is a common usage of a variable called vm (stands for view model) at the beginning of the function, and then just use it everywhere like:
vm.sendButtonDisable = false;
An example of vm can be seen in the Vue official documentation as well.
complete example:
data: function () {
return {
questions: [],
sendButtonDisable : false
}
},
methods: {
postQuestionsContent : function() {
// This works here.
this.sendButtonDisable = true;
// The view model.
var vm = this;
setTimeout(function() {
// This does not work, you need the outside context view model.
//this.sendButtonDisable = true;
// This works, since wm refers to your view model.
vm.sendButtonDisable = true;
}, 1000);
}
}
It depends on how you call your postQuestionsContent method (if you call it asynchronously, you might need to bind the this context).
In most cases, you should be able to access it using this.$data.YOURPROPNAME, in your case this.$data.sendButtonDisable:
data: function () {
return {
questions: [],
sendButtonDisable : false
}
},
methods:
{
postQuestionsContent : function()
{
this.$data.sendButtonDisable = true;
}
}
Try this instead
...
methods:
{
postQuestionsContent ()
{
this.sendButtonDisable = true;
}
}
Registering your methods in the above manner should resolve the issue.
I tried both this.$data.sendButtonDisable and vm.sendButtonDisable and did not work for me.
But I got it working with outer_this = this, something like:
methods: {
sendForm(){
var outer_this;
outer_this = this;
$.ajax({
url: "email.php",
type: "POST",
dataType: "text",
data: {
abc: "..."
},
success: function(res){
if(res){
//...
outer_this.sendButtonDisable = false;
}else{
//...
}
}
});
}
},
I am trying to create a flux store for a React app I am building. I am using an object-assign polyfill npm package and Facebook's Flux library.
Initially I was getting the error "Cannot read property '_data' of null' error in the console which was refering to var currIds = this._data.map(function(m){return m.id;});. That method is currently the only one being called directly. I then did console.log(this) which returned "null".
I find this strange. What is going on?
My code:
var Assign = require('object-assign');
var EventEmitterProto = require('events').EventEmitter.prototype;
var CHANGE_EVENT = 'CHANGE';
var StoreMethods = {
init: function() {},
set: function (arr) {
console.log(this);
var currIds = this._data.map(function(m){return m.id;});
arr.filter(function (item){
return currIds.indexOf(item.id) === -1;
}).forEach(this.add.bind(this));
},
add: function(item){
console.log(this);
this._data.push(item);
},
all: function() {
return this._data;
},
get: function(id){
return this._data.filter(function(item){
return item.cid === id;
})[0];
},
addChangeListener: function(fn) {
this.on(CHANGE_EVENT, fn);
},
removeChangeListener: function(fn) {
this.removeListener(CHANGE_EVENT, fn);
},
emitChange: function() {
this.emit(CHANGE_EVENT);
},
bind: function(actionType, actionFn) {
if(this.actions[actionType]){
this.actions[actionType].push(actionFn);
} else {
this.actions[actionType] = [actionFn];
}
}
};
exports.extend = function(methods) {
var store = {
_data: [],
actions: {}
};
Assign(store, EventEmitterProto, StoreMethods, methods);
store.init();
require('../dispatcher').register(function(action){
if(store.actions[action.actionType]){
store.actions[action.actionType].forEach(function(fn){
fn.call(null, action.data);
})
}
});
return store;
};
I can't see where set is called, however your this can be null if the function is invoked through call (see here) or apply, and your first argument is null.
This also happens in your require.register callback:
fn.call(null, action.data) //First parameter is your 'this'.
I have an app-object constructer that looks like this:
var app = function(loadedsettings) {
return {
init: function() {
this.loop();
},
loop: function() {
this.update();
window.requestAnimationFrame(this.loop);
},
update: function() {
//loop through settings and call update on every object.
},
settings: [
//array of settings objects, all with update methods.
]
};
}
Then when I do:
var theApp = app(settings);
theApp.init();
I get:
Uncaught TypeError: Object [object global] has no method 'update'
because when requestAnimationFrame is called, the this-value inside the loop function is set to window.
Does anybody know how to call requestAnimatinFrame with the 'theApp' object set as the this-value?
You can create a bound function (with a fixed this), and pass that to requestAnimationFrame:
var app = function(loadedsettings) {
return {
init: function() {
this.loop();
},
loop: function() {
this.update();
window.requestAnimationFrame(this.loop.bind(this));
},
update: function() {
//loop through settings and call update on every object.
},
settings: [
//array of settings objects, all with update methods.
]
};
}
I think that a browser which supports requestAnimationFrame will also support Function.prototype.bind, but in case you come across one that doesn't, there are polyfills available.
You need to cache a reference to this:
var app = function(loadedsettings) {
var self = this;
return {
init: function() {
self.loop();
},
loop: function() {
self.update();
window.requestAnimationFrame(self.loop);
},
** snip **
...
I have the following object:
var party =
{
food:
{
serve: function () {
// I want to call turnOff method from here
}
cleanUp: function () {
}
}
music:
{
turnOff: function () {
}
}
}
So as the comment points out, I want to call the turnOff method from the music object, how can I do this? this refers to the food object but I need to access the music object...
var party =
{
food:
{
serve: function () {
party.music.turnOff();
},
cleanUp: function () {
}
},
music:
{
turnOff: function () {
}
}
}
Use a constructor instead of a literal with a variable referencing the parent object
var party = new (function()
{
var self = this;
this.food =
{
serve: function () {
self.music.turnoff();
},
cleanUp: function () {
}
}
this.music =
{
turnOff: function () {
}
}
})();
Call it as party.music.turnOff().
FYI, your above code block isn't valid. You're missing some commas - after the serve and food closing braces.