Polymer: How to pass sub-object as binding to the custom element - polymer

Suppose I have created a custom element as follow:
<chat-container messages="{{ messages }}"></chat-container>
messages is an array containing chat messages related to any particular thread or contact.
Now, in my app.js, I have this kind of message array which contains all messages by thread identifiers. How can I pass the messages related to any particular thread identifier(i.e name='Rajat') to <chat-container> element? I have tried nearly all combinations and still nothing is making sense.
app.messages = [
{name: 'Rajat', messages: [{id: 1,message: 'Hello'},{id: 3,message: 'Hello 2'}]},
{name: 'Himesh', messages: [{id: 2,message: 'Hello'}]},
{name: 'David', messages: [{id: 4,message: 'Hello'}]}
]
I tried to do:
<chat-container messages="{{ app.messages.filter(function(e) { return e.name === 'Rajat'; })[0].messages }}"></chat-container>
and it did not work.

Polymer doesn't support such complex binding expression. Move the filter code to a function and call that function from the binding expression. Binding expressions only support .``!, ()
<chat-container messages="{{filter('name', 'Rajat')}}"></chat-container>
where the parent element has a function named filter()

Related

ImmutableJs - compare objects but for one property

I am converting a shopping basket to an immutable structure.
Is there an easy way with immutablejs to see if an immutable object already exists within an immutable list EXCEPT for one object property 'quantity' which could be different? List example:
[{
id: 1,
name: 'fish and chips',
modifiers: [
{
id: 'mod1',
name: 'Extra chips'
}
],
quantity: 2
},{
id: 2,
name: 'burger and chips',
modifiers: [
{
id: 'mod1',
name: 'No salad'
}
],
quantity: 1
}]
Now, say I had another object to put in the list. But I want to check if this exact item with modifiers exists in the list already? I could just do list.findIndex(item => item === newItem) but because of the possible different quantity property then it wont work. Is there a way to === check apart from one property? Or any way to do this without having to loop through every property (aside from quantity) to see if they are the same?
Currently, I have an awful nested loop to go through every item and check every property to see if it is the same.
Well this should work-
list.findIndex(item => item.delete("quantity").equals(newItem.delete("quantity"))
The equals method does deep value comparison. So once you delete the quantity, you are comparing all values that matter.
PS: please ignore code formatting, I am on SO app.
PPS: the above code is not optimal, you should compare a pre-trimmed newItem inside the arrow function instead of trimming it there.

ExtJS 5.0 Forms generated/driven by a store

I would like to create a Form in ExtJS 5.0 completely based on a Store. Every store item represents a "line in the form". A "line" consists three or more form widgets.
Basically this is a search panel, where you define search conditions. Every condition consits of: FieldName selector, an operator selector, and a widget to write/select a condition operand. For example search for people with:
name starting with Joe (FieldName:name, operator:starting with, widget:textfield)
birtday before 1980.01.01. (FieldName:birthday, operator:before, widget:datepicker)
I get the conditions in JSON, and load them in a Store. I would like to dynamically generate the form based on this store, make modifications in the form, and ask the Store for a new JSON with the modifications (new conditions, etc).
I have problems with the first step: simply generate form widgets based on store content.
How can this be done?
I'm going to assume here that the JSON data represents a variety of dynamic data, and you can't simply use a pre-canned control like a grid, or a fixed form.
What you need to do is to make your own container class, which dynamically creates widgets based on the JSON content. You'll have to write this yourself, of course.
One extreme is to make your JSON content in the store be valid arguments to, say, Ext.widget - but that's probably not feasible, or even desirable.
For a more middling position, use the JSON data to determine, based on conditions, what widgets to add.
As a rough outline, you want something like this:
Ext.define('MyFormContainer', {
extend: 'Ext.form.FormPanel',
config: {
// A store or MixedCollection of JSON data objects, keyable by id.
formData: null
},
layout: 'vbox',
initComponent: function() {
this.callParent(arguments);
this.getFormData().each(this.addField, this)
},
addField: function(fieldData) {
var widgetConfig = this.buildWidgetConfig(fieldData);
this.add(widgetConfig);
},
buildWidgetConfig: function(fieldData) {
// The heart of the factory. You need a way to determine what sort of widget to make for
// the field. For the example config, a fieldset with three fields would probably be
// appropriate:
var fieldSet = { xtype: 'fieldset', layout: 'hbox' };
var items = [];
items[0] = { xtype: 'textfield', name: fieldData['FieldName'] };
// this would be a link to a custom widget to handle the operator. Or maybe you could
// just spit out text, if it's not meant to be alterable.
items[1] = { xtype: 'myoperator_' + fieldData['operator'], name: 'operator' };
items[2] = { xtype: fieldData['widget'], name: 'value' }
fieldSet.items = items;
return fieldSet;
}
})
This is a simple and contrived example, but it should (after you fill in the blanks, such as missing requires and the custom operator widgets) render a form based on the JSON data.
(I personally use this approach - with a great deal more sophistication that I can show in a simple example - to generate dynamic forms based on server-supplied form descriptions)

CSV Parser through angularJS

I am building a CSV file parser through node and Angular . so basically a user upload a csv file , on my server side which is node the csv file is traversed and parsed using node-csv
. This works fine and it returns me an array of object based on csv file given as input , Now on angular end I need to display two table one is csv file data itself and another is cross tabulation analysis. I am facing problem while rendering data, so for a table like
I am getting parse responce as
For cross tabulation we need data in a tabular form as
I have a object array which I need to manipulate in best possible way so as to make easily render on html page . I am not getting a way how to do calculation on data I get so as to store cross tabulation result .Any idea on how should I approach .
data json is :
[{"Sample #":"1","Gender":"Female","Handedness;":"Right-handed;"},{"Sample #":"2","Gender":"Male","Handedness;":"Left-handed;"},{"Sample #":"3","Gender":"Female","Handedness;":"Right-handed;"},{"Sample #":"4","Gender":"Male","Handedness;":"Right-handed;"},{"Sample #":"5","Gender":"Male","Handedness;":"Left-handed;"},{"Sample #":"6","Gender":"Male","Handedness;":"Right-handed;"},{"Sample #":"7","Gender":"Female","Handedness;":"Right-handed;"},{"Sample #":"8","Gender":"Female","Handedness;":"Left-handed;"},{"Sample #":"9","Gender":"Male","Handedness;":"Right-handed;"},{"Sample #":";"}
There are many ways you can do this and since you have not been very specific on the usage, I will go with the simplest one.
Assuming you have an object structure such as this:
[
{gender: 'female', handdness: 'lefthanded', id: 1},
{gender: 'male', handdness: 'lefthanded', id: 2},
{gender: 'female', handdness: 'righthanded', id: 3},
{gender: 'female', handdness: 'lefthanded', id: 4},
{gender: 'female', handdness: 'righthanded', id: 5}
]
and in your controller you have exposed this with something like:
$scope.members = [the above array of objects];
and you want to display the total of female members of this object, you could filter this in your html
{{(members | filter:{gender:'female'}).length}}
Now, if you are going to make this a table it will obviously make some ugly and unreadable html so especially if you are going to repeat using this, it would be a good case for making a directive and repeat it anywhere, with the prerequisite of providing a scope object named tabData (or whatever you wish) in your parent scope
.directive('tabbed', function () {
return {
restrict: 'E',
template: '<table><tr><td>{{(tabData | filter:{gender:"female"}).length}}</td></tr><td>{{(tabData | filter:{handedness:"lefthanded"}).length}}</td></table>'
}
});
You would use this in your html like so:
<tabbed></tabbed>
And there are ofcourse many ways to improve this as you wish.
This is more of a general data structure/JS question than Angular related.
Functional helpers from Lo-dash come in very handy here:
_(data) // Create a chainable object from the data to execute functions with
.groupBy('Gender') // Group the data by its `Gender` attribute
// map these groups, using `mapValues` so the named `Gender` keys persist
.mapValues(function(gender) {
// Create named count objects for all handednesses
var counts = _.countBy(gender, 'Handedness');
// Calculate the total of all handednesses by summing
// all the values of this named object
counts.Total = _(counts)
.values()
.reduce(function(sum, num) { return sum + num });
// Return this named count object -- this is what each gender will map to
return counts;
}).value(); // get the value of the chain
No need to worry about for-loops or anything of the sort, and this code also works without any changes for more than two genders (even for more than two handednesses - think of the aliens and the ambidextrous). If you aren't sure exactly what's happening, it should be easy enough to pick apart the single steps and their result values of this code example.
Calculating the total row for all genders will work in a similar manner.

Iterating through couchbase keys without a view

In couchbase, I was wondering if there was a way - WITHOUT using a view - to iterate through database keys. The admin interface appears to do this, but maybe its doing something special. What I'd like to is make a call like this to retrieve an array of keys:
$result = $cb->get("KEY_ALBERT", "KEY_FRED");
having the result be an array [KEY_ALEX, KEY_BOB, KEY_DOGBERT]
Again, I don't want to use a view unless there's no alternative. Doesn't look like its possible, but since the "view documents" in the admin appears to do this, I thought i'd double-check. I'm using the php interface if that matters.
Based on your comments, the only way is to create a simple view that emit only the id as par of the key:
function(doc, meta) {
emit( meta.id );
}
With this view you will be able to create query with the various options you need :
- pagination, range, ...
Note: you talk about the Administration Console, the console use an "internal view" that is similar to what I have written above (but not optimized)
I don't know about how couchbase admin works, but there are two options. First option is to store your docs as linked list, one doc have property (key) that points to another doc.
docs = [
{
id: "doc_C",
data: "somedata",
prev: "doc_B",
next: "doc_D"
},
{
id: "doc_D",
data: "somedata",
prev: "doc_C",
next: "doc_E"
}
]
The second approach is to use sequential id. You should have one doc that contain sequence and increment it on each add. It would be something like this:
docs = [
{
id: "doc_1",
data: "somedata"
},
{
id: "doc_2",
data: "somedata"
}
...
]
In this way you can do "range requests". To do this you form array of keys on server side:
[doc_1, doc_2 .... doc_N]and execute multiget query. Here is also a link to another example
The couchbase PHP sdk does support multiget requests. For a list of keys it will return an array of documents.
getMulti(array $ids, array $cas, int $flags) : array
http://www.couchbase.com/autodocs/couchbase-php-client-1.1.5/classes/Couchbase.html#method_getMulti

I can't manage to create 3rd level of dijit.Tree

I wanted to create a 3 level dijit.Tree, like that:
-root
|
--level1
|
--level2
I thought it would be really simple since there's a code snippet in this tutorial (example 1). But somehow I manage to fail.
This is my dojo code (variable names are in Polish, I hope it's not a problem):
modelRaportow = new dijit.tree.ForestStoreModel({
store: new dojo.data.ItemFileReadStore({
url: "logika/getJSON/getStatusRaportow.php"
}),
query: {typ: 'galaz'},
rootId: 'statusRaportuRoot',
rootLabel: 'Status raportu',
childrenAttrs: 'raporty'
});
drzewoRaportow = new dijit.Tree({
openOnClick: true,
model: modelRaportow,
showRoot: true,
persist: false
}, "target-status-raportow");
drzewoRaportow.startup();
This is my JSON returned by logika/getJSON/getStatusRaportow.php (again, names are in Polish):
{
"identifier":"id",
"label":"status",
"items": [
{"id":0,"status":"zaakceptowane","typ":"galaz"
"raporty":[{"_reference":1},{"_reference":2},{"_reference":3}]},
{"id":1,"data":"24-10-2011","wykonujacy":"cblajszczak","idKlienta":3,"status":"Raport0","typ":"lisc"},
{"id":2,"data":"24-10-2011","wykonujacy":"cblajszczak","idKlienta":1,"status":"Raport1","typ":"lisc"},
{"id":3,"data":"24-10-2011","wykonujacy":"cblajszczak","idKlienta":3,"status":"Raport2","typ":"lisc"},
{"id":4,"status":"odrzucone","typ":"galaz"
"raporty":[{"_reference":5},{"_reference":6},{"_reference":7}]},
{"id":5,"data":"24-10-2011","wykonujacy":"cblajszczak","idKlienta":1,"status":"Raport3","typ":"lisc"},
{"id":6,"data":"24-10-2011","wykonujacy":"cblajszczak","idKlienta":3,"status":"Raport4","typ":"lisc"},
{"id":7,"data":"24-10-2011","wykonujacy":"cblajszczak","idKlienta":3,"status":"Raport5","typ":"lisc"}
]}
And finally, this is what I'm getting: img - root node and lvl 1 nodes returned by query, no child nodes.
The question is - where is my mistake? Can anyone see it?
You have no comma between the typ and raporty value pair.
I have a partial answer: by stepping through the code in a similar situation, I've discovered that it expects childrenAttrs to be an array, so it should be:
childrenAttrs: ['raporty']
but I still cannot get the third level to appear in my case.