I was wondering if anyone was aware of an example that shows multiple listeners to the YUI DDProxy, DD, or DDTarget onDragDrop event. Currently I have a hacked up example going. I'm using the http://developer.yahoo.com/yui/examples/datatable/dt_ddrows.html'>DataTable Reorder Rows example. I've modified it into several js classes. One object they override DDProxy for handles the onDragDrop event but it seems that if it's handled here then nothing else catches the event. Check the snip:
YAHOO.extend(YAHOO.example.DDRows, YAHOO.util.DDProxy, {
//snip
onDragDrop: function(e, id) {
if (id == "right-function-pane") {
alert("In the right drop place");
YAHOO.util.DragDropMgr.refreshCache();
}
}
In a class that does the creation of DDRows, I want to listen to the event here as well. Some actions are more appropriate in some places. I want to listen to the event in both places. Here's what I'm doing in class that builds the above:
onDropHandler: function(e, id) {
DragDropTable.myDataTable.deleteRow(YAHOO.util.DragDropMgr.dragCurrent.id);
},
rowInitializer: function() {
var i, id, myDDRow,
allRows = DragDropTable.myDataTable.getTbodyEl().rows;
for (i = 0; i < allRows.length; i++) {
id = allRows[i].id;
// Clean up any existing Drag instances
if (DragDropTable.myDTDrags[id]) {
DragDropTable.myDTDrags[id].unreg();
delete DragDropTable.myDTDrags[id];
}
// Create a Drag instance for each row
myDDRow = new YAHOO.example.DDRows(id);
myDDRow.srcData = DragDropTable.myDataTable.getRecord(id).getData();
myDDRow.onDragDrop = DragDropTable.onDropHandler;
DragDropTable.myDTDrags[id] = myDDRow;
}
}
It seems like if one is listening the other isn't working. I haven't found the syntax for allowing events to continue to bubble or to have multiple subscriptions to onDragDrop. Does anyone have the correct syntax?
Thanks
Josh Robinson
Related
Is there a way in Angular2 to have an event fired when my component becomes visible?
It is placed in a tabcontrol and I want to be notified when the user switches. I'd like my component to fire an event.
What I finally did (which is not very beautiful but works while I don't have a better way to do it...) is to use the ngAfterContentChecked() callback and handle the change myself.
#ViewChild('map') m;
private isVisible: boolean = false;
ngAfterContentChecked(): void
{
if (this.isVisible == false && this.m.nativeElement.offsetParent != null)
{
console.log('isVisible switched from false to true');
this.isVisible = true;
this.Refresh();
}
else if (this.isVisible == true && this.m.nativeElement.offsetParent == null)
{
console.log('isVisible switched from true to false');
this.isVisible = false;
}
}
There is no such event, but if you're using a tab control, the proper way to do this would be to create a tab change #Output for your tab control if it's custom, otherwise, most tab controls (like ng-bootstrap) have some tab change event as well.
If your component has to be aware of this, you can use this tab change event to detect which tab is visible, and if you know which tab is visible, you also know if your component is visible or not. So you can do something like this:
onTabChange(event) {
this.currentTab = /** Get current tab */;
}
And then you can send it to your component itself if you have an input:
#Input() activated: boolean = false;
And then you can apply it with:
<my-component [activated]="currentTab == 'tabWithComponent'"></my-component>
Now you can listen to OnChanges to see if the model value activated changed to true.
You can also refactor this to use a service with an Observable like this:
#Injectable()
export class TabService {
observable: Observable<any>;
observer;
constructor() {
this.observable = Observable.create(function(observer) {
this.observer = observer;
});
}
}
When a component wishes to listen to these changes, it can subscribe to tabService.observable. When your tab changes, you can push new items to it with tabService.observer.next().
You can use the ngAfterViewInit() callback
https://angular.io/docs/ts/latest/guide/lifecycle-hooks.html
Update
The new Intersection Observer API can be used for that
https://developer.mozilla.org/en-US/docs/Web/API/Intersection_Observer_API
See also https://stackoverflow.com/a/44670818/217408
For those watching at home, you can now use ngAfterContentInit() for this, at least on Ionic anyway.
https://angular.io/guide/lifecycle-hooks
Best way to work around this limitation of Angular is to use a shared service that provides a Subject your component can subscribe to. That way new values could be pushed onto the Observable and the components which subscribe get the newest data and can act accordingly.
Fyi: The difference between a normal Observable and a Subject is that a Subject is multicast whereas an Observable could only be subscribed to by one Subscriber.
As a small example I show you a possible implementation of a shared-service and following the subscription inside the component that needs this new data.
Shared-service:
// ...
private actualNumberSubject = new Subject<number>()
public actualNumber$ = this.actualNumberSubject.asObservable()
/**
* #info CONSTRUCTOR
*/
constructor() {}
/**
* #info Set actual number
*/
setActualNumber(number: number) {
this.actualNumberSubject.next(internalNumber)
}
// ...
Push new value onto the subject from anywhere where shared.service is imported:
// ...
this.sharedService.setActualNumber(1)
Subscribe to sharedService.actualNumber$ in component to process/display that new data:
// ...
this.sharedService.actualNumber$.subscribe(number => {
console.log(number)
// e.g. load data freshly, etc.
})
// ...
I have the same purpose and cannot get a satisfy approach to it. The first answer will call so many times.
There is a compromised way I used, of course, not elegant either.
In parent component, I set a method:
parentClick() {
setTimeout(() => {
// TO-DO
This.commonService.childMethod();
}, time);
}
Maybe the method not accurate in time, but in some way, you reach the destiny.
Collaboration Mode:
What is the best way to propagate changes from Client #1's canvas to client #2's canvas? Here's how I capture and send events to Socket.io.
$scope.canvas.on('object:modified',function(e) {
Socket.whiteboardMessage({
eventId:'object:modified',
event:e.target.toJSON()
});
});
On the receiver side, this code works splendidly for adding new objects to the screen, but I could not find documentation on how to select and update an existing object in the canvas.
fabric.util.enlivenObjects([e.event], function(objects) {
objects.forEach(function(o) {
$scope.canvas.add(o);
});
});
I did see that Objects have individual setters and one bulk setter, but I could not figure out how to select an existing object based on the event data.
Ideally, the flow would be:
Receive event with targeted object data.
Select the existing object in the canvas.
Perform bulk update.
Refresh canvas.
Hopefully someone with Fabric.JS experience can help me figure this out. Thanks!
UPDATED ANSWER - Thanks AJM!
AJM was correct in suggesting a unique ID for every newly created element. I was also able to create a new ID for all newly created drawing paths as well. Here's how it worked:
var t = new fabric.IText('Edit me...', {
left: $scope.width/2-100,
top: $scope.height/2-50
});
t.set('id',randomHash());
$scope.canvas.add(t);
I also captured newly created paths and added an id:
$scope.canvas.on('path:created',function(e) {
if (e.target.id === undefined) {
e.target.set('id',randomHash());
}
});
However, I encountered an issue where my ID was visible in console log, but it was not present after executing object.toJSON(). This is because Fabric has its own serialization method which trims down the data to a standardized list of properties. To include additional properties, I had to serialize the data for transport like so:
$scope.canvas.on('object:modified',function(e) {
Socket.whiteboardMessage({
object:e.target.toJSON(['id']) // includes "id" in output.
})
});
Now each object has a unique ID with which to perform updates. On the receiver's side of my code, I added AJM's object-lookup function. I placed this code in the "startup" section of my application so it would only run once (after Fabric.js is loaded, of course!)
fabric.Canvas.prototype.getObjectById = function (id) {
var objs = this.getObjects();
for (var i = 0, len = objs.length; i < len; i++) {
if (objs[i].id == id) {
return objs[i];
}
}
return 0;
};
Now, whenever a new socket.io message is received with whiteboard data, I am able to find it in the canvas via this line:
var obj = $scope.canvas.getObjectById(e.object.id);
Inserting and removing are easy, but for updating, this final piece of code did the trick:
obj.set(e.object); // Updates properties
$scope.canvas.renderAll(); // Redraws canvas
$scope.canvas.calcOffset(); // Updates offsets
All of this required me to handle the following events. Paths are treated as objects once they're created.
$scope.canvas.on('object:added',function(e) { });
$scope.canvas.on('object:modified',function(e) { });
$scope.canvas.on('object:moving',function(e) { });
$scope.canvas.on('object:removed',function(e) { });
$scope.canvas.on('path:created',function(e) { });
I did something similar involving a single shared canvas between multiple users and ran into this exact issue.
To solve this problem, I added unique IDs (using a javascript UUID generator) to each object added to the canvas (in my case, there could be many users working on a canvas at a time, thus I needed to avoid collisions; in your case, something simpler could work).
Fabric objects' set method will let you add an arbitrary property, like an id: o.set('id', yourid). Before you add() a new Fabric object to your canvas (and send that across the wire), tack on an ID property. Now, you'll have a unique key by which you can pick out individual objects.
From there, you'd need a method to retrieve an object by ID. Here's what I used:
fabric.Canvas.prototype.getObjectById = function (id) {
var objs = this.getObjects();
for (var i = 0, len = objs.length; i < len; i++) {
if (objs[i].id == id) {
return objs[i];
}
}
return null;
};
When you receive data from your socket, grab that object from the canvas by ID and mutate it using the appropriate set methods or copying properties wholesale (or, if getObjectById returns null, create it).
I have a mobile app that receives a push notification, when it does, I know there is a row that that needs to be updated. I have tried two methods for retrieving just that one:
var row = data_source.get(<id>);
row.dirty = true;
data_source.sync();
This tries to fire an UPDATE, which I could shoe-horn into doing what I want, but it's conceptually wrong.
The other option that I have tried:
data_source.read( { id : <id> } );
Which fires off a READ request, with the ID in options.data. When I try to hook this up, kendo complains about not getting an array back, and when I make the response into an array, it doesn't seem to work either.
How am I supposed to do this? GET it outside the context of the DataSource, and set the relevant parts, and then set the dirty bit to false?
Kendo doesn't do single row read out of the box. If its not feasible to do full read(), you have to do what you proposed. Try following :
1) make your server side read method to accept requests with or without id, without to read all items, with to read your one row.
2) use parameter map together with isPushNotificaton flag to control the read request params
parameterMap: function(data, type) {
if (type == "read") {
if (isPushNotificaton)
return { id : yourId };
else
return { id : 0}; // get all
}
}
3) use requestEnd to decide how to deal with read result
requestEnd: function(e) {
var type = e.type;
if (e.type == 'read') {
// examine the response(by count/add additional flags into response object)
var isFullReadResponse = ...;
if (!isFullReadResponse) {
// DIY
e.preventDefault();
UpdateSingleRow(response, datasource.data());
}
}
}
4) Implement UpdateSingleRow method as you proposed - .."and set the relevant parts, and then set the dirty bit to false", (Refresh a single Kendo grid row)
I'm working on a WPF application that monitors numerous folders in an Outlook Shared Mailbox. I have wired up ItemAdd and ItemRemove event handlers to a Folder.Items object.
Everything works great for a few minutes. But as time goes on, the event handling seems to go "poof". Some folders will still recognize add and remove, others will only see removes, while others are blind to any activity. To me it seems like the event handlers are being garbage collected, but my Items object IS declared as a global variable in the class it sits in, so I don't see how they could be GC'd out.
Are there any pitfalls I should be aware of with Outlook Folder.Items events? I have a previous, simpler application that works by similar processes that works fine for extended periods of time. There is no intrinsic difference, as far as Item event handling goes, between my old app and this new one. I'm really at a loss as to what's causing this.
Below is the relevant code. To bring some context to this, what I'm doing is, for each Folder in the Outlook Shared Mailbox a "TicketView" UserControl is created which represents the contents (MailItems) of that folder. This TicketView is a simple ListBox that may contain between 0 to a couple dozen MailItems -- nothing excessive.
public partial class TicketView : UserControl
{
private Folder _thisFolder = null;
private TicketCollection _thisTicketColl = null;
private Items _thisItems = null;
public TicketView(Folder folder)
{
InitializeComponent();
_thisTicketColl = this.FindResource("TicketCollection") as TicketCollection;
_thisFolder = folder;
_thisItems = folder.Items;
SetFolderEvents();
Refresh();
}
private void SetFolderEvents()
{
_thisItems.ItemAdd += new ItemsEvents_ItemAddEventHandler(delegate
{
Refresh();
});
_thisItems.ItemRemove += new ItemsEvents_ItemRemoveEventHandler(delegate
{
Refresh();
});
}
public void Refresh()
{
BackgroundWorker worker = new BackgroundWorker();
worker.DoWork += new DoWorkEventHandler(delegate(object sender, DoWorkEventArgs e)
{
string[] fields = new string[] { "Subject", "SenderName", "SentOn", "EntryID" };
var olTable = TicketMonitorStatics.GetOutlookTable(_thisFolder, fields, filter);
olTable.Sort("SentOn", true);
var refreshedList = new List<Ticket>();
while (!olTable.EndOfTable)
{
var olRow = olTable.GetNextRow();
refreshedList.Add(new Ticket
{
Subject = olRow["Subject"],
Sender = olRow["SenderName"],
SentOn = olRow["SentOn"],
EntryID = olRow["EntryID"]
});
};
e.Result = refreshedList;
});
worker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(delegate(object sender, RunWorkerCompletedEventArgs e)
{
var refreshedList = e.Result as List<Ticket>;
UpdateTicketList(refreshedList);
worker.Dispose();
});
worker.RunWorkerAsync();
}
private void UpdateTicketList(List<Ticket> newList)
{
_thisTicketColl.Clear();
foreach (Ticket t in newList)
{
_thisTicketColl.Add(t);
}
}
}
}
Outlook events should not be used for any kind of synchronization. They are designed to be used for the UI purposes only and can be dropped under heavy loads or if a network error occurs (if you are using an online store).
You can use events only as a hint that your code needs to run sooner rather than later.
You can use the IExchangeExportChanges MAPI interface (C++ or Delphi only) to perform synchronization; this is the same API used by Outlook to synchronize its cached folders. If you are not using C++ or Delphi, you can use Redemption (I am its author) and its RDOFolderSynchronizer object.
So, I took some code from this Microsoft provided Example which allows me to use the jquery validate unobtrusive library to parse validation error message returned from my server and display them in the UI. They have a video demonstrating this. So, here is the piece of Javascript code I'm using:
$.validator.addMethod("failure", function () { return false; });
$.validator.unobtrusive.adapters.addBool("failure");
$.validator.unobtrusive.revalidate = function (form, validationResult) {
$.removeData(form[0], 'validator');
var serverValidationErrors = [];
for (var property in validationResult) {
//var elementId = property.toLowerCase();
var item = form.find('#' + property);
if (item.length < 1) { item = form.find('#' + property.replace('.', '_')); }
serverValidationErrors.push(item);
item.attr('data-val-failure', validationResult[property].join(', '));
jQuery.validator.unobtrusive.parseElement(item[0]);
}
form.valid();
$.removeData(form[0], 'validator');
$.each(serverValidationErrors, function () {
this.removeAttr('data-val-failure');
jQuery.validator.unobtrusive.parseElement(this[0]);
});
};
So then after a AJAX form post in the handle error function I would do something like this:
$.validator.unobtrusive.revalidate(form, { 'PhysicalAddress.CityName': ['You must select a valid city'] });
Where PhysicalAddress.CityName is the name of my viewmodel property and html input field. So, it knows to put the validation message next to the correct html element.
This works 1 time. Then when they hit submit again and my code calls the unobtrusive.revalidate method again.. it doesnt work. It only shows the validation message one time then after that the validation message disappears for good.
Does anyone have any idea as to why this might be happening?.. I stepped through the revalidate method and no errors were thrown and everything seems like it should work.. but the unobtrusive library for some reason is not re-binding the validation error message.
Thanks
Probably this behavior depends on a known problem of the jQuery validation plugin: dynamically adding new validation rules for elements works just once! Further attempts are rejected because the plugin think they are a duplicated attempt to define the already defined rules.
This is the reason why the $.validator.unobtrusive.parse doesn't work when you add newly created content (when for instance you add a new row to a collection of items). There is a patch for the $.validator.unobtrusive.parse that you might try to apply also to the revalidate function....but it is better to rewrite it from scratch in a different way. The revalidate function usse the validation plugin just to place at the right place all validation errors, then it tries to reset the state of the validation plugin. However, deleting the validator object from the form is not enough to cancel all job done since there is another object contained in the form.data('unobtrusiveValidation'), where form is a variable containing the form being validated...This data are not reset by the revalidate function...and CANNOT be reset since resetting them would cause the cancellation of ALL client side validation rules.
Maybe this problem has been solved in the last version of the validation plugin, so try to update to the last version with nuget.
If this doesn't solve your issue I can pass you an analogous function implemented in a completely different way(it mimics what the server does on the server side to show server side errors). It will be contained in the upcoming version of the Mvc Controls toolkit. However, if you give me a couple of days (I will be very busy for 2 days) I can extract it from there with its dependencies so you can use it. Let me know if you are interested.
Below the code I promised. It expects an array whose elements are:
{
id:id of the element in error
errors:array of strings errors associated to the element
}
It accepts several errors for each element but just display di first one for each element
id is different from the name because . [ ] an other special char are replaced by _
You can transform name into id on the sever with
htmlName.Replace('$', '_').Replace('.', '_').Replace('[', '_').Replace(']', '_');
or on the client in javascript with:
name.replace(/[\$\[\]\.]/g, '_');
function remoteErrors(jForm, errors) {
//////////
function inner_ServerErrors(elements) {
var ToApply = function () {
for (var i = 0; i < elements.length; i++) {
var currElement = elements[i];
var currDom = $('#' + currElement.id);
if (currDom.length == 0) continue;
var currForm = currDom.parents('form').first();
if (currForm.length == 0) continue;
if (!currDom.hasClass('input-validation-error'))
currDom.addClass('input-validation-error');
var currDisplay = $(currForm).find("[data-valmsg-for='" + currElement.name + "']");
if (currDisplay.length > 0) {
currDisplay.removeClass("field-validation-valid").addClass("field-validation-error");
replace = $.parseJSON(currDisplay.attr("data-valmsg-replace")) !== false;
if (replace) {
currDisplay.empty();
$(currElement.errors[0]).appendTo(currDisplay);
}
}
}
};
setTimeout(ToApply, 0);
}
/////////
jForm.find('.input-validation-error').removeClass('input-validation-error');
jForm.find('.field-validation-error').removeClass('field-validation-error').addClass('field-validation-valid');
var container = jForm.find("[data-valmsg-summary=true]");
list = container.find("ul");
list.empty();
if (errors.length > 0) {
$.each(errors, function (i, ival) {
$.each(ival.errors, function (j, jval) {
$("<li />").html(jval).appendTo(list);
});
});
container.addClass("validation-summary-errors").removeClass("validation-summary-valid");
inner_ServerErrors(errors);
setTimeout(function () { jForm.find('span.input-validation-error[data-element-type]').removeClass('input-validation-error') }, 0);
}
else {
container.addClass("validation-summary-valid").removeClass("validation-summary-errors");
}
}
function clearErrors(jForm) {
remoteErrors(jForm, []);
}