Develop Reference

Django Modelmultiplechoicefield Checkboxselectmultiple Problem Getting Selected Checkbox

I have been working all day to try and get the selected values on one set of checkboxes on my Django form and copy the selected ones only to an identical checkbox on my form. If a user clicks on a checkbox in form.author defined below, I want the same identical checkbox to automatically be checked on form.favorite_author defined below.
I've tried a JQuery approach as documented here...Copy Selected Checkbox Value From One Checkbox To Another Immediately Using JQUERY but no luck so far. I've recently begun exploring an avenue with the Modelmultiplechoicefield and the checkboxselectmultiple parameters within the form itself. From what I can tell, when I am using JQuery and trying to check a box on the form, the value is coming back as undefined which is most likely why it is not propagating the checkbox selection to the other checkbox.
Here is my form....
class ManagerUpdateNewAssociateForm(forms.ModelForm):
class Meta:
model = Library
self.fields['author'] = forms.ModelMultipleChoiceField(
widget=forms.CheckboxSelectMultiple(),
queryset=Books.objects.all()
self.fields['favorite_author'] = forms.ModelMultipleChoiceField(
widget=forms.CheckboxSelectMultiple(),
queryset=Books.objects.all()
My HTML...
<div class="spacer83">
{{ form.author }}
</div>
<div class="spacer83">
{{ form.favorite_author }}
</div>
When I tried to trace JQuery, it told me the checkbox selections are undefined. I did read a bit about how Modelmultiplechoicefield, since it uses a queryset it doesn't show the selections, but I can't figure out how to get it to.
Thanks in advance for any thoughts.

In combination with the other issue included in this one, I went back to the JQuery route and explored further. From what I can tell, I was not able to use the class for the input because of the way the HTML for Django forms is generated in this use case. I ultimately was able to leverage the input name and then used the code below to interrogate the checkboxes accordingly:
$(document).ready(function() {
$("[name=author]").change(function() {
let selectedValA = $(this).val();
let isAChecked = $(this).prop("checked");
$(`[name=favorite_author][value="${selectedValA}"]`).prop("checked", isAChecked);
});
});
});

Jquery DataTable keeps going back to first page when changing the checked status of checkboxes in other pages with javascript

I have the following code
$('input[name="select-all"]').click(function() {
//channel-data is initialised as DataTable
$('#channel-table').find('input[name="batch-select"]:checked').each(function () {
$(this).prop("checked",true);
});
});
whenever I click the select all button in any page other than 1st The datatable keeps reverting back to the first page.
I think it happens because of redraw due to change in checkboxes property.Any work around this?

Yes, probably - but have not seen any reason for test your hypothesis :) When dealing with dataTables, always go through the API! There is a neat every() method you can use to cycle through all rows and update a checkbox as checked. Here is an example, have tried to reproduce your setup with a "select all" button and checkboxes :
$('input[name="select-all"]').click(function() {
table.rows().every( function ( rowIdx, tableLoop, rowLoop ) {
var $tr = this.nodes().to$()
$tr.find('input[name="batch-select"]').prop('checked', true)
})
})
demo -> http://jsfiddle.net/u9Lq56v1/
does not change page
does actually update checkboxes also on hidden pages (that would the code in OP fail as well)

Event backgrid:rendered does not work - Backgrid.js

I try to use Backgrid.js. I have some grid (I just take server-mode example).
This library successfully built a grid for me. But I want map some cells to their equivalent. For example, I have "region_id" column. I want map region_id -> region_name. To complete this task, I subscribed to the event backgrid:rendered.
var grid = new Backgrid.Grid({
/////
collection: issues
});
grid.on('backgrid:rendered', function(g) {
$('tr').each(function (i, row) {
var $row = $(row);
console.log("Q");
});
});
But I get a fail. There is no iterating over rows of my table. But these rows exist in table. What is the problem?

Verify that both of the following is true:
you make a call to grid.render() method
issues variable refers to non-empty collection at the time of rendering

Unfortunately Backgrid fires the rendered event before the header, footer and the table itself are actually on the screen.
So when your event gets triggered there are no rows in DOM yet.
I solved my problem by calling my code after the
grid.render().$el
statement. After this table should be in DOM. At least header row was and that was all I needed.
I am stuck with old version of Backgrid 0.2.6. So bare in mind that my answer is from that perspective.

How to update ZK Grid values from jQuery

I have three Tabs and in each tab, I have a Grid.
The data for each Grid is coming from a database, so I am using rowRenderer to populate the Grids. The following code is common for all three Grids:
<grid id="myGrid1" width="950px" sizedByContent="true" rowRenderer="com.example.renderer.MyRowRenderer">
The rows are constructed from Doublebox objects. The data is populated successfully.
The Problem:
I need to handle multiple-cell editing on the client side. The editing is done via mouse-clicking on a particular cell and entering a value.
As example let's say that the user edits first cell on the first row and the value should be
propagated to all other cells on the same row and in all three Grids (so also the two Grids which the user currently does not see, because they are in tabpanes).
I am using jQuery to do this value propagation and it works OK.
I am passing the jQuery as follows:
doublebox.setWidgetListener(Events.ON_CHANGING, jQuerySelectors);
doublebox.setWidgetListener(Events.ON_CHANGE, jQuerySelectors);
This makes it possible to change the value in 1 cell and the change is instantly (visually) seen in all other cells filtered by jQuery selectors.
The problem is that the value is visually distributed to all the cells, but when I try to save the Grid data back to the database, the background values are the old ones.
I am assuming that ZK-Grid component is not aware that jQuery changed all the cell values. Nevertheless if I manually click on a cell that already has the NEW value (enter/leave/change focus) when I save the grid the NEW value is correct in that particular cell. Maybe that's a hint how can I resolve this.
Code of how I extract the Grid values:
Grid tGrid = (Grid) event.getTarget().getFellow("myGrid1");
ListModel model = tGrid.getModel();
MyCustomRow tRow = (MyCustomRow)model.getElementAt(i);
The model for my Grid is a List of MyCustomRow:
myGrid1.setModel(new ListModelList(List<MyCustomRow> populatedList));
I have a couple of assumptions, but whatever I have tried, hasn't worked. I have in mind that jQuery events and ZK-Events are different and probably isolated in different contexts. (Although I have tried to fire events from jQuery and so on..)
Do you have any suggestions? As a whole is my approach correct or there's another way to do this? Thanks for your time in advance!

Your problem is exactly what you are expecting.
Zk has it's own event system and do not care about your jq,
cos it's jq and zk don't observ the DOM.
The ways to solve your problem.
Use the "ZK-Way":
Simply listen at server-side and chage things there.
I am not sure if not selected Tabs
are updateable, but I am sure you could update the Grid
components on the select event of the Tab.
Fire an zk-event your self:
All you need to know, is written in the zk doc.
Basically, you collect your data at client side, send
an Event to the server via zAu.send() extract the
data from the json object at serverside and update your Grids
I would prefer the first one, cos it's less work and there should not be
a notable difference in traffic.

I post the solution we came up with:
This is the javascript attached to each Doublebox in the Z-Grid
//getting the value of the clicked cell
var currVal = jq(this).val();
//getting the next cell (on the right of the clicked cell)
objCells = jq(this).parents('td').next().find('.z-doublebox');
// if there's a next cell (returned array has length) - set the value and
// fire ZK onChange Event
if (objCells.length) {
zk.Widget.$(jq(objCells).attr('id')).setValue(currVal);
zk.Widget.$(jq(objCells).attr('id')).fireOnChange();
} else { //otherwise we assume this is the last cell of the current tab
//So we get the current row, because we want to edit the cells in the same row in the next tabs
var currRow = jq(this).parents('tr').prevAll().length;
//finding the next cell, on the same row in the hidden tab and applying the same logic
objCellsHiddenTabs = jq(this).parents('.z-tabpanel').next().find('.z-row:eq(' + currRow + ')').find('.z-doublebox');
if (objCellsHiddenTabs.length) {
zk.Widget.$(jq(objCellsHiddenTabs).attr('id')).setValue(currVal);
zk.Widget.$(jq(objCellsHiddenTabs).attr('id')).fireOnChange();
}
}
The java code in the RowRenderer class looks something like this:
...
if (someBean != null) {
binder.bindBean("tBean", someBean);
Doublebox box = new Doublebox();
setDefaultStyle(box);
row.appendChild(box);
binder.addBinding(box, "value", "tBean.someSetter");
...
private void setDefaultStyle(Doublebox box) {
box.setFormat("#.00");
box.setConstraint("no negative,no empty");
box.setWidth("50px");
String customJS = ""; //the JS above
//this is used to visually see that you're editing multiple cells at once
String customJSNoFireOnChange = "jq(this).parents('td').nextAll().find('.z-doublebox').val(jq(this).val());";
box.setWidgetListener(Events.ON_CHANGING, customJSNoFireOnChange);
box.setWidgetListener(Events.ON_CHANGE, customJS);
}
What is interesting to notice is that ZK optimizes this fireOnChange Events and send only 1 ajax request to the server containing the updates to the necessary cells.

How to make Collapsible comment box like Stackoverflow

I am building a site and I have a list of status updates and I want to allow the users to write comments for each of of the items in the list
However I am trying to implement a UI similar to the way stack overflow works
specifically the collapsible comment form / list where a user clicks on add comment on the specific status update in the list, and below that item in the list the comment entry form shows up along with the specific comments already posted.
How do I accomplish this using Jquery?
Note: looking also for the markup example another words a working sample. Thanks
And yes if you could show Async postback that would be nice too

To load the content you can just hook up a click event to populate a div using the load method.
For example in the view you could have something like:-
<%= Html.ActionLink("Comments", "CommentList", "Questions", new { Id = this.ViewData.Model.Id }, new { id = "commentLink" })%>
<div id="commentContainer" style="display:none;">
Loading...
</div>
while the javascript to hook everything up would be:-
$(function() {
$("#commentLink").click(function() {
$("#commentContainer").toggle();
if ($("#commentContainer").is(":visible")) {
$("#commentContainer").load($(this).attr("href"));
} else {
$("#commentContainer").html("Loading..."); //Or just leave it as is...
}
return false; //Prevent default action
});
});

The quick approach (for just showing / hiding the comment area) would resemble something like this:
$(function(){
$('#id_of_element_to_use_for_click').click(function(){
$('#id_of_comment_area').slideToggle();
});
});
The jQuery site will provide you with doco on different approaches such as fades, slides or other combined animations.
Your "Comment Area" I've used in the example here would likely be a <div> tag that contains your existing comments, plus whatever textarea or text input box you wanted users to type their answers into.
Do you need to do an asynchronous postback?