I am stuck on a small problem, but been lack of logic so need your help.
I have an if statement:
func showButton() {
if viewModel.model.id == Constants.Identifiers.showId[<any>] {
//do this. Like show the button
} else {
//do that. Like hide the button
}
}
So the problem is that I want to check if viewmodel.model.id has any of the values in Constants.Identifiers.showId[]
model.id is a string, and Identifiers.showId[] is array of strings..
I know this is an easy, but... Thanks for the help!
You may use array.contains(_:) method. Documentation Link
func showButton() {
if Constants.Identifiers.showId.contains(viewModel.model.id) {
// do this. Like show the button
} else {
// do that. Like hide the button
}
}
try it
if Constants.Identifiers.showId.contains(viewModel.model.id) {
}
Hello I have array of friends this.venner
also I have array called this.convensations and output is like this.venner,
but id here is called partner_id (partner_id output is 54312, 54345, 54346 )
now I want compare if this.convensation partner_id and this.venner id if is same
something like this:
if (this.convensation in this.venner) {
//do something
} else {
// do something
}
You can use the Array.prototype.some() method.
If you wrap that in it's own checkExistsInArray function...
function checkExistsInArray(arr, compareObj){
return arr.some(function(obj){
return compareObj[Object.keys(compareObj)] === obj[Object.keys(compareObj)];
});
}
... then you should be able to use that for both arrays by passing in a custom compare object.
var friendExists = checkExistsInArray(this.venner, { id: this.friend });
var conversationExists = checkExistsInArray(this.conversations, { partner_id: this.friend });
Side Note : As others have pointed out, there are libraries out there to readily do this sort of thing. Two of the main players I'm aware of are Underscore.js and Lodash. Even if you choose not to use them, it can sometimes be helpful to see how they work under the hood when looking for a little bit of inspiration.
You can use filter,
var result = this.venner.filter(t=>t.id === '54312');
if (result.length >0) {
//do something
} else {
// do something
}
Simply you can solve this using Undescore.js _.find function
if (.find(this.friend, {"id":this.venner) {
//do something
} else {
// do something
}
I want to create a single function that will be used for total project.
It will work based on the ng-model passed into it.
For ex:-
$scope.checkBoxValueChanged=function(model) {
if($scope.model=="AA") {
$scope.model="BB";
}
else {
$scope.model="BB";
}
};
});
If i have the passed model's value as "AA" then i need to assign the passed model's value as "BB"
But what i am getting is the model value instead of model name.
Can anyone tell me how to get the model instead of model value.
Any help will be highly appreciated.
You should pass the property name (what you refer to as "model") as a string parameter.
Then you can access it using the object[key] syntax.
$scope.checkBoxValueChanged = function(propName) {
if($scope[propName] === 'AA') {
$scope[propName] = 'BB';
} else {
$scope[propName] = 'AA';
}
};
BTW, in JS, scope.model is equivalent to scope['model'], so the dot syntax won't work as you want it to.
I can successfully do this:
App.SomeCollection = Backbone.Collection.extend({
comparator: function( collection ){
return( collection.get( 'lastName' ) );
}
});
Which is nice if I want to have a collection that is only sorted by 'lastName'. But I need to have this sorting done dynamically. Sometimes, I'll need to sort by, say, 'firstName' instead.
My utter failures include:
I tried passing an extra variable specifying the variable to sort() on. That did not work. I also tried sortBy(), which did not work either. I tried passing my own function to sort(), but this did not work either. Passing a user-defined function to sortBy() only to have the result not have an each method, defeating the point of having a newly sorted backbone collection.
Can someone provide a practical example of sorting by a variable that is not hard coded into the comparator function? Or any hack you have that works? If not, a working sortBy() call?
Interesting question. I would try a variant on the strategy pattern here. You could create a hash of sorting functions, then set comparator based on the selected member of the hash:
App.SomeCollection = Backbone.Collection.extend({
comparator: strategies[selectedStrategy],
strategies: {
firstName: function () { /* first name sorting implementation here */ },
lastName: function () { /* last name sorting implementation here */ },
},
selectedStrategy: "firstName"
});
Then you could change your sorting strategy on the fly by updating the value of the selectedStrategy property.
EDIT: I realized after I went to bed :) that this wouldn't quite work as I wrote it above, because we're passing an object literal to Collection.extend. The comparator property will be evaluated once, when the object is created, so it won't change on the fly unless forced to do so. There is probably a cleaner way to do this, but this demonstrates switching the comparator functions on the fly:
var SomeCollection = Backbone.Collection.extend({
comparator: function (property) {
return selectedStrategy.apply(myModel.get(property));
},
strategies: {
firstName: function (person) { return person.get("firstName"); },
lastName: function (person) { return person.get("lastName"); },
},
changeSort: function (sortProperty) {
this.comparator = this.strategies[sortProperty];
},
initialize: function () {
this.changeSort("lastName");
console.log(this.comparator);
this.changeSort("firstName");
console.log(this.comparator);
}
});
var myCollection = new SomeCollection;
Here's a jsFiddle that demonstrates this.
The root of all of your problems, I think, is that properties on JavaScript object literals are evaluated immediately when the object is created, so you have to overwrite the property if you want to change it. If you try to write some kind of switching into the property itself it'll get set to an initial value and stay there.
Here's a good blog post that discusses this in a slightly different context.
Change to comparator function by assigning a new function to it and call sort.
// Following example above do in the view:
// Assign new comparator
this.collection.comparator = function( model ) {
return model.get( 'lastname' );
}
// Resort collection
this.collection.sort();
// Sort differently
this.collection.comparator = function( model ) {
return model.get( 'age' );
}
this.collection.sort();
So, this was my solution that actually worked.
App.Collection = Backbone.Collection.extend({
model:App.Model,
initialize: function(){
this.sortVar = 'firstName';
},
comparator: function( collection ){
var that = this;
return( collection.get( that.sortVar ) );
}
});
Then in the view, I have to M-I-C-K-E-Y M-O-U-S-E it like this:
this.collections.sortVar = 'lastVar'
this.collections.sort( this.comparator ).each( function(){
// All the stuff I want to do with the sorted collection...
});
Since Josh Earl was the only one to even attempt a solution and he did lead me in the right direction, I accept his answer. Thanks Josh :)
This is an old question but I recently had a similar need (sort a collection based on criteria to be supplied by a user click event) and thought I'd share my solution for others tackling this issue. Requires no hardcoded model.get('attribute').
I basically used Dave Newton's approach to extending native JavaScript arrays, and tailored it to Backbone:
MyCollection = Backbone.Collection.extend({
// Custom sorting function.
sortCollection : function(criteria) {
// Set your comparator function, pass the criteria.
this.comparator = this.criteriaComparator(criteria);
this.sort();
},
criteriaComparator : function(criteria, overloadParam) {
return function(a, b) {
var aSortVal = a.get(criteria);
var bSortVal = b.get(criteria);
// Whatever your sorting criteria.
if (aSortVal < bSortVal) {
return -1;
}
if (aSortVal > bSortVal) {
return 1;
}
else {
return 0;
}
};
}
});
Note the "overloadParam". Per the documentation, Backbone uses Underscore's "sortBy" if your comparator function has a single param, and a native JS-style sort if it has two params. We need the latter, hence the "overloadParam".
Looking at the source code, it seems there's a simple way to do it, setting comparator to string instead of function. This works, given Backbone.Collection mycollection:
mycollection.comparator = key;
mycollection.sort();
This is what I ended up doing for the app I'm currently working on. In my collection I have:
comparator: function(model) {
var methodName = applicationStateModel.get("comparatorMethod"),
method = this[methodName];
if (typeof(method === "function")) {
return method.call(null, model);
}
}
Now I can add few different methods to my collection: fooSort(), barSort(), and bazSort().
I want fooSort to be the default so I set that in my state model like so:
var ApplicationState = Backbone.Model.extend({
defaults: {
comparatorMethod: "fooSort"
}
});
Now all I have to do is write a function in my view that updates the value of "comparatorMethod" depending upon what the user clicks. I set the collection to listen to those changes and do sort(), and I set the view to listen for sort events and do render().
BAZINGA!!!!
I have a search controller that will look up values and render specific views according to the type of report that should be displayed. There is a weird thing happening. When I issue the $this->render the report view is not rendered. The "catch all" redirect line always is rendered... Code as follows:
public function admin_printReport() {
if (isset($this->request->data['Reports'])) {
$nons = $this->request->data['Reports'];
$res = array();
// lets lookup the noncons.....
foreach ($nons as $dat=>$vdat) {
// skip the ones that are not checked
if ($vdat == 0) {
continue;
}
// this is the temporary array that holds all of the selected report numbers > $res[] = $dat;
}
$this->loadModel('Noncon');
$this->Noncon->recursion = 0;
$results = $this->Noncon->find('all', array('conditions'=>array('Noncon.id'=>$res)));
$this->set('results', $results);
// lets do the selection now...
if (isset($this->request->data['PS'])) {
// Print summary
$this->render('summary', 'print');
} elseif (isset($this->request->data['PD'])) {
// Print detail
$this->render('detail', 'print');
} elseif (isset($this->request->data['PDH'])) {
// Print detail with history
$this->render('detailhistory', 'print');
}
}
// catch all if the render does not work....
$this->redirect(array('controller'=>'noncons', 'action'=>'search','admin'=>true));
}
Any Ideas?
I just figured it out....
for each $this->render, add return. For example:
return $this->render('summary', 'print');
I've just add a similar problem.
In a controller, that has an ajax submit, it was not submitting the render.
$this->render($viewName, 'ajax');
Using return didn't helped.
The problem was that I added
$this->render('add');
at the end of the controller, although it was not necessary since the controller name is add and the autoRender is default (true to automatically render the view with the same name of the controller).
Hope this helps someone else.