The component:
https://ant.design/components/tree-select/
There is no example with the loadData option.
async getChildren(node) {
console.log(node);
let r = $.get("/tree", {id: node.value})
console.log(await r); // request works
return r;
}
With this code I just see the tree loading and nothing happens. Not an error, but the child nodes are not appended to the tree.
If I don't return a Promise, I get a huge error and a blank page.
this is an example of loadData function:
onLoadData = (treeNode) => {
console.log('load data...');
return new Promise((resolve) => {
setTimeout(() => {
const treeData = [...this.state.treeData];
getNewTreeData(treeData, treeNode.props.eventKey, generateTreeNodes(treeNode), 2);
this.setState({ treeData });
resolve();
}, 500);
});
}
You can find it here with more in-deep examples
To make it clearer:
TreeData is an Array of TreeNode
source
antd tree select uses rc-tree because antd is built on top of rc-components you can see the source
For lazy load you need to manipulate the treeNode, what above snippet
does is: everytime loaded new data it will be a treeNode object, and
will call the onLoadData() callback where you provide the code what
to do with that node. (the sample just append to the state's treeData
variable]
Related
I know the rule that this object cant be changed but need an alternative method .
var that= this
axios.get('http://ec2-54-165-240-14.compute-1.amazonaws.com:3000/api/foodItem').then(function(data){
console.log("inside axios ",data)
that.setState({
items : data,
});
var curGroupId = that.props.cartReducer.val;
var items = that.state.items ;
var curItems= [];
for(var i in items){
if(items[i].food_group_id==curGroupId){
curItems.push(items[i]);
}
}
that.setState({
curItems : curItems
})
}).catch(function(err){
console.log(err)
})
I want to update the state in this object which is not accessible inside the then function and therefore i have stored this object in that before the function but i want to apply changes in the this object.
You can try using an arrow function, that way you will have access to this inside the inner functions.
axios.get('http://ec2-54-165-240-14.compute-1.amazonaws.com:3000/api/foodItem')
.then((data) => {
console.log("inside axios ",data)
this.setState({ // <---- references to the parent scope
items : data,
});
var curGroupId = that.props.cartReducer.val;
var items = that.state.items ;
var curItems= [];
for(var i in items){
if(items[i].food_group_id==curGroupId){
curItems.push(items[i]);
}
}
this.setState({ // this too ;)
curItems : curItems
})
}).catch((err) => {
console.log(err)
})
An arrow function will use the same scope as the parent function, pretty handy for these situations.
One more thing, I don't recommend calling setState multiple times. You should call it only once at the end of the callback, when all your data is ready to use.
Yo! I'm using Redux and Normalizr. The API I'm working with sends down objects that look like this:
{
name: 'Foo',
type: 'ABCD-EFGH-IJKL-MNOP'
}
or like this
{
name: 'Foo2',
children: [
'ABCD-EFGH-IJKL-MNOP',
'QRST-UVWX-YZAB-CDEF'
]
}
I want to be able to asynchronously fetch those related entities (type and children) when the above objects are accessed from the state (in mapStateToProps). Unfortunately, this does not seem to mesh with the Redux way as mapStateToProps is not the right place to call actions. Is there an obvious solution to this case that I'm overlooking (other than pre-fetching all of my data)?
Not sure that I have correctly understood your use-case, but if you want to fetch data, one simple common way is to trigger it from a React component:
var Component = React.createClass({
componentDidMount: function() {
if (!this.props.myObject) {
dispatch(actions.loadObject(this.props.myObjectId));
}
},
render: function() {
const heading = this.props.myObject ?
'My object name is ' + this.props.myObject.name
: 'No object loaded';
return (
<div>
{heading}
</div>
);
},
});
Given the "myObjectId" prop, the component triggers the "myObject" fetching after mounting.
Another common way would be to fetch the data, if it's not already here, from a Redux async action creator (see Redux's doc for more details about this pattern):
// sync action creator:
const FETCH_OBJECT_SUCCESS = 'FETCH_OBJECT_SUCCESS';
function fetchObjectSuccess(objectId, myObject) {
return {
type: FETCH_OBJECT_SUCCESS,
objectId,
myObject,
};
}
// async action creator:
function fetchObject(objectId) {
return (dispatch, getState) => {
const currentAppState = getState();
if (!currentAppState.allObjects[objectId]) {
// fetches the object if not already present in app state:
return fetch('some_url_.../' + objectId)
.then(myObject => (
dispatch(fetchObjectSuccess(objectId, myObject))
));
} else {
return Promise.resolve(); // nothing to wait for
}
};
}
I have been working on a end-to-end test using Webdriver I/O from Jasmine. One specific scenario has been giving me significant challenges.
I have a page with 5 links on it. The number of links actually challenges as the page is dynamic. I want to test the links to see if each links' title matches the title of the page that it links to. Due to the fact that the links are dynamically generated, I cannot just hard code tests for each link. So, I'm trying the following:
it('should match link titles to page titles', function(done) {
client = webdriverio.remote(settings.capabilities).init()
.url('http://www.example.com')
.elements('a').then(function(links) {
var mappings = [];
// For every link store the link title and corresponding page title
var results = [];
for (var i=0; i<links.value.length; i++) {
mappings.push({ linkTitle: links.value[0].title, pageTitle: '' });
results.push(client.click(links.value[i])
.getTitle().then(function(title, i) {
mappings[i].pageTitle = title;
});
);
}
// Once all promises have resolved, compared each link title to each corresponding page title
Promise.all(results).then(function() {
for (var i=0; i<mappings.length; i++) {
var mapping = mappings[i];
expect(mapping.linkTitle).toBe(mapping.pageTitle);
}
done();
});
});
;
});
I'm unable to even confirm if I'm getting the link title properly. I believe there is something I entirely misunderstand. I am not even getting each links title property. I'm definately not getting the corresponding page title. I think I'm lost in closure world here. Yet, I'm not sure.
UPDATE - NOV 24
I still have not figured this out. However, i believe it has something to do with the fact that Webdriver I/O uses the Q promise library. I came to this conclusion because the following test works:
it('should match link titles to page titles', function(done) {
var promise = new Promise(function(resolve, reject) {
setTimeout(function() { resolve(); }, 1000);
});
promise.then(function() {
var promises = [];
for (var i=0; i<3; i++) {
promises.push(
new Promise(function(resolve, reject) {
setTimeout(function() {
resolve();
}, 500);
})
);
}
Promise.all(promises).then(function() {
expect(true).toBe(true)
done();
});
});
However, the following does NOT work:
it('should match link titles to page titles', function(done) {
client = webdriverio.remote(settings.capabilities).init()
.url('http://www.example.com')
.elements('a').then(function(links) {
var mappings = [];
// For every link store the link title and corresponding page title
var results = [];
for (var i=0; i<links.value.length; i++) {
mappings.push({ linkTitle: links.value[0].title, pageTitle: '' });
results.push(client.click(links.value[i])
.getTitle().then(function(title, i) {
mappings[i].pageTitle = title;
});
);
}
// Once all promises have resolved, compared each link title to each corresponding page title
Q.all(results).then(function() {
for (var i=0; i<mappings.length; i++) {
var mapping = mappings[i];
expect(mapping.linkTitle).toBe(mapping.pageTitle);
}
done();
});
})
;
});
I'm not getting any exceptions. Yet, the code inside of Q.all does not seem to get executed. I'm not sure what to do here.
Reading the WebdriverIO manual, I feel like there are a few things wrong in your approach:
elements('a') returns WebElement JSON objects (https://code.google.com/p/selenium/wiki/JsonWireProtocol#WebElement_JSON_Object) NOT WebElements, so there is no title property thus linkTitle will always be undefined - http://webdriver.io/api/protocol/elements.html
Also, because it's a WebElement JSON object you cannot use it as client.click(..) input, which expects a selector string not an object - http://webdriver.io/api/action/click.html. To click a WebElement JSON Object client.elementIdClick(ID) instead which takes the ELEMENT property value of the WebElement JSON object.
When a client.elementIdClick is executed, the client will navigate to the page, trying to call client.elementIdClick in the next for loop cycle with next ID will fail, cause there is no such element as you moved away from the page. It will sound something like invalid element cache.....
So, I propose another solution for your task:
Find all elements as you did using elements('a')
Read href and title using client.elementIdAttribute(ID) for each of the elements and store in an object
Go through all of the objects, navigate to each of the href-s using client.url('href'), get the title of the page using .getTitle and compare it with the object.title.
The source I experimented with, not run by Jasmine, but should give an idea:
var client = webdriverio
.remote(options)
.init();
client
.url('https://www.google.com')
.elements('a')
.then(function (elements) {
var promises = [];
for (var i = 0; i < elements.value.length; i++) {
var elementId = elements.value[i].ELEMENT;
promises.push(
client
.elementIdAttribute(elementId, 'href')
.then(function (attributeRes) {
return client
.elementIdAttribute(elementId, 'title')
.then(function (titleRes) {
return {href: attributeRes.value, title: titleRes.value};
});
})
);
}
return Q
.all(promises)
.then(function (results) {
console.log(arguments);
var promises = [];
results.forEach(function (result) {
promises.push(
client
.url(result.href)
.getTitle()
.then(function (title) {
console.log('Title of ', result.href, 'is', title, 'but expected', result.title);
})
);
});
return Q.all(promises);
});
})
.then(function () {
client.end();
});
NOTE:
This fails to solve your problem, when the links trigger navigation with JavaScript event handlers not the href attributes.
I have a strategy question.
I want to change data in my website using signalR and display changed data using react. My question would be: How to perform data binding between signalR and react?
My first clue is the following:
signalR:
chat.client.addMessage = function (name, message) {
chatHistory.push({ Author: name, Text: message }); //here I change global variable chatHistory
};
react:
var CommentList = React.createClass({some class here});
var CommentBox = React.createClass({
componentRefresh: function () {
this.setState({ data: chatHistory });
},
getInitialState: function () {
return { data: chatHistory };
},
componentDidMount: function () {
this.componentRefresh();
setInterval(this.componentRefresh, this.props.interval);
},
render: function () {
return (
React.DOM.div(null,
CommentList({ data: this.state.data })
)
);
}
});
React.renderComponent(
CommentBox({ interval: 2000 }),
document.getElementById('content')
);
in react commentBox component I feed global chatHistory and ask for a new value every 2 seconds.
Is there more elegant way of doing it?
and how to avoid redrawing of CommentBox if chatHistory variable wasn't changed?
Your approach of maintaining state in CommentBox is fine. As your component base grows, it might become complicated to maintain self-updating components though. I recommend investigating the Flux architecture the React team designed and their Todo MVC Flux example in particular.
You could implement shouldComponentUpdate to prevent React from re-rendering the CommentBox if you know state hasn't changed. Also, you should keep a reference to the interval so you can clear it when the CommentBox is unmounted otherwise it will go on polling after the component is removed.
var CommentBox = React.createClass({
...
componentDidMount: function() {
this.componentRefresh();
this._interval = setInterval(this.componentRefresh, this.props.interval);
},
componentWillUnmount: function() {
clearInterval(this._interval);
this._interval = null;
},
shouldComponentUpdate: function(nextProps, nextState) {
// Do a deep comparison of `chatHistory`. For example, use
// Underscore's `isEqual` function.
return !_.isEqual(this.state.chatHistory, nextState.chatHistory);
},
...
});
I'm using the following code in my view to fetch my collection from the server:
initialize: function () {
_this = this;
this.collection.fetch({
success : function(collection, response) {
_.each(response, function(i){
var todo = new TodosModel({
id: i.id,
content: i.content,
completed: i.completed
});
// Add to collection
_this.collection.add(todo);
// Render
_this.render(todo);
});
},
error : function(collection, response) {
console.log('ERROR GETTING COLLECTION!');
}
});
},
Which seems to work - here's the output from my server:
{
"0": {
"id": 1,
"content": "one",
"completed": false
},
"3": {
"id": 4,
"content": "two",
"completed": true
},
"4": {
"id": 5,
"content": "tester",
"completed": false
}
}
Except for the fact that if I log out my collection there is a null entry in the first position:
Which then causes issues as if I add an item it takes the ID of the last element. I'm new to backbone and am hoping I'm just missing something simple.
Here's my crack at a quick run through of your code. I haven't tested anything so there might be typos. I'm still not sure where the stray empty model is coming from but if you restructure your application as outlined below, I suspect the problem will go away.
The model and collection look okay so let us have a look at your view.
el: $('#todos'),
listBlock: $('#todos-list'),
newTodoField: $('#add input'),
//...
template: $('#todo-template').html(),
//...
events: { /* ... */ },
These should be okay but you need to ensure that all those elements are in the DOM when your view "class" is loaded. Usually you'd compile the template once:
template: _.template($('#todo-template').html()),
and then just use this.template as a function to get your HTML. I'll assume that template is a compiled template function below.
initialize: function () {
_this = this;
You have an accidental global variable here, this can cause interesting bugs. You want to say var _this = this;.
this.el = $(this.el);
Backbone already gives you a jQuery'd version of el in $el so you don't need to do this, just use this.$el.
this.collection.fetch({
success : function(collection, response) {
_.each(response, function(i) {
var todo = new TodosModel({ /* ... */ });
// Add to collection
_this.collection.add(todo);
// Render
_this.render(todo);
});
},
//...
The collection's fetch will add the models to the collection before the success handler is called so you don't have to create new models or add anything to the collection. Generally the render method renders the whole thing rather than rendering just one piece and you bind the view's render to the collection's "reset" event; the fetch call will trigger a "reset" event when it has fetched so the usual pattern looks like this:
initialize: function() {
// So we don't have to worry about the context. Do this before you
// use `render` or you'll have reference problems.
_.bindAll(this, 'render');
// Trigger a call to render when the collection has some stuff.
this.collection.on('reset', this.render);
// And go get the stuff we want. You can put your `error` callback in
// here if you want it, wanting it is a good idea.
this.collection.fetch();
}
Now for render:
render: function (todo) {
var templ = _.template(this.template);
this.listBlock.append(templ({
id: todo.get('id'),
content: todo.get('content'),
completed: todo.get('completed')
}));
// Mark completed
if(todo.get('completed')) {
this.listBlock.children('li[data-id="'+todo.get('id')+'"]')
.addClass('todo-completed');
}
}
Normally this would be split into two pieces:
render to render the whole collection.
Another method, say renderOne, to render a single model. This also allows you to bind renderOne to the collection's "add" event.
So something like this would be typical:
render: function() {
// Clear it out so that we can start with a clean slate. This may or
// may not be what you want depending on the structure of your HTML.
// You might want `this.listBlock.empty()` instead.
this.$el.empty();
// Punt to `renderOne` for each item. You can use the second argument
// to get the right `this` or add `renderOne` to the `_.bindAll` list
// up in `initialize`.
this.collection.each(this.renderOne, this);
},
renderOne: function(todo) {
this.listBlock.append(
this.template({
todo: todo.toJSON()
})
)
// Mark completed
if(todo.get('completed')) {
this.listBlock.find('li[data-id="' + todo.id + '"]')
.addClass('todo-completed');
}
}
Notice the use of toJSON to supply data to the template. Backbone models and collections have a toJSON method to give you a simplified version of the data so you might as well use it. The model's id is available as an attribute so you don't have to use get to get it. You could (and probably should) push the todo-completed logic into the template, just a little
<% if(completed) { %>class="completed"<% } %>
in the right place should do the trick.
addTodo: function (e) {
//...
var todo = new TodosModel({
id: todoID,
content: todoContent,
completed: todoCompleted
});
this.render(todo);
todo.save();
_this.collection.add(todo);
You could bind renderOne to the collection's "add" event to take care of rendering the new model. Then use the save callbacks to finish it off:
var _this = this;
var todo = new TodosModel({ /* ... */ });
todo.save({}, {
wait: true,
success: function(model, response) {
// Let the events deal with rendering...
_this.collection.add(model);
}
});
Again, an error callback on the save might be nice.
completeTodo: function (e) {
//...
todo.save({
completed: todoCompleted
});
}
The save call here will trigger a 'change:completed' event so you could bind to that to adjust the HTML.
removeTodo: function (e) {
//...
}
The destroy call will trigger a "destroy" event on the model and on the collection:
Any event that is triggered on a model in a collection will also
be triggered on the collection directly, for convenience. This
allows you to listen for changes to specific attributes in any model
in a collection, [...]
So you could listen for "destroy" events on the collection and use those to remove the TODO from the display. And destroying the model should remove it from the collection without your intervention.
printColl: function () {
this.collection.each(function (todo) {
console.log('ID: '+todo.get('id')+' | CONTENT: '+todo.get('content')+' | COMPLETED: '+todo.get('completed'));
});
}
You could just console.log(this.collection.toJSON()) instead,
you'd have to click around a little to open up the stuff in the
console but you wouldn't miss anything that way.
All the event binding for the collection would take place in your
view's initialize method. If you're going to remove the view then
you'd want to override the remove to unbind from the collection
to prevent memory leaks:
remove: function() {
// Call this.collection.off(...) to undo all the bindings from
// `initialize`.
//...
// Then do what the default `remove` does.
this.$el.remove()
}
You could also use a separate view for each TODO item but that might be overkill for something simple.