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Add QR code using external javascript file within Sencha framework

We are trying to add functionality to an old system. Our clients use scanners, so it would be ideal if we could add a QR code on screen for them to scan. I found a small open source javascript library that displays QR codes. I wanted to use that, but I am pulling the URL from the database, putting it into a Store, and then populating a link on screen. So, I have the following:
this.searchForm = {
frame: true,
xtype: 'form',
layout: 'form',
labelWidth: 150,
items: [{
xtype: 'component',
fieldLabel: 'Wireless App',
tpl: '<div id="qrcode" style="width:100px; height:100px;"></div>{Url}',
data: { Url: '' },
ref: '../../WirelessAppLabel'
}, {
xtype: 'label',
ref:'../../StatusLabel'
}]
};
lookupRF: function(search) {
this.createRFLookup();
this.lookupRFWindow.show();
this.WirelessAppStore = WirelessAppUrl.getInstance().createStore();
PM.Retriever.retrieve([this.WirelessAppStore], {
callback: function (response, success) {
if (success) {
this.WMSAppUrl = this.WirelessAppStore.data.items[0].data.Url;
this.lookupRFWindow.WirelessAppLabel.update({ Url: this.WMSAppUrl });
new QRCode(document.getElementById("qrcode"), this.WMSAppUrl);
}
},
scope: this
});
}
where PM is a namespace we created internally. (These two functions are not in the same file, but one references the other). But, I keep getting errors saying QRCode is not defined. I tried loading it using Ext.Loader.load() and also just adding a reference to the script in index.html, but neither option worked. Any suggestions?
Here is the link to the QR Code javascript we are attempting to utilize: https://davidshimjs.github.io/qrcodejs/

I found a much easier approach. Rather than try to do everything in Javascript, it is already hitting the server to pull from the database, so I added a QR Code generator that created a Bitmap server side, which converts it into a Base64String. So, now my code looks like this:
this.searchForm = {
frame: true,
xtype: 'form',
layout: 'form',
labelWidth: 150,
items: [{
xtype: 'component',
fieldLabel: 'Wireless App',
tpl: '{Url}<br/><img src="data:image/jpeg;base64, {Image}" style="width:100px;height:100px;" />',
data: {
Url: '',
Image: ''
},
ref: '../../WirelessAppLabel'
}, {
xtype: 'label',
ref:'../../StatusLabel'
}]
};
lookupRF: function(search) {
this.createRFLookup();
this.lookupRFWindow.show();
this.WirelessAppStore = WirelessAppUrl.getInstance().createStore();
PM.Retriever.retrieve([this.WirelessAppStore], {
callback: function (response, success) {
if (success) {
this.WMSAppUrl = this.WirelessAppStore.data.items[0].data.Url;
this.WMSAppImage = this.WirelessAppStore.data.items[0].data.QRCode;
this.lookupRFWindow.WirelessAppLabel.update({
Url: this.WMSAppUrl,
Image: this.WMSAppImage
});
}
},
scope: this
});
And then to actually create the QRCode, I used this open source package: https://github.com/codebude/QRCoder
Not exactly the solution that was asked for, but it works really well.

ExtJS Grid - how do I reference a store by id in my view

I am trying to reference a store in my app for the purpose of adding a paging tool bar at the bottom of my gird. In most examples I have studied the store is referenced by variable, ex: store: someStore. However, by I have build my app a little differently and did create a reference variable to the store. I have
tried assigning an id but this did not work.
Here is what I have:
In my view Grid.js:
Ext.define('myApp.view.user.Grid', {
extend: 'Ext.grid.Panel',
viewModel: {
type: 'user-grid'
},
bind: {
store: '{users}',
},
columns: {...},
//my paging tool bar
dockedItems: [{
xtype: 'pagingtoolbar',
dock: 'bottom',
store: 'girdStore'
//store: {users} -> did not work
}],
...
});
In my view model GridModel.js:
Ext.define('myApp.view.user.GridModel', {
extend: 'Ext.app.ViewModel',
requires: [
'myApp.model.User'
],
stores: {
users: {
model: 'myApp.model.User',
storeId: 'gridStore',
autoLoad: true
}
},
formulas: {...}
});
When I try to reference the {users} store by id 'gridStore' I get this error:
Uncaught TypeError: Cannot read property 'on' of undefined
What is the best way to proceed without completely refactoring my model?

When you have a reference to your grid, you could get the store by calling the getStore function. See the ExtJs 6.2.1 documentation.
var grid; // reference to your grid
var store = grid.getStore();
You can create the store in initComponent and then attach it to the dockedItems, so both will share the same store.
initComponent: function () {
var store = Ext.create('Ext.data.Store', {
model: 'myApp.model.User',
storeId: 'gridStore',
autoLoad: true
});
this.store = store;
this.dockedItems = [{
xtype: 'pagingtoolbar',
dock: 'bottom',
store:store
}];
this.callParent(arguments);
}
The initComponent is called once when a new instance of the class is created, see the description in the documentation.
...It is intended to be implemented by each subclass of
Ext.Component to provide any needed constructor logic. The
initComponent method of the class being created is called first, with
each initComponent method up the hierarchy to Ext.Component being
called thereafter. This makes it easy to implement and, if needed,
override the constructor logic of the Component at any step in the
hierarchy. The initComponent method must contain a call to callParent
in order to ensure that the parent class' initComponent method is also
called...
The view with the initComponent function.
Ext.define('myApp.view.user.Grid', {
extend: 'Ext.grid.Panel',
viewModel: {
type: 'user-grid'
},
initComponent: function () {
var store = Ext.create('Ext.data.Store', {
model: 'myApp.model.User',
storeId: 'gridStore',
autoLoad: true
});
this.store = store;
this.dockedItems = [{
xtype: 'pagingtoolbar',
dock: 'bottom',
store: store
}];
this.callParent(arguments);
},
columns: {...},
...
});

Getting Object Properties From External js File

I'm using a jquery script called jTable (www.jtable.org) to implement dynamic tables in my web application. In order to include a table on a particular page, you must include the following code to declare its properties:
<script type="text/javascript">
$(document).ready(function () {
$('#MyTableContainer').jtable({
//General options comes here
actions: {
//Action definitions comes here
},
fields: {
//Field definitions comes here
}
});
});
</script>
An example of what might go into the fields property:
fields: {
StudentId: {
key: true,
create: false,
edit: false,
list: false
},
Name: {
title: 'Name',
width: '23%'
},
EmailAddress: {
title: 'Email address',
list: false
},
Password: {
title: 'User Password',
type: 'password',
list: false
},
Gender: {
title: 'Gender',
width: '13%',
options: { 'M': 'Male', 'F': 'Female' }
},
BirthDate: {
title: 'Birth date',
width: '15%',
type: 'date',
displayFormat: 'yy-mm-dd'
}
}
The problem is I use the same table (or very similar tables) throughout my web application. I would like to be able to implement a way to store the fields in an external .js file and then refer to it on each page, thus avoiding copying and pasting. On some pages, I may only include some of the above fields (ex. I may want to exclude Password and EmailAddress) or make slight variations to the fields when I load them (ie. use a different displayFormat (for BirthDate) than the default in the external .js file on a particular page.
Thanks!

You can do this in several ways. Here's a simple one:
main.js
//should be modularized/namespaced
var defaultStudentTableFieldsCfg = {
...
};
other-file.js
$(function () {
var tableFieldsCfg = $.extend({}, defaultStudentTableFieldsCfg);
//define new column
tableFieldsCfg.someNewCol = {
//...
};
//remove some column
delete tableFieldsCfg.Password;
//override config
tableFieldsCfg.Gender.title = 'GENDER';
//it would be better not to hard-code #MyTableContainer here
$('#MyTableContainer').jtable({ fields: tableFieldsCfg });
});

You could create functions that you put in external JS files. Then those functions could return the JSON objects needed to construct your jTable.

The problem is the fact that you have a JSON object and that can not be just referenced in a JavaScript file. If you want to load the file, you would need to use something like getJSON and than use that with jQuery.
function createTable(fields) {
$('#MyTableContainer').jtable({
//General options comes here
actions: {
//Action definitions comes here
},
fields: fields
});
}
$(function(){
$.getJSON("YourFields.json", createTable);
});
Now what you are trying to do is reference a global variable.
Place the file before and reference the global variable.
<script type="text/javascript" src="YourFields.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$('#MyTableContainer').jtable({
actions: {
},
fields: fields
});
});
</script>
The YourFields.js file should look more like
if (!window.appDefaults) {
window.appDefaults = {}
}
window.appDefaults.fields = {
StudentId: {
key: true,
...
};

Dynamically loading a non-class in ExtJS 4

I have two classes in ExtJS 4 (a grid and a form) with correlated properties (column and field definitions).
I want to create a common definition file for them and dynamically load it:
# app/common/Columns.js
Ext.ns('myapp.common');
myapp.common.Columns =
[
{
text: 'Name',
dataIndex: 'name',
},
{
text: 'Email',
dataIndex: 'email',
}
];
# app/view/Grid.js
Ext.define
(
'myapp.view.Grid',
{
extend: 'Ext.grid.Panel',
columns: myapp.common.Columns
}
);
# app/view/Form.js
Ext.define
(
'myapp.view.Form',
{
extend: 'Ext.form.Panel',
items: myapp.common.Columns.map
(
function(v)
{
return {
name: v.dataIndex,
fieldLabel: v.text,
};
}
);
}
);
As you can see, app.common.Columns is not a class.
I know I can convert it into a class and override the form's and the grid's constructors to use it, but I'd like to keep it simple.
Do I need to add a <script> tag for app/common/Columns.js manually or there is a way to load it dynamically?

I don't think you can load file dynamically using ExtJs loader without having a class defined there. Their loader is very picky about exactly matching class name to file name. I just tried your sample - it doesn't seems to be working.

Defining items of an object inside the initialize function

I am trying to create items inside a component as it gets initialized, with a function.
Consider the following:
Ext.define('mobi.form.Login',{
extend:'Ext.form.Panel',
config:{
items: [{
xtype: 'textfield',
name: 'Name',
label: 'Name'
}]
});
Ext.application({
viewport: {
layout:'fit'
},
launch: function(){
Ext.Viewport.add(Ext.create('mobi.form.Login'));
}
})
I am trying to get The mobi.form.login to generate its config from a function that runs on initialize ( or whatever I can use to over write the config I specify ).
I know Sencha touch 2 has the constructor, and initialize function, but both of them seem to have arguments=[] ( eg an empty array )
This is more or less how it would look if I was doing it in ExtJS 4.x:
Ext.define('mobi.form.Login',{
extend:'Ext.form.Panel',
initComponent:function(config){
config=Ext.apply({}.config,{});//make sure config exists
config.items= [{
xtype: 'textfield',
name: 'Name',
label: 'Name'
}]
Ext.apply(this, config);
this.callParent(arguments);
}
});

If you ever wanted to do this, you could use constructor or initialize.
Constructor you would use for synchronous logic which will be fast and you want to happen before the component is initialized. You can access the configuration through the constructors first argument:
Ext.define('MyComponent', {
extend: 'Ext.Component',
constructor: function(config) {
console.log(config);
this.callParent([config]);
}
});
Ext.application({
launch: function(){
Ext.create('MyComponent', { test: 1 })
// Will log out:
// {
// test: 1
// }
}
});
Remember you will always need to callParent with the config/arguments within constructor.
In any other situation, you should use initialize which is called after all the config's have been... initialized. :) We use this a lot internally for adding listeners.
initialize: function() {
this.on({
...
});
}

you don't need to call initialize manually it is already done by constructor and when calling this function you can access items data using this.items and create panel items there
Ext.define('mobi.form.Login',{
extend:'Ext.form.Panel',
config: {
items: []
},
initialize : function()
{
this.items = [Ext.create({
xtype: 'textfield',
name: 'Name',
label: 'Name'
})];
this.callParent();
}
});
Ext.application({
viewport: {
layout:'fit'
},
launch: function(){
Ext.Viewport.add(Ext.create('mobi.form.Login'));
}
})

Use the following:
Ext.apply(this, {
items: [
....
]
});

Have you tried something similar to this? I'm just passing a config object to Ext.create, though I can't test it right now. See http://docs.sencha.com/touch/1-1/#!/api/Ext-method-create
Ext.Viewport.add(Ext.create(
{
xtype: 'mobi.form.Login',
items: [ /*A list of items*/ ]
}
));
You could stick this snippet in its own function as well, one that takes in items as a parameter. Hope this solves your problem!