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.

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.