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hedera-web-mindshore/js/vn/object.js

243 lines
4.6 KiB
JavaScript

/**
* The main base class. Manages the signal system.
*
* @param signals Map with all connected signal handlers
*/
module.exports = new Class
({
Tag: 'vn-object'
,Properties: {}
,_refCount: 1
,_signalData: null
,initialize: function (props)
{
this.setProperties (props);
}
/**
* Sets a group of object properties.
*
* @param {Object} props Properties
*/
,setProperties: function (props)
{
for (var prop in props)
this[prop] = props[prop];
}
/**
* Increases the object reference count.
*/
,ref: function ()
{
this._refCount++;
return this;
}
/**
* Decreases the object reference count.
*/
,unref: function ()
{
this._refCount--;
if (this._refCount === 0)
this._destroy ();
}
,loadXml: function (builder, node) {}
,appendChild: function (child) {}
,_signalInit: function ()
{
if (!this._signalData)
this._signalData = {
signals: {},
links: {}
};
}
/**
* Conects a signal with a function.
*
* @param {String} id The signal identifier
* @param {Function} callback The callback
* @param {Object} instance The instance
*/
,on: function (id, callback, instance)
{
if (!(callback instanceof Function))
{
console.warn ('Vn.Object: Invalid callback for signal \'%s\'', id);
return;
}
this._signalInit ();
var callbacks = this._signalData.signals[id];
if (!callbacks)
callbacks = this._signalData.signals[id] = [];
callbacks.push
({
blocked: false
,callback: callback
,instance: instance
});
}
/**
* Locks/Unlocks a signal emission to the specified object.
*
* @param {String} id The signal identifier
* @param {Function} callback The callback
* @param {Boolean} block %true for lock the signal, %false for unlock
*/
,blockSignal: function (id, callback, block, instance)
{
if (!this._signalData)
return;
var callbacks = this._signalData.signals[id];
if (!callbacks)
return;
for (var i = 0; i < callbacks.length; i++)
if (callbacks[i].callback == callback
&& callbacks[i].instance == instance)
callbacks[i].blocked = block;
}
/**
* Emits a signal in the current object.
*
* @param {String} id The signal identifier
*/
,signalEmit: function (id)
{
if (!this._signalData)
return;
var callbacks = this._signalData.signals[id];
if (!callbacks)
return;
var callbackArgs = [];
callbackArgs.push (this);
for (var i = 1; i < arguments.length; i++)
callbackArgs.push (arguments[i]);
for (var i = 0; i < callbacks.length; i++)
if (!callbacks[i].blocked)
callbacks[i].callback.apply (callbacks[i].instance, callbackArgs);
}
/**
* Disconnects a signal from current object.
*
* @param {String} id The signal identifier
* @param {Function} callback The connected callback
* @param {Object} instance The instance
*/
,disconnect: function (id, callback, instance)
{
if (!this._signalData)
return;
var callbacks = this._signalData.signals[id];
if (!callbacks)
return;
for (var i = 0; i < callbacks.length; i++)
if (callbacks[i].callback === callback
&& callbacks[i].instance === instance)
callbacks.splice (i--, 1);
}
/**
* Disconnects all signals for the given instance.
*
* @param {Object} instance The instance
*/
,disconnectByInstance: function (instance)
{
if (!this._signalData)
return;
var signals = this._signalData.signals;
for (var signalId in signals)
{
var callbacks = signals[signalId];
for (var i = 0; i < callbacks.length; i++)
if (callbacks[i].instance === instance)
callbacks.splice (i--, 1);
}
}
/**
* Destroys the object, this method should only be called before losing
* the last reference to the object.
*/
,_destroy: function ()
{
if (!this._signalData)
return;
var links = this._signalData.links;
for (var key in links)
this._unlink (links[key]);
this._signalData = null;
}
,_unlink: function (object)
{
object.disconnectByInstance (this);
object.unref ();
}
/**
* Links the object with another object.
*
* @param {Object} prop The linked property
* @param {Object} handlers The object events to listen with
*/
,link: function (prop, handlers)
{
this._signalInit ();
var links = this._signalData.links;
for (var key in prop)
{
var newObject = prop[key];
var oldObject = this[key];
if (oldObject)
this._unlink (oldObject);
this[key] = newObject;
if (newObject)
{
links[key] = newObject.ref ();
for (var signal in handlers)
newObject.on (signal, handlers[signal], this);
}
else if (oldObject)
delete links[key];
}
}
});