Class wtObject

Object
   |
   +--wtObject

Direct Known Subclasses:

wtWindowManager, wtWidget, wtVectorView, wtInput, wtVectorWidget, wtForm, wtGraphVertex, wtNotebookPage, _wtAsyncRPC, wtGraph

class wtObject

wtObject is the base class of most other classes in WT Toolkit. It simulates weak references and a proxy pattern such that memory-expensive objects (e.g. DOM nodes) can be referenced from other objects via a very cheap object. This helps mitigate the lapsed listener problem and avoids circular referencing memory leaks in Internet Explorer 6.
Defined in wt_core.js

Constructor Detail

wtObject

wtObject()

Constructs a wtObject

addDependency

void addDependency(<wtObject> obj)

Assigns a dependency relation to this object for garbage collection purpose.

Parameters:
obj - The wtObject this object is dependent upon. If obj is garbage collected then this object would be garbage collected as wel.

clearLapsedListeners

void clearLapsedListeners()

Clears all lapsed event listeners attached to this object.

connect

void connect(<String> connId, <String> signalName, <wtObject> target, <String> slotName)

Connects a signal to a slot.

Signals of a wtObject are defined via the setSignal() operation.
Slots of a wtObject are defined via the setSlot() operation.
Slots are named function objects stored under a wtObject's weakly referenced image.

All slot function objects have a common argument format:
slotFunction(target, evt, source)

Where target is the object holding the slot function, source is the object receiving the event, and evt is the event-specific argument object.

Parameters:
connId - The signal-slot connection ID, this ID can be used later to disconnect a signal from a slot. Each signal-slot connection ID should be unique for the same signal source and signal name.
signalName - The signal name.
target - The target to deliever the event information to.
slotName - The slot name.

See:
- setSignal()
- setSlot()
- emit()
- disconnect()

disconnect

void disconnect(<String> connId, <String> signalName)

Disconnects a signal from a slot.

Parameters:
connId - The signal-slot connection ID
signalName - The signal name

emit

void emit(<String> signalName, <Object> evt)

Emits a signal with an event argument.

Parameters:
signalName - Signal name to be emitted.
evt - Event argument object.

endProxy

void endProxy()

Disconnects the weak reference and removes the memory expensive object from the weak reference table.

get

Object get(<String> name)

Tells the value of an attribute under the weakly referenced image.

Parameters:
name - The attribute name

Returns:
The attribute value

removeSignal

void removeSignal(<String> signalName)

Removes a named signl

Parameters:
signalName - The signal's name

removeSlot

void removeSlot(<String> slotName)

Removes a named slot

Parameters:
slotName - The slot's name

set

void set(<String> name, <Object> value)

Sets an attribute value under the weakly referenced image.

Parameters:
name - The attribute name
value - The attribute value

setSignal

void setSignal(<String> signalName)

Creates a named signal

Parameters:
signalName - The signal's name

setSlot

void setSlot(<String> slotName, <Function> func)

Assigned an event handler function to a named slot.

Parameters:
slotName - The slot's name
func - The event handler function

startProxy

void startProxy(<String> obj, <String> id)

Establishes a weak reference link to a memory expensive object.

Parameters:
obj - The memory expensive object.
id - (Optional) The ID of the weak reference. Leave this empty if you don't know what you're doing.

toString

String toString()

Tells the string ID of the weak reference.

Returns:
String ID of weak reference.