Develop Reference

Retain the selection in previous page when moved to next in ExtJS Combo box

I have the ExtJs form combo which shows the values in the dropdown as checkbox and the value to select. I have used the pagination to list all the values with no of pages. I need the selected value to be retained in the current page even when we move to next or previous page and comes back to the same page(without selecting any thing in prev, next pages).
Code:
Ext.create('Ext.form.ComboBox', {
id: 'ageComboPickerReport',
name: 'ageComboPickerReport',
maxHeight: 150,
margin: '0 5 0 0',
width: 150,
emptyText: "Select tags",
listConfig: {
getInnerTpl: function (displayField) {
return '<div class="x-combo-list-item"><img src="" class="chkCombo-default-icon
chkCombo" /> {' + displayField + '}</div>';
},
autoEl: { 'q-name': 'rpt-age-criteria-list'
}, labelAlign: 'top',
pageSize: 25,
displayField: 'age', valueField: 'id', forceSelection: true, store: me.ageStore,
//Disable Typing and Open Combo
onFocus: function () {
if (!this.isExpanded) {
me.ageStore.load()
this.expand()
} this.getPicker().focus();
}
}),
Could any one tell me how to retain the selected value in the page when move to other page and comes back

I faced a very similar issue, in my case I had a grid with checkbox selection model, and I wanted to retain the selected rows during moving between pages. I am quite sure (although not 100%) that there is no built-in functionality for that in ExtJS. I can tell what I did, hope it helps, although you have to adopt it because it is not for ComboBox, but for Grid.
Since this is a paged store, not all of the records are loaded, only the ones that are currently on the displayed page. (I assume your store is remote because I see you call load on it.) So to achieve what you like, you need to:
keep track of the selected record ids to be able the reset selection on page,
keep track the items (records) themselves as well, since you will likely need them,
after a page is loaded and displayed, set the selection accordingly.
(This solution can have issues, so you need to be careful. Depending on the use case, it is possible for example that the user selects something, goes to another page and come back, but the previously selected row is no more available (it was deleted by someone else). You have to consider whether it affects you.)
The complete code is complicated and not general enough to share it, but I can outline the steps I did:
Set up two data entries in viewmodel to track the selected record ids and items (records):
data: {
multiSelection: {
ids: {},
items: [],
},
}
Add listeners to the grid's select and deselect events in the view:
listeners: {
select: 'onGridSelect',
deselect: 'onGridDeselect',
},
Create onGridSelect and onGridDeselect functions in the controller, and also add a isDataChanged variable to the controller to indicate whether the store was changed (it is changed on each paging). It is important because I will programatically change the selection, and I don't want my listeners to be executed in this case, only when the user interacts. Like this:
isDataChanged: false,
onGridSelect: function(selModel, record, index, eOpts) {
if (isDataChanged) {
return;
}
const viewModel = this.getViewModel(),
multiSelection = viewModel.get('multiSelection');
multiSelection.ids[record.getId()] = true;
Ext.Array.push(multiSelection.items, record);
},
onGridDeselect: function(selModel, record, index, eOpts) {
if (isDataChanged) {
return;
}
const viewModel = this.getViewModel(),
multiSelection = viewModel.get('multiSelection');
delete multiSelection.ids[record.getId()];
Ext.Array.remove(multiSelection.items, record);
},
Finally, add a listeners to the store to detect changes, this will be called every time the user moves between pages. This is a little tricky, because I need to access the grid from the store listeners which is not very ExtJS like, but I had to (store needs to be the grid's store:
store.on('datachanged', function(store, eOpts) {
// this part you have to figure out, my solution is way too specific
// for share
const grid = ...;
// this was important for me, if the store is really changed,
// deleted, added rows etc., I deleted the selection, but
// you can consider it
if (store.getUpdatedRecords().length > 0 ||
store.getRemovedRecords().length > 0 ||
store.getNewRecords().length > 0) {
// access the `viewmodel` and reset `multiSelection` data entries to
// default, I `return` here to skip the rest
return;
}
// disable listener
grid.getController().isDataChanged = true;
const selModel = grid.getSelectionModel(),
multiSelection = grid.getViewModel().get('multiSelection');
// deselect everything
selModel.deselectAll();
// get an array of the saved selection and find out, which
// record from the current page is in the saved multiSelection
const selected = [];
Ext.Array.each(grid.getStore().getRange(), function(record) {
if (multiSelection.ids[record.getId()]) {
Ext.Array.push(selected, record);
}
});
// apply selection to current page
selModel.select(selected);
// enable listener
grid.getController().isDataChanged = false;
}

Assigning selected rows as other grid datasource

I am working on setting up a scenario as following:
1) User is shown existing results on first grid
2) User can select multiple results and click an 'Edit' button which will extract the selected items from the first grid
3)Second grid will be populated with the rows the user has selected from the first grid and will allow them to make edits to the content
4)Pressing save will update the results and show the first grid with the rows updated
So far using drips and drabs of various forum threads (here and here), I have managed to accomplish the first two steps.
$("#editButton").kendoButton({
click: function () {
// extract selected results from the grid and send along with transition
var gridResults = $("#resultGrid").data("kendoGrid"); // sourceGrid
var gridConfig = $("#resultConfigGrid").data("kendoGrid"); // destinationGrid
gridResults.select().each(function () {
var dataItem = gridResults.dataItem($(this));
gridConfig.dataSource.add(dataItem);
});
gridConfig.refresh();
transitionToConfigGrid();
}
});
dataItem returns what i am expecting to see with regards to the selected item(s) - attached dataItem.png. I can see the gridConfig populating but with blank rows (gridBlankRows.png).
gridConfig setup:
$(document).ready(function () {
// build the custom column schema based on the number of lots - this can vary
var columnSchema = [];
columnSchema.push({ title: 'Date Time'});
for(var i = 0; i < $("#maxNumLots").data("value"); ++i)
{
columnSchema.push({
title: 'Lot ' + i,
columns: [{
title: 'Count'
}, {
title: 'Mean'
}, {
title: 'SD'
}]
});
}
columnSchema.push({ title: 'Comment'});
columnSchema.push({ title: 'Review Comment' });
// build the datasource with CU operations
var configDataSource = new kendo.data.DataSource({
transport: {
create: function(options) {},
update: function(options) {}
}
});
$("#resultConfigGrid").kendoGrid({
columns: columnSchema,
editable: true
});
});
I have run out of useful reference material to identify what I am doing wrong / what could be outstanding here. Any help/guidance would be greatly appreciated.
Furthermore, I will also need functionality to 'Add New' results. If possible I would like to use the same grid (with a blank datasource) in order to accomplish this. The user can then add rows to the second grid and save with similar functionality to the update functionality. So if there is any way to factor this into the response, I would appreciate it.

The following example...
http://dojo.telerik.com/EkiVO
...is a modified version of...
http://docs.telerik.com/kendo-ui/framework/datasource/crud#examples
A couple of notes:
it matters if you are adding plain objects to the second Grid's dataSource (gridConfig.dataSource.add(dataItem).toJSON();), or Kendo UI Model objects (gridConfig.dataSource.add(dataItem);). In the first case, you will need to pass back the updated values from Grid2 to Grid1, otherwise this will occur automatically;
there is no need to refresh() the second Grid after adding, removing or changing its data items
both Grid dataSources must be configured for CRUD operations, you can follow the CRUD documentation
the Grid does not persist its selection across rebinds, so if you want to preserve the selection in the first Grid after some values have been changed, use the approach described at Persist Row Selection

AngularJS + ag-grid: sticky/remembered selections with virtual paging/infinite scrolling

In an AngularJS application, I have an ag-grid that uses virtual paging/infinite scrolling to lazy-load rows from a dataset that is too large to show at once. I have turned on check-box selection in the first column, so that the user should be able to select individual rows for arbitrary application-specific actions.
The AngularJS application uses ui-router to control multiple views. So, building on the virtual-paging example with "sorting & filtering", with constructed data about Olympic winners, from the ag-grid documentation, I've further extended the code a bit. From index.html:
<body ng-controller="MainController" class="container">
<div ui-view="contents"></div>
</body>
and the following ui-router states:
myapp.config(function($stateProvider, $urlRouterProvider) {
$urlRouterProvider.otherwise("example.page1")
$stateProvider
.state('example', {
abstract: true,
views: {
contents: {
template: '<div ui-view="example"></div>'
}
}
})
.state('example.page1', {
url: '/page1',
views: {
example: {
templateUrl: 'page1.html'
}
}
})
.state('example.page2', {
url: '/page2',
views: {
example: {
template: 'Go back to the <a ui-sref="example.page1">example grid</a>.'
}
}
});
});
where page1.html looks like the following:
<div ng-controller="GridController">
<div ag-grid="gridOptions" class="ag-fresh" style="height: 250px;"></div>
</div>
<div>
<h3>Selected rows:</h3>
<ul class="list-inline">
<li ng-repeat="row in currentSelection track by row.id">
<a ng-click="remove(row)">
<div class="badge">#{{ row.id }}, {{ row.athlete }}</div>
</a>
</li>
</ul>
</div>
<p>Go to <a ui-sref="example.page2">the other page</a>.</p>
What I want to accomplish:
That selections made in the ag-grid is remembered (sticky) when scrolling a (virtual) page out of view and back again, so that a user can select multiple rows on separate pages.
That the remembered selections are available outside the grid, and support adding and removing selections (as intended by the ng-click="remove(row)" in page1.html, shown above).
That the selections should be remembered when switching from the view with the ag-grid to another one, and back again.
(Optional) That the selections are remembered for the user's session.
How can I accomplish this?

I've created a working example of this can be implemented.
First of all, we'll write a AngularJS service, selectionService to keep track of the selections:
function _emptyArray(array) {
while (array.length) {
array.pop();
}
}
function _updateSharedArray(target, source) {
_emptyArray(target);
_.each(source, function _addActivity(activity) {
target.push(activity);
});
}
myapp.factory('selectionService', function ($rootScope, $window) {
var _collections = {},
_storage = $window.sessionStorage,
_prefix = 'selectionService';
angular.element($window).on('storage', _updateOnStorageChange);
function _persistCollection(collection, data) {
_storage.setItem(_prefix + ':' + collection, angular.toJson(data));
}
function _loadCollection(collection) {
var item = _storage.getItem(_prefix + ':' + collection);
return item !== null ? angular.fromJson(item) : item;
}
function _updateOnStorageChange(event) {
var item = event.originalEvent.newValue;
var keyParts = event.originalEvent.key.split(':');
if (keyParts.length < 2 || keyParts[0] !== _prefix) {
return;
}
var collection = keyParts[1];
_updateSharedArray(_getCollection(collection), angular.fromJson(item));
_broadcastUpdate(collection);
}
function _broadcastUpdate(collection) {
$rootScope.$emit(_service.getUpdatedSignal(collection));
}
function _afterUpdate(collection, selected) {
_persistCollection(collection, selected);
_broadcastUpdate(collection);
}
function _getCollection(collection) {
if (!_.has(_collections, collection)) {
var data = _loadCollection(collection);
// Holds reference to a shared array. Only mutate, don't replace it.
_collections[collection] = data !== null ? data : [];
}
return _collections[collection];
}
function _add(item, path, collection) {
// Add `item` to `collection` where item will be identified by `path`.
// For example, path could be 'id', 'row_id', 'data.athlete_id',
// whatever fits the row data being added.
var selected = _getCollection(collection);
if (!_.any(selected, path, _.get(item, path))) {
selected.push(item);
}
_afterUpdate(collection, selected);
}
function _remove(item, path, collection) {
// Remove `item` from `collection`, where item is identified by `path`,
// just like in _add().
var selected = _getCollection(collection);
_.remove(selected, path, _.get(item, path));
_afterUpdate(collection, selected);
}
function _getUpdatedSignal(collection) {
return 'selectionService:updated:' + collection;
}
function _updateInGridSelections(gridApi, path, collection) {
var selectedInGrid = gridApi.getSelectedNodes(),
currentlySelected = _getCollection(collection),
gridPath = 'data.' + path;
_.each(selectedInGrid, function (node) {
if (!_.any(currentlySelected, path, _.get(node, gridPath))) {
// The following suppressEvents=true flag is ignored for now, but a
// fixing pull request is waiting at ag-grid GitHub.
gridApi.deselectNode(node, true);
}
});
var selectedIdsInGrid = _.pluck(selectedInGrid, gridPath),
currentlySelectedIds = _.pluck(currentlySelected, path),
missingIdsInGrid = _.difference(currentlySelectedIds, selectedIdsInGrid);
if (missingIdsInGrid.length > 0) {
// We're trying to avoid the following loop, since it seems horrible to
// have to loop through all the nodes only to select some. I wish there
// was a way to select nodes/rows based on an id.
var i;
gridApi.forEachNode(function (node) {
i = _.indexOf(missingIdsInGrid, _.get(node, gridPath));
if (i >= 0) {
// multi=true, suppressEvents=true:
gridApi.selectNode(node, true, true);
missingIdsInGrid.splice(i, 1); // Reduce haystack.
if (!missingIdsInGrid.length) {
// I'd love for `forEachNode` to support breaking the loop here.
}
}
});
}
}
var _service = {
getCollection: _getCollection,
add: _add,
remove: _remove,
getUpdatedSignal: _getUpdatedSignal,
updateInGridSelections: _updateInGridSelections
};
return _service;
});
The selectionService service allows adding and removing arbitrary objects to separate collections, identified by collection, a name you find suitable. This way the same service can be used for remembering selections in multiple ag-grid instances. Each object will be identified using a path parameter. The path is used to retrieve the unique identifier using lodash's get function.
Furthermore, the service uses sessionStorage to persist the selections during the user's whole tab/browser session. This might be overkill; we could have just relied on the service to keep track of the selections since it will only get instantiated once. This can of course be modified to your needs.
Then there were the changes that had to be done to the GridController. First of all the columnDefs entry for the first column had to be changed slightly
var columnDefs = [
{
headerName: "#",
width: 60,
field: 'id', // <-- Now we use a generated row ID.
checkboxSelection: true,
suppressSorting: true,
suppressMenu: true
}, …
where the new, generated row ID is generated once the data has been retrieved from the remote server
// Add row ids.
for (var i = 0; i < allOfTheData.length; i++) {
var item = allOfTheData[i];
item.id = 'm' + i;
}
(The 'm' in the ID was included just to make sure I didn't confused that ID with other IDs used by ag-grid.)
Next, the necessary changes to gridOptions were to add
{
…,
onRowSelected: rowSelected,
onRowDeselected: rowDeselected,
onBeforeFilterChanged: clearSelections,
onBeforeSortChanged: clearSelections,
…
}
Were the different handlers are quite straight forward, communicating with the selectionService
function rowSelected(event) {
selectionService.add(event.node.data, 'id', 'page-1');
}
function rowDeselected(event) {
selectionService.remove(event.node.data, 'id', 'page-1');
}
function clearSelections(event) {
$scope.gridOptions.api.deselectAll();
}
Now, the GridController needs to handle updates signalled by the selectionService too
$scope.$on('$destroy',
$rootScope.$on(selectionService.getUpdatedSignal('page-1'),
updateSelections));
and
function updateSelections() {
selectionService.updateInGridSelections($scope.gridOptions.api, 'id', 'page-1');
}
calls selectionService.updateInGridSelections which will update the in-grid selections of the grid in question. That was the most cumbersome function to write. For example, if a selection has been added externally (outside the grid), then we'll have to perform a forEachNode run, even if we know all the necessary nodes have already been selected in-grid; there's no way to exit that loop early.
Finally, another crux was to clear and reapply the selections before and after, respectively, when the filters or sort orders are changed, or when new data is retrieved from the server (which is only simulated in the demo). The solution was to include a call to updateSelections after the params.successCallback inside the getRows handler
params.successCallback(rowsThisPage, lastRow);
updateSelections();
Now, the most puzzling findings during the implementation of this solution was that the ag-grid API grid options onAfterFilterChanged and onAfterSortChanged couldn't be used for reapplying the selections because they trigger before the (remote) data has finished loading.

Kendo multi-select with tab key selection

I am trying to implement a feature to select an item in kendo's multi-select control with server filtering. when user presses tab on the selected item. Here is my code of kepdown event:
if (e.keyCode === 9) {
var selectedItem = multiSelect.current();
if (selectedItem) {
var selectedIndex = selectedItem.data("idx");
if (selectedIndex >= 0) {
var currentValue = multiSelect.value().slice();
var dataitems = multiSelect.dataSource.view();
var selectedDataItem = dataitems[selectedIndex];
multiSelect.dataSource.filter({});
currentValue.push(selectedDataItem.relatedId);
multiSelect.value(currentValue);
multiSelect.trigger("change");
}
}
}
But it works fine as long as I am searching in same data view i.e. lets say I select two values starting with Cloud and then I select a value starting with App then kendo will remove previous two values starting with Cloud and control will contain just one value selected at the last.
I debugged kendo's code that the issue in function _index of kendo because it finds value in dataSource.view
I have recreated the issue at http://dojo.telerik.com/OtAvi

Your code is not working because you have serverFiltering set to true in the dataSource:
dataSource: {
type: "odata",
serverFiltering: true,
transport: {
read: {
url: "http://demos.telerik.com/kendo-ui/service/Northwind.svc/Products",
}
}
},
Since the data is being filtered on the server, the call multiSelect.dataSource.filter({}); is only clearing the already filtered data. With that said, when you call multiSelect.value(currentValue);, only the values from the currently filtered dataSource can be selected. This is causing the selection to only hold items from the current dataView.
Unless you have a strong reason not to, your easiest fix is to set serverFiltering set to false.

ExtJS Change Event Listener failing to fire

I was asked to post this as a question on StackOverflow by http://twitter.com/jonathanjulian which was then retweeted by several other people. I already have an ugly solution, but am posting the original problem as requested.
So here's the back story. We have a massive database application that uses ExtJS exclusively for the client side view. We are using a GridPanel (Ext.grid.GridPanel) for the row view loaded from a remote store.
In each of our interfaces, we also have a FormPanel (Ext.form.FormPanel) displaying a form that allows a user to create or edit records from the GridPanel. The GridPanel columns are bound to the FormPanel form elements so that when a record is selected in the GridPanel, all of the values are populated in the form.
On each form, we have an input field for the table row ID (Primary Key) that is defined as such:
var editFormFields = [
{
fieldLabel: 'ID',
id: 'id_field',
name: 'id',
width: 100,
readOnly: true, // the user cannot change the ID, ever.
monitorValid: true
} /* other fields removed */
];
So, that is all fine and good. This works on all of our applications. When building a new interface, a requirement was made that we needed to use a third-party file storage API that provides an interface in the form of a small webpage that is loaded in an IFrame.
I placed the IFrame code inside of the html parameter of the FormPanel:
var editForm = new Ext.form.FormPanel({
html: '<div style="width:400px;"><iframe id="upload_iframe" src="no_upload.html" width="98%" height="300"></iframe></div>',
/* bunch of other parameters stripped for brevity */
});
So, whenever a user selects a record, I need to change the src attribute of the IFrame to the API URL of the service we are using. Something along the lines of http://uploadsite.com/upload?appname=whatever&id={$id_of_record_selected}
I initially went in to the id field (pasted above) and added a change listener.
var editFormFields = [
{
fieldLabel: 'ID',
id: 'id_field',
name: 'id',
width: 100,
readOnly: true, // the user cannot change the ID, ever.
monitorValid: true,
listeners: {
change: function(f,new_val) {
alert(new_val);
}
}
} /* other fields removed */
];
Nice and simple, except that it only worked when the user was focused on that form element. The rest of the time it failed to fire at all.
Frustrated that I was past a deadline and just needed it to work, I quickly implemented a decaying poller that checks the value. It's a horrible, ugly hack. But it works as expected.
I will paste my ugly dirty hack in an answer to this question.

"The GridPanel columns are bound to
the FormPanel form elements so that
when a record is selected in the
GridPanel, all of the values are
populated in the form."
As I understand it from the quote above, the rowclick event is what actually triggers the change to your form in the first place. To avoid polling, this could be the place to listen, and eventually raise to your custom change event.

Here is the ugly hack that I did to accomplish this problem:
var current_id_value = '';
var check_changes = function(offset) {
offset = offset || 100;
var id_value = document.getElementById('id_field').value || '';
if ( id_value && ( id_value != current_id_value ) ) {
current_id_value = id_value;
change_iframe(id_value);
} else {
offset = offset + 50;
if ( offset > 2500 ) {
offset = 2500;
}
setTimeout(function() { check_changes(offset); }, offset);
}
};
var change_iframe = function(id_value) {
if ( id_value ) {
document.getElementById('upload_iframe').src = 'http://api/upload.php?id=' + id_value;
} else {
document.getElementById('upload_iframe').src = 'no_upload.html';
}
setTimeout(function() { check_changes(100); }, 1500);
};
It's not pretty, but it works. All of the bosses are happy.

If you took a moment to read the source, you would see that the Ext.form.Field class only fires that change event in the onBlur function