dgrid inside ContentPane - Scroll error - dojo

Question

I have a problem with dgrid.... I have an AccordionContainer, and in each ContentPane of it,
I place a dgrid. The problems with the dgrid are:
1- Error with scroll: when scrolling down, in certain moment the scroll "skips" and jumps into the end and there's no way to scroll up and show the first records.
(I have seen in Firebug the error TypeError: grid._rows is null when the scroll fails).
2- Trying to change a value: sounds like no dgrid-datachange event is emitted,
no way to capture the event after editing a value.
I think these errors has to do with having dgrid inside layouts (dgrid inside ContentPane, inside AccordionContainer). I also included the DijitRegistry extension but even with this extensions I can't get
rid of this errors.
I have prepared this fiddle which reproduces the errors:
https://jsfiddle.net/9ax3q9jw/5/
Code:
var grid = new (declare([OnDemandGrid, DijitRegistry,Selection, Selector, Editor]))({
collection: tsStore,
selectionMode: 'none',
columns:
[
{id: 'timestamp', label:'Timestamp', formatter: function (value,rowIndex) {
return value[0];
}},
{id: 'value', label: 'Value',
get: function(value){
return value[1];
},
editor: "dijit/form/TextBox"
}
],
showHeader: true
});
grid.startup();
grid.on('dgrid-datachange',function(event){
alert('Change!');
console.log('Change: ' + JSON.stringify(event));
});
//Add Grid and TextArea to AccordionContainer.
var cp = new ContentPane({
title: tsStore.name,
content: grid
},"accordionContainer");
Any help will be appreciated,
Thanks,
Angel.

Answer 1

There are a couple of issues with this example that may be causing you problems.
Data
The store used in the fiddle is being created with an array of arrays, but stores are intended to work with arrays of objects. This is the root of the scrolling issue you're seeing. One property in each object should uniquely identify that object (the 'id' field). Without entry IDs, the grid can't properly keep track of the entries in your data set. The data array can easily be converted to an object array with each entry having timestamp and value properties, and the store can use timestamp as its ID property (the property it uses to uniquely identify each record).
var records = [];
var data = _globalData[0].data;
var item;
for (var i = 0; i < data.length; i++) {
item = data[i];
records.push({
timestamp: item[0],
value: item[1]
});
}
var tsStore = new declare([Memory, Trackable])({
data: records,
idProperty: 'timestamp',
name: 'Temperature'
});
_t._createTimeSeriesGrids(tsStore);
Setting up the store this way also allows the grid column definitions to be simplified. Using field names instead of IDs will allow the grid to call formatter functions with the corresponding field value for each row object.
columns: [{
field: 'timestamp',
label: 'Timestamp',
formatter: function (value) {
return value;
}
}, {
field: 'value',
label: 'Value',
formatter: function (value) {
return value;
},
editor: "dijit/form/TextBox"
}],
Loading
The fiddle is using declarative widgets and Dojo's automatic parsing functionality to build the page. In this situation the loader callback does not wait for the parser to complete before executing, so the widgets may not have been instantiated when the callback runs.
There are two ways to handle this: dojo/ready or explicit use of the parser.
parseOnLoad: true,
deps: [
...
dojo/ready,
dojo/domReady!
],
callback: function (..., ready) {
ready(function () {
var _t = this;
var _globalData = [];
...
});
}
or
parseOnLoad: false,
deps: [
...
dojo/parser,
dojo/domReady!
],
callback: function (..., parser) {
parser.parse().then(function () {
var _t = this;
var _globalData = [];
...
});
}
Layout
When adding widgets to containers, use Dijit's methods, like addChild and set('content', ...). These typically perform actions other than just adding a widget to the DOM, like starting up child widgets.
var cp = new ContentPane({
title: tsStore.name,
content: grid
});
registry.byId('accordionContainer').addChild(cp);
instead of
var cp = new ContentPane({
title: tsStore.name,
content: grid
}, "accordionContainer");
In the example code a ContentPane isn't even needed since the dgrid inherits from DijitRegistry -- it can be added directly as a child of the AccordionContainer.
This will also call the grid's startup method, so the explicit call in the code isn't needed.
registry.byId('accordionContainer').addChild(grid);
It also often necessary to re-layout the grid's container once the grid has been initially rendered to ensure it's properly sized.
var handle = grid.on('dgrid-refresh-complete', function () {
registry.byId('accordionContainer').resize();
// only need to do this the first time
handle.remove();
});