Wt

First of all I should note that I do not consider myself an expert in C (especially initializer lists).

I have found the initial steps to doing this but am having some problems. I am able to create a vector of instances of my node class and move each around using jquery, but now I want to update the positions of my arrows every time that one of my objects is moved.

In my constructor for a node, I have:

doJavascript("$('#"this->id)"').draggable();"); //set each node draggable

doJavascript("$('#"this->id)"').on('dragstop',Wt.emit($('#"this->id()"'),'newCoords',1,1));"); //call newCoords(,1,1) when movement stops

I have tested the first line, and tested the second line replacing "Wt.emit..." with alert and verified that it is calling my function when the object is moved. Now I want to use the new coordinates to update the locations of my arrows but I am having a lot of trouble with the JSignal class.

The first problem is that the Javascript example is a little bit simpler than what I am trying to do, and since I am not a C expert I am having a little bit of trouble generalizing. I have multiple parameters (int x and int y) that I would like to return from each node object and am having difficulty initializing my JSignal<int,int> in the initializer list.

Node::Node(WContainerWidget* parent):WContainerWidget(parent),newCoords_(this,"newCoords"){

...

doJavascript("$('#"this->id)"').draggable();");

doJavascript("$('#"this->id)"').on('dragstop',Wt.emit($('#"this->id()"'),'newCoords',1,1));");

...

}

The constructor for JSignal appears to only take a parent, a name (const char *) and a default false boolean (which I do not pass in) but then expects to initialize all parameters which gives me an error:

invalid reference of non-const reference of type 'Wt::JSignal<int,int>&' from an rvalue of type 'const char*'

Am I even approaching the JSignal correctly? I am just trying to return 2 positions (x and y) to the individual (c) object that was moved in javascript.

Nevermind, I have fixed the problem, I had an & that I did not need. It still does not return the values to me though.

Hey,

Your code does look like it should work, at least the logic seems correct. What values do you get in the signal handler server-side?

Regards,

koen

It does work now, my code to call the Wt.emit was not correct.

doJavascript("$('#"this->id)"').on('dragstop',function(event,ui){Wt.emit($('#"this->id()"'),'newCoords',1,1))};");

I overlooked wrapping my function when I removed my alert.