QRemoteObjectReplica Class

A class interacting with (but not implementing) a Qt API on the Remote Object network. More...

Header:	#include <QRemoteObjectReplica>
qmake:	QT += remoteobjects
Inherits:	QObject
Inherited By:	QRemoteObjectDynamicReplica and QRemoteObjectRegistry

List of all members, including inherited members

Public Types

enum	State { Uninitialized, Default, Valid, Suspect, SignatureMismatch }

Properties

node : QRemoteObjectNode*
state : const State

Public Functions

QRemoteObjectNode *	node() const
virtual void	setNode(QRemoteObjectNode *node)
QRemoteObjectReplica::State	state() const

Signals

void	stateChanged(QRemoteObjectReplica::State state, QRemoteObjectReplica::State oldState)

Detailed Description

A Remote Object Replica is a QObject proxy for another QObject (called the Source object). Once initialized, a replica can be considered a "latent copy" of the Source object. That is, every change to a Q_PROPERTY on the Source, or signal emitted by the Source will be updated/emitted by all Replica objects. Latency is introduced by process scheduling by any OSes involved and network communication latency. As long as the replica has been initialized and the communication is not disrupted, receipt and order of changes is guaranteed.

The isInitialized and state properties (and corresponding initialized()/stateChanged() signals) allow the state of a Replica to be determined.

While Qt Remote Objects (QtRO) handles the initialization and synchronization of Replica objects, there are numerous steps happening behind the scenes which can fail and that aren't encountered in single process Qt applications. See Troubleshooting for advice on how to handle such issues when using a remote objects network.

Member Type Documentation

enum QRemoteObjectReplica::State

This enum type specifies the various state codes associated with QRemoteObjectReplica states:

Constant	Value	Description
`QRemoteObjectReplica::Uninitialized`	`0`	initial value of DynamicReplica, where nothing is known about the replica before connection to source.
`QRemoteObjectReplica::Default`	`1`	initial value of static replica, where any defaults set in the .rep file are available so it can be used if necessary.
`QRemoteObjectReplica::Valid`	`2`	indicates the replica is connected, has good property values and can be interacted with.
`QRemoteObjectReplica::Suspect`	`3`	error state that occurs if the connection to the source is lost after it is initialized.
`QRemoteObjectReplica::SignatureMismatch`	`4`	error state that occurs if a connection to the source is made, but the source and replica are not derived from the same .rep (only possible for static Replicas).

Property Documentation

node : QRemoteObjectNode*

This property holds a pointer to the node this object was acquired from.

Access functions:

QRemoteObjectNode *	node() const
virtual void	setNode(QRemoteObjectNode *node)

state : const State

Returns the replica state.

This property holds the replica QRemoteObjectReplica::State.