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C# variable value only update once when called in Javascript

I've look an found only a similar post and didn't really answer my question or maybe they did but I didn't understand. The post I read was this one: Why does this javascript variable I'm creating via C# only get updated once?
I'm using a paged gridview and every time it's object data source runs the SelectCountMethod, I use the returning value on javascript. But, I've noticed that even thought that same returned value changes, on the server side. On javascript this value doesn't update.
My program is quite long but I'll use a basic example and hopefully some of you will understand it.
Client side:
function SomeFuntion()
{
alert("<%=num%>");
}
Server side:
//Global variable
Public Static int num = 0;
Public int SelectCountMethod()
{
var num = SomeMethod(); //Returns int
return num;
}
For example, on the server side num returns 60 and then this value updates to 7. On the server side num equals 7 but on the client side it's still 60. Is there a way to update the client sides value?
I apologies for my poor typing skills, English is not my native language.
Some examples might be helpful and thanks in advance.
I noticed that it doesn't mater where I update this variable(on selectCount method or any other method), on the client side doesn't update.

Taking a look at your client-side code, the "<%=num%>" is actually run on the server. If you examined the source in your browser, what you'll see is:
function SomeFuntion()
{
alert("60");
}
As you can see--there is no variable to update. In order to see that "60" change to "7", you'd have to refresh the client to pick up the new value that the server has for "num".

You could modify your JS method like this
var myMsg = <%=num%>;
function SomeFuntion()
{
alert(myMsg);
}
and in the codebehind
public int num = 60;
public int SelectCountMethod()
{
num = SomeMethod(); //Returns int
ScriptManager.RegisterStartupScript(this,
this.GetType(),
"Funct",
"myMsg = " + num + ";",
true);
return num;
}
So every time your method SelectCountMethod() is called, your JS variable myMsg get a new value because of the line ScriptManager.RegisterStartupScript

Without your server side code, we won't be able to find the ideal solution. However, you could potentially do the following:
Use a Hidden Field to store the value.
Use a global variable for the page, to pass the value to global variable in your JavaScript.
The easiest would be the Hidden Field, the reason is you can easily modify the data on both Client and Server without any real issues. You'll want to ensure that you do not modify the state to often.
<input type="hidden" id="hdTimer" runat="server" />
Then you can do your JavaScript, such as:
$('#Example').on('change', function () {
$('#hdTimer').val('60');
});
Now throughout the Client code you'll be able to modify the field with no issues, but when you need to submit a form, for a PostBack. You can use the field server side:
var content = hdTimer.value;
As I noted though, excessive cross manipulation may cause an issue at some point. Depending on the complexity. Your other approach would be the Global.
// Server Side
var example = 60;
protected void Page_Load(object sender, EventArgs e)
{
}
So this Global will hold the value, but when you reinitialize the value at Page Load it will hold be able to push an updated value to your JavaScript:
//Client Side:
var example = '<%= example %>';
The key though, will be to ensure you properly reinitialize the value.
When you do a PostBack your page is reinitialized, which can modify values on you if you aren't aware. This is incredibly important.

Use an HttpHandler and jQuery. Google is your friend, there are several examples on SO as well.

I found a possible solution, inefficient, but it will have to do. I have a search textbox that every time the search button is clicked, updates the grid view with the retrieved data from a data base. When the Onclick is called it binds the data source with the gridView. What I did was call the SelectCountMethod again right below the binding and used the same parameters I had stored on the Object data source as paramaters for the selectCountMethod. Then the amount returned by the selectCount I stored it on a hiddenField and that's it.
//Global variables
string _param1 = string.Empty,
_param2 = string.Empty;
//On click method for search btn
protected void OnSearch(object sender, EventArgs e)
{
gv.DataBind();
someHiddenField = SelectCountMethod(param1, param2);
}
protected void OnSelecting(object sender, ObjectDataSourceSelectingEventArgs e)
{
try
{
e.InputParameters["Param1"] = param1;
_param1 = param1
e.InputParameters["Param2"] = param2;
_param2 = param2;
}
catch (Exception ex)
{
cvServerError.IsValid = false;
cvServerError.ErrorMessage = ex.Message;
}
}

Invoking a JavaScript function from oncomplete handler of p:remoteCommand - simulating the same using some JavaScript code

Caution : Although this question covers long textual information with a mess of Java code snippets, it is merely targeted to JavaScript/jQuery and a bit of PrimeFaces stuff (just <p:remoteCommand>) as mentioned in the introductory part in the beginning.
I am receiving a JSON message from WebSockets (Java EE 7 / JSR 356 WebSocket API) as follows.
if (window.WebSocket) {
var ws = new WebSocket("wss://localhost:8181/ContextPath/AdminPush");
ws.onmessage = function (event) {
jsonMsg=event.data;
var json = JSON.parse(jsonMsg);
var msg=json["jsonMessage"];
if (window[msg]) {
window[msg](); //It is literally interpreted as a function - updateModel();
}
};
}
In the above code, event.data contains a JSON string {"jsonMessage":"updateModel"}. Thus, msg will contain a string value which is updateModel.
In the following segment of code,
if (window[msg]) {
window[msg](); //It is literally interpreted as a JavaScript function - updateModel();
}
window[msg](); causes a JavaScript function associated with a <p:remoteCommand> to be invoked (which in turn invokes an actionListener="#{bean.remoteAction}" associated with the <p:remoteCommand>).
<p:remoteCommand name="updateModel"
actionListener="#{bean.remoteAction}"
oncomplete="notifyAll()"
process="#this"
update="#none"/>
update="#none" is not necessarily needed.
After receiving this message, I need to notify all the associated clients about this update. I use the following JavaScript function to do so which is associated with the oncomplete handler of the above <p:remoteCommand>.
var jsonMsg;
function notifyAll() {
if(jsonMsg) {
sendMessage(jsonMsg);
}
}
Notice that the variable jsonMsg is already assigned a value in the first snippet - it is a global variable. sendMessage() is another JavaScript function that actually sends a notification about this update to all the associated clients through WebSockets which is not needed in this question.
This works well but is there a way to do some magic in the following condition
if (window[msg]) {
window[msg]();
//Do something to call notifyAll() on oncomplete of remote command.
}
so that the notifyAll() function can be invoked through some JavaScript code directly (which is currently attached to oncomplete of <p:remoteCommand> and the expected JavaScript code (or even something else) should simulate this oncomplete) basically eliminating the need to depend upon a global JavaScript variable (jsonMSg)?
Edit : The problem I am trying to solve (it may be considered to be additional information).
When an admin for example, makes some changes (by means of DML operations) to a JPA entity named Category, entity listeners are triggered which in turn causes a CDI event to be raised as follows.
#ApplicationScoped
public class CategoryListener {
#PostPersist
#PostUpdate
#PostRemove
public void onChange(Category category) throws NamingException {
BeanManager beanManager = (BeanManager) InitialContext.doLookup("java:comp/BeanManager");
beanManager.fireEvent(new CategoryChangeEvent(category));
}
}
Needless to say that the entity Category is designated with the annotation #EntityListeners(CategoryListener.class).
Just one side note (completely off topic) : Getting an instance of BeanManager through a JNDI look-up as done in the preceding code snippet is temporary. The GlassFish Server 4.1 having the Weld version 2.2.2 final fails to inject the CDI event javax.enterprise.event.Event<T> which is supposed to be injected as follows.
#Inject
private Event<CategoryChangeEvent> event;
And then, the event can be fired as follows with reference to the relevant code snippet above.
event.fire(new CategoryChangeEvent(category));
This event is observed in the web project as follows.
#ApplicationScoped
public class RealTimeUpdate {
public void onCategoryChange(#Observes CategoryChangeEvent event) {
AdminPush.sendAll("updateModel");
}
}
Where an admin uses his own end-point as follows (AdminPush.sendAll("updateModel"); is invoked manually therein).
#ServerEndpoint(value = "/AdminPush", configurator = ServletAwareConfig.class)
public final class AdminPush {
private static final Set<Session> sessions = new LinkedHashSet<Session>();
#OnOpen
public void onOpen(Session session, EndpointConfig config) {
if (Boolean.valueOf((String) config.getUserProperties().get("isAdmin"))) {
sessions.add(session);
}
}
#OnClose
public void onClose(Session session) {
sessions.remove(session);
}
private static JsonObject createJsonMessage(String message) {
return JsonProvider.provider().createObjectBuilder().add("jsonMessage", message).build();
}
public static void sendAll(String text) {
synchronized (sessions) {
String message = createJsonMessage(text).toString();
for (Session session : sessions) {
if (session.isOpen()) {
session.getAsyncRemote().sendText(message);
}
}
}
}
}
Here only an admin is allowed to use this end-point. All other users are prevented from creating a WebSocket session using a conditional check in the onOpen() method.
session.getAsyncRemote().sendText(message); inside the foreach loop sends a notification (in the form of a JSON message) to the admin about these changes made in the entity Category.
As shown in the first code snippet, window[msg](); invokes an action method (through a <p:remoteCommand> as shown earlier) associated with an application scoped bean - actionListener="#{realTimeMenuManagedBean.remoteAction}".
#Named
#ApplicationScoped
public class RealTimeMenuManagedBean {
#Inject
private ParentMenuBeanLocal service;
private List<Category> category;
private final Map<Long, List<SubCategory>> categoryMap = new LinkedHashMap<Long, List<SubCategory>>();
// Other lists and maps as and when required for a dynamic CSS menu.
public RealTimeMenuManagedBean() {}
#PostConstruct
private void init() {
populate();
}
private void populate() {
categoryMap.clear();
category = service.getCategoryList();
for (Category c : category) {
Long catId = c.getCatId();
categoryMap.put(catId, service.getSubCategoryList(catId));
}
}
// This method is invoked through the above-mentioned <p:remoteCommand>.
public void remoteAction() {
populate();
}
// Necessary accessor methods only.
}
All other users/clients (who are on a different panel - other than the admin panel) should only be notified when actionListener="#{realTimeMenuManagedBean.remoteAction}" finishes in its entirely - must not happen before the action method finishes - should be notified through the oncomplate event handler of <p:remoteCommand>. This is the reason why two different end-points have been taken.
Those other users use their own end-point:
#ServerEndpoint("/Push")
public final class Push {
private static final Set<Session> sessions = new LinkedHashSet<Session>();
#OnOpen
public void onOpen(Session session) {
sessions.add(session);
}
#OnClose
public void onClose(Session session) {
sessions.remove(session);
}
#OnMessage
public void onMessage(String text) {
synchronized (sessions) {
for (Session session : sessions) {
if (session.isOpen()) {
session.getAsyncRemote().sendText(text);
}
}
}
}
}
The method annotated with #OnMessage comes to play, when a message is sent through oncomplete of <p:remoteCommand> as shown above.
Those clients use the following JavaScript code to just fetch the new values from the above-mentioned application scoped bean (the bean was already queried adequately by the admin from the database. Thus, there is no need to ridiculously query it again by each and every individual client separately (other than the admin). Hence, it is an application scoped bean).
if (window.WebSocket) {
var ws = new WebSocket("wss://localhost:8181/ContextPath/Push");
ws.onmessage = function (event) {
var json = JSON.parse(event.data);
var msg = json["jsonMessage"];
if (window[msg]) {
window[msg]();
}
};
$(window).on('beforeunload', function () {
ws.close();
});
}
In conjunction with the following <p:remoteCommand>.
<p:remoteCommand name="updateModel"
process="#this"
update="parentMenu"/>
Where parentMenu - the component to be updated by this <p:remoteCommand> is an id of a container JSF component <h:panelGroup> which contains a plain CSS menu with a bunch of <ui:repeat>s.
Hope this makes the scenario clearer.
Update :
This question has been answered precisely here based on <p:remoteCommand> (As to the concrete question, the sole question was to remove a dependency upon a global JavaScript variable as stated in the introductory part of this question).

I don't think I understood every aspect of your problem, but anyway I try to help a bit. Note that I do not know PrimeFaces, so all I did was reading the docs.
What I understand is, that you try to get rid of the global variable. But I am afraid, I do not think this is possible.
The problem here is, that PrimeFaces does not allow you to pass something transparently from your invocation of the remote call further to the oncomplete call (except you pass it to a Java code of the Bean and then back to the UI, and this usually is not what you want).
However, I hope, you can come very close to it.
Part 1, JS returns early
Please also note that there probably is some misconception about Java and JavaScript.
Java is multithreaded and runs several commands in parallel, while JavaScript is singlethreaded and usually never waits for something to complete. Doing things asychronously is mandatory to get a responsive Web-UI.
Hence your remoteCommand invocation (seen from the JS side) will (usually, async case) return long before the oncomplete handler will be invoked. That means, if window[msg]() returns, you are not finished with the remoteCommand yet.
So what you want to manage with following code
if (window[msg]) {
window[msg]();
//Do something to call notifyAll() on oncomplete of remote command.
dosomethinghere();
}
will fail. dosomethinghere() will not be invoked when the remoteCommand returned (as JS does not want to wait for some event, which might never happen). This means, dosomethinghere() will be invoked when the Ajax-request was just opened to the remote (to the Java application).
To run something after the Ajax call finished, this must be done in the oncomplete routine (or onsuccess). This is why it's there.
Part 2, validate msg
Please note something different about window[msg](). This can be considered a bit dangerous if you cannot trust the pushed message completely. window[msg]() essentially runs any function named with the contents of the variable msg. For example if msg happen to be close then window.close() will be run, which probably is not what you want.
You should make sure, msg is one expected word, and decline all other words. Example code for this:
var validmsg = { updateModel:1, rc:1 }
[..]
if (validmsg[msg] && window[msg])
window[msg]();
Part 3: How to handle multiple JSON messages in parallel
The global variable has some drawback. There is only one. If you happen to receive another JSON message on the WebSocket while the previous message still is processing in the remoteCommand, this will overwrite the previous message. So the notifyAll() will see the newer message twice, the old one is lost.
A classical race condition. What you must do is, to create something like a registry to register all the messages, and then pass some value to notifyAll() to tell, which of the registered messages shall be processed.
With only a little change, you can either parallely (here) or serially (Part 4) process the messages.
First, create a counter to be able to distinguish the messages. Also an object to store all the messages. And we declare all valid messages we expect (see Part 2):
var jsonMsgNr = 0;
var jsonMessages = {};
var validmsg = { updateModel:1 }
Now add a message each time we receive one:
if (window.WebSocket) {
var ws = new WebSocket("wss://localhost:8181/ContextPath/AdminPush");
ws.onmessage = function (event) {
var jsonMsg = event.data;
var json = JSON.parse(jsonMsg);
var msg=json["jsonMessage"];
if (validmsg[msg] && window[msg]) {
var nr = ++jsonMsgNr;
jsonMessages[nr] = { jsonMsg:jsonMsg, json:json };
To be able to pass the nr to NotifyAll() an additional parameter needs to be passed to the Bean. Let's call it msgNr:
// Following might look a bit different on older PrimeFaces
window[msg]([{name:'msgNr', value:nr}]);
}
}
}
Perhaps have a look into https://stackoverflow.com/a/7221579/490291 for more on passing values this way.
The remoteAction bean now gets an additional parameter msgNr passed, which must be passed back via Ajax.
Unfortunately I have no idea (sorry) how this looks in Java. So make sure, your answer to the AjaxCall copies the msgNr out again.
Also, as the documentation is quiet about this subject, I am not sure how the parameters are passed back to the oncomplete handler. According to the JavaScript debugger, notifyAll() gets 3 parameters: xhdr, payload, and pfArgs. Unfortunately I was not able to setup a test case to find out how things look like.
Hence the function looks a bit like (bear with me, please):
function notifyAll(x, data, pfArgs) {
var nr = ???; // find out how to extract msgNr from data
var jsonMsg = jsonMessages[nr].jsonMsg;
var json = jsonMessages[nr].json;
jsonMessages[nr] = null; // free memory
sendMessage(jsonMsg);
dosomething(json);
}
If you split this into two functions, then you can invoke the notifyAll() from other parts in your application:
function notifyAll(x, data, unk) {
var nr = ???; // find out how to extract msgNr from data
realNotifyAll(nr);
}
function realNotifyAll(nr) {
if (!(nr in jsonMessages)) return;
var jsonMsg = jsonMessages[nr].jsonMsg;
var json = jsonMessages[nr].json;
delete jsonMessages[nr]; // free memory
sendMessage(jsonMsg);
dosomething(json);
}
Some things here are a bit redundant. For example you perhaps do not need the json element in jsonMessages or want to parse the json again to spare some memory in case the json is very big. However the code is meant not to be optimal but to be easy to adjust to your needs.
Part 4: serialize requests
Now to the changes to serialize things. That's quite easy by adding some semaphore. Semaphores in JavaScript are just variables. This is because there is only one global thread.
var jsonMsgNr = 0;
var jsonMessages = {};
var validmsg = { updateModel:1 }
var jsonMsgNrLast = 0; // ADDED
if (window.WebSocket) {
var ws = new WebSocket("wss://localhost:8181/ContextPath/AdminPush");
ws.onmessage = function (event) {
var jsonMsg = event.data;
var json = JSON.parse(jsonMsg);
var msg=json["jsonMessage"];
if (validmsg[msg] && window[msg]) {
var nr = ++jsonMsgNr;
jsonMessages[nr] = { jsonMsg:jsonMsg, json:json };
if (!jsonMsgNrLast) { // ADDED
jsonMsgNrLast = nr; // ADDED
window[msg]([{name:'msgNr', value:nr}]);
}
}
}
}
function realNotifyAll(nr) {
if (!(nr in jsonMessages)) return;
var jsonMsg = jsonMessages[nr].jsonMsg;
var json = jsonMessages[nr].json;
delete jsonMessages[nr]; // free memory
sendMessage(jsonMsg);
dosomething(json);
// Following ADDED
nr++;
jsonMsgNrLast = 0;
if (nr in jsonMessages)
{
jsonMsgNrLast = nr;
window[jsonMessages[nr].json.msg]([{name:'msgNr', value:nr}]);
}
}
Note: jsonMsgNrLast could be just a flag (true/false). However having the current processed number in a variable perhaps can help somewhere else.
Having said that, there is a starvation problem in case something fails in sendMessage or dosomething. So perhaps you can interleave it a bit:
function realNotifyAll(nr) {
if (!(nr in jsonMessages)) return;
var jsonMsg = jsonMessages[nr].jsonMsg;
var json = jsonMessages[nr].json;
delete jsonMessages[nr]; // free memory
nr++;
jsonMsgNrLast = 0;
if (nr in jsonMessages)
{
jsonMsgNrLast = nr;
// Be sure you are async here!
window[jsonMessages[nr].json.msg]([{name:'msgNr', value:nr}]);
}
// Moved, but now must not rely on jsonMsgNrLast:
sendMessage(jsonMsg);
dosomething(json);
}
This way the AJAX request is already send out while sendMessage is running. If now dosomething has a JavaScript error or similar, the messages are still processed correctly.
Please note: All this was typed in without any tests. There might be syntax errors or worse. Sorry, I tried my best. If you find a bug, edit is your friend.
Part 5: Direct Invocation from JS
Now, with all this in place and a serialized Run, you can always invoke the previous notifyAll() using realNotifyAll(jsonMsgNrLast). Or you can display the jsonMessages in a list and choose any arbitrary number.
By skipping the call to window[jsonMessages[nr].json.msg]([{name:'msgNr', value:nr}]); (and above window[msg]([{name:'msgNr', value:nr}]);) you also can halt the Bean processing and run it on-demand using the usual JQuery callbacks. For this create a function and change the code a bit again:
var jsonMsgNr = 0;
var jsonMessages = {};
var validmsg = { updateModel:1 }
var jsonMsgNrLast = 0;
var autoRun = true; // ADDED, set false control through GUI
if (window.WebSocket) {
var ws = new WebSocket("wss://localhost:8181/ContextPath/AdminPush");
ws.onmessage = function (event) {
var jsonMsg = event.data;
var json = JSON.parse(jsonMsg);
if (validmsg[msg] && window[msg]) {
var nr = ++jsonMsgNr;
jsonMessages[nr] = { jsonMsg:jsonMsg, json:json };
updateGuiPushList(nr, 1);
if (autoRun && !jsonMsgNrLast) {
runRemote(nr);
}
}
}
}
function realNotifyAll(nr) {
if (!(nr in jsonMessages)) return;
var jsonMsg = jsonMessages[nr].jsonMsg;
var json = jsonMessages[nr].json;
delete jsonMessages[nr]; // free memory
updateGuiPushList(nr, 0);
jsonMsgNrLast = 0;
if (autoRun)
runRemote(nr+1);
// Moved, but now must not rely on jsonMsgNrLast:
sendMessage(jsonMsg);
dosomething(json);
}
function runRemote(nr) {
if (nr==jsonMsgNrLast) return;
if (nr in jsonMessages)
{
if (jsonMsgNrLast) { alert("Whoopsie! Please wait until processing finished"); return; }
jsonMsgNrLast = nr;
updateGuiPushList(nr, 2);
// Be sure you are async here!
window[jsonMessages[nr].json.msg]([{name:'msgNr', value:nr}]);
}
}
Now you can start the processing with runRemote(nr) and invoke the completion function with realNotifyAll(nr).
The function updateGuiPushList(nr, state) with state=0:finished 1=added 2=running is the callback to your GUI code which updates the on-screen list of waiting pushes to process. Set autoRun=false to stop automatic processing and autoRun=true for automatic processing.
Note: After setting autoRun from false to true you need to trigger runRemote once with the lowest nr, of course.

Auto update timeAgo value from submitted date

EDIT: I think I should make things more obvious.
What I am trying to do is to make the function that displays the "time ago" from the submitted date of the post auto refresh every minute so that it stays relatively accurate even if the template is not re rendered.
I'd like to auto update my timeago value in my template but it is not working.
I've tried to set up my code with a reactive function, based on the answer to a similar question (https://stackoverflow.com/a/17933506)
Here's my code:
var timeAgoDep = new Deps.Dependency(); // !!!
var timeAgo;
var timeAgoInterval;
Template.postItem.created = function() {
function getTimeago() {
//var now = new Date();
timeAgo = moment(this.submitted).twitter();
timeAgoDep.changed(); // !!!
};
getTimeago(); /* Call it once so that we'll have an initial value */
timeAgoInterval = Meteor.setInterval(getTimeago, 5000);
};
Template.postItem.posted = function() {
timeAgoDep.depend(); // !!!
return timeAgo;
};
Template.postItem.destroyed = function() {
Meteor.clearInterval(timeAgoInterval);
};
I'm pretty sure that the problem comes from this.submitted because if I assign timeAgo = now for example, it will display the time and update like it's supposed to.
I also know that moment(this.submitted).twitter() works fine because when all I do is return it through a helper, it works.

A much better way to do this is to just embrace Meteor's reactivity and render time-dependent values reactively. In your case, the problem is that you are invalidating the dependency once every 5 seconds for each postItem rendered, which will quickly turn into a huge mess.
See https://github.com/mizzao/meteor-timesync for a package that provides reactive time variables on the client (and they are synced to server time too!) It's basically doing what you want, but in a cleaner way. (Disclaimer: I wrote this package.)
You can use moment in the same way to compute the actual string to display. For example, get rid of all the other stuff and just use
Template.postItem.posted = function() {
return moment(this.submitted).from(TimeSync.serverTime());
}
The moment().twitter() extension doesn't seem like a good choice because it only uses the current client time and doesn't allow you to pass in a specific (i.e. server-synced) time or reactive value.

AngularJS - how to handle circular watch?

Suppose I am working with a directive that is given a date in form of a unix timestamp via two-way binding, but also offers a calendar widget to change the selection.
The calendar widget works with a date object, and I am unable to change the input data format and I do not want to rework the calendar to support unix timestamp. Also this is just an example and the question is about general way of working with circular watchers.
The scope would look like this:
scope.selectedUnixTimestamp; // this comes from the outside
scope.selectedDate;
scope.$watch('selectedUnixTimestamp', function(newV, oldV) {
$scope.selectedDate = new Date(newV*1000);
});
scope.$watch('selectedDate', function(newV, oldV) {
$scope.selectedUnixTimestamp = Math.floor(newV.getTime()/1000 + 0.000001);
});
My question is: what do I do in order to avoid extra calls to $watch callbacks? Obviously if I choose a new date, the flow will be following:
Watcher #2 is called - it modifies selectedUnixTimestamp
Watcher #1 is called - it modifies selectedDate
Watcher #2 is called again (new object reference) - it modifies selectedUnixTimestamp
But I don't want any of those calls besides the first one. How do can I achieve it?
Obviously one way would be to do something like:
scope.selectedUnixTimestamp;
scope.selectedDate;
var surpressWatch1 = false;
var surpressWatch2 = false;
scope.$watch('selectedUnixTimestamp', function(newV, oldV) {
if(surpressWatch1) { surpressWatch1 = false; return; }
$scope.selectedDate = new Date(newV*1000);
surpressWatch2 = true;
});
scope.$watch('selectedDate', function(newV, oldV) {
if(surpressWatch2) { surpressWatch2 = false; return; }
$scope.selectedUnixTimestamp = Math.floor(newV.getTime()/1000 + 0.000001);
surpressWatch1 = true;
});
But it quickly becomes a hell to maintain a code like that.
Another way would be to do something like:
scope.selectedUnixTimestamp;
scope.selectedDate;
scope.$watch('selectedUnixTimestamp', function(newV, oldV) {
if(newV*1000 === scope.selectedDate.getTime()) { return; }
$scope.selectedDate = new Date(newV*1000);
});
scope.$watch('selectedDate', function(newV, oldV) {
if(scope.selectedUnixTimestamp*1000 === newV.getTime()) { return; }
$scope.selectedUnixTimestamp = Math.floor(newV.getTime()/1000 + 0.000001);
});
But it might be very costful if the data transformation is more complicated than * 1000
Another way would be to watch on primitive value instead of a date object:
scope.$watch('selectedDate.getTime()', function(newV, oldV) {
But this only works with this particular example and does not solve the general issue

How to work with circular watches? I guess answer is, try not to do it.
You can try this, although I am sure there are better solutions to your example.
Use only one watch function:
You can use a function as first parameter to the watch. This function will be called until the value it returns settles (is the same as last time). You can hence create a $watch like this:
$scope.$watch(function() {
return {
timestamp: scope.selectedUnixTimestamp,
date: scope.selectedDate
}
}, function(newVal, oldVal) {
// Note that newVal and oldVal here is on the form of the object you return in the watch function, and hence have properties: timestamp and date.
// You can compare newVal.date to oldVal.date (same with timestamp) to see which one has actually changed if you need to do that.
}
true); // You need a deep watch (the true param) to watch the properties on the object

The Angular framework is built on the following assumption:
The true and trustable value of something, ready to be synchronized with a REST service for example, exists once in the model.
Keeping this in mind, you never write circular watchers.
And in case you have two different ways to alter a model value, you would write directives requiring ngModelController instance and providing the right formatter and parser functions.

Alfresco Activiti script task listener current scriptnode?

Is there a way to get the ScriptNode that initiated a state in an Activiti workflow in Alfresco? I have a ScriptTask in my workflow, and it has a Alfresco Script Listener set up for the Start event. When the script is called, I'd like the ScriptNode that transitioned into the ScriptTask in the workflow to be passed as a parameter to the function defined as the listener. Is that possible?
Editing for clarity:
Here's a screenshot of Eclispe with the Activiti plugin.
http://i.imgur.com/DAKtq.jpg
This workflow gets started by another workflow with webscripts.
var props = new Object();
var dd = new Date();
props[EL_PROP_WORK_UNIT_NAME] = "testNode" + DateISOString( dd );
props[EL_PROP_WORK_UNIT_SOURCE_CODE] = "ROB";
props[EL_PROP_WORK_UNIT_DELIVERY_DATE] = dd;
node = getHome().createNode(name, EL_TYPE_WORK_UNIT, props);
var EL_WORKFLOW = "activiti$The-workflow";
var activeWfs = node.activeWorkflows;
if( activeWfs === null || activeWfs.length === 0 )
{
var workflowPackage = workflow.createPackage();
workflowPackage.addNode( node );
var workflowDef = workflow.getDefinitionByName(EL_WORKFLOW);
var workflowPath = workflowDef.startWorkflow( workflowPackage, new Object());
}
So the listener calls another javascript method...
function artPDFRename()
{
logger.log("==============================");
logger.log("<START> artPDFRename");
var workflowDef = workflow.getDefinitionByName(EL_WORKFLOW);
var activeInstance = workflowDef.getActiveInstances();
// ????
}
The goal is to have this handling be automatic. We're trying to design this with as little of manual intervention as possible, and are not assigning tasks to users to perform. Yes, there's probably another way to rename a PDF file, but I can't seem to figure out from the documentation listed here how to get a pointer to the node I put in the bpm_package object. That's the question.
Or am I so far off base on how we're developing this that it makes no sense?

As an example check the ScriptTaskListener class. Here all the workflow variables are put in a map.
The following code is interesting:
// Add all workflow variables to model
Map variables = delegateTask.getExecution().getVariables();
for (Entry<String, Object> varEntry : variables.entrySet())
{
scriptModel.put(varEntry.getKey(), varEntry.getValue());
}
So with this you could use bpm_package as an object within your script within the workflow script task.
So if you need the node were the workflow has run on, the following code should work (where task is your delegateTask from your notify method of the Listener:
delegateTask.getVariable("bpm_package");
// or like the example above
delegateTask.getExecution().getVariable("bpm_package");
This will be a list so take the first one and that will be your node.
---------update
If you're using the javascript from alfresco then you can directly use the parent object bpm_package.
So in your case it would be best to do the following:
var node = bpm_package.children[0]; //or you could check if the
package isn't null
// Then send the node into your
artPDFRename(node); //or you could just add the bpm_package code in
your js file