Qt Jambi Home

com.trolltech.qt.core
Class QSignalMapper

java.lang.Object
  extended by com.trolltech.qt.QSignalEmitter
      extended by com.trolltech.qt.QtJambiObject
          extended by com.trolltech.qt.core.QObject
              extended by com.trolltech.qt.core.QSignalMapper
All Implemented Interfaces:
QtJambiInterface
Direct Known Subclasses:
QGuiSignalMapper

public class QSignalMapper
extends QObject

The QSignalMapper class bundles signals from identifiable senders.

This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal.

The class supports the mapping of particular strings or integers with particular objects using setMapping. The objects' signals can then be connected to the map slot which will emit the mapped() signal with the string or integer associated with the original signalling object. Mappings can be removed later using removeMappings.

Example: Suppose we want to create a custom widget that contains a group of buttons (like a tool palette). One approach is to connect each button's clicked() signal to its own custom slot; but in this example we want to connect all the buttons to a single slot and parameterize the slot by the button that was clicked.

Here's the definition of a simple custom widget that has a single signal, clicked(), which is emitted with the text of the button that was clicked:

    class ButtonWidget : public QWidget
    {
        Q_OBJECT

    public:
        ButtonWidget(QStringList texts, QWidget *parent = 0);

    signals:
        void clicked(const QString &text);

    private:
        QSignalMapper *signalMapper;
    };

The only function that we need to implement is the constructor:

    ButtonWidget::ButtonWidget(QStringList texts, QWidget *parent)
        : QWidget(parent)
    {
        signalMapper = new QSignalMapper(this);

        QGridLayout *gridLayout = new QGridLayout;
        for (int i = 0; i < texts.size(); ++i) {
            QPushButton *button = new QPushButton(texts[i]);
            connect(button, SIGNAL(clicked()), signalMapper, SLOT(map()));
            signalMapper->setMapping(button, texts[i]);
            gridLayout->addWidget(button, i / 3, i % 3);
        }

        connect(signalMapper, SIGNAL(mapped(const QString &)),
                this, SIGNAL(clicked(const QString &)));

        setLayout(gridLayout);
    }

A list of texts is passed to the constructor. A signal mapper is constructed and for each text in the list a QPushButton is created. We connect each button's clicked() signal to the signal mapper's map slot, and create a mapping in the signal mapper from each button to the button's text. Finally we connect the signal mapper's mapped() signal to the custom widget's clicked() signal. When the user clicks a button, the custom widget will emit a single clicked() signal whose argument is the text of the button the user clicked.

See Also:
QObject, QButtonGroup, QActionGroup

Nested Class Summary
 
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.AbstractSignal, QSignalEmitter.Signal0, QSignalEmitter.Signal1<A>, QSignalEmitter.Signal2<A,B>, QSignalEmitter.Signal3<A,B,C>, QSignalEmitter.Signal4<A,B,C,D>, QSignalEmitter.Signal5<A,B,C,D,E>, QSignalEmitter.Signal6<A,B,C,D,E,F>, QSignalEmitter.Signal7<A,B,C,D,E,F,G>, QSignalEmitter.Signal8<A,B,C,D,E,F,G,H>, QSignalEmitter.Signal9<A,B,C,D,E,F,G,H,I>
 
Field Summary
 QSignalEmitter.Signal1<java.lang.Integer> mappedInteger
          This signal is emitted when map is signalled from an object that has an integer mapping set.
 QSignalEmitter.Signal1<QObject> mappedQObject
          This signal is emitted when map is signalled from an object that has an object mapping set.
 QSignalEmitter.Signal1<QWidget> mappedQWidget
          Deprecated. 
 QSignalEmitter.Signal1<java.lang.String> mappedString
          This signal is emitted when map is signalled from an object that has a string mapping set.
 
Constructor Summary
QSignalMapper()
          Equivalent to QSignalMapper(0).
QSignalMapper(QObject parent)
          Constructs a QSignalMapper with parent parent.
 
Method Summary
static QSignalMapper fromNativePointer(QNativePointer nativePointer)
          This function returns the QSignalMapper instance pointed to by nativePointer
 void map()
          This slot emits signals based on which object sends signals to it.
 void map(QObject sender)
          This slot emits signals based on the sender object.
 QObject mapping(int id)
          Returns the sender QObject that is associated with the given id.
 QObject mapping(QObject object)
          Returns the sender QObject that is associated with the given object.
 QObject mapping(QWidget widget)
          Deprecated. 
 QObject mapping(java.lang.String text)
          Returns the signal sender associated with the string text.
 void removeMappings(QObject sender)
          Removes all mappings for sender.
 void setMapping(QObject sender, int id)
          Adds a mapping so that when map is signalled from the given sender, the signal mapped(id) is emitted.
 void setMapping(QObject sender, QObject object)
          Adds a mapping so that when map is signalled from the given sender, the signal mapped(object ) is emitted.
 void setMapping(QObject sender, QWidget widget)
          Deprecated. 
 void setMapping(QObject sender, java.lang.String text)
          Adds a mapping so that when map is signalled from the given sender, the signal mapped(text ) is emitted.
 
Methods inherited from class com.trolltech.qt.core.QObject
blockSignals, childEvent, children, connectSlotsByName, customEvent, disposeLater, dumpObjectInfo, dumpObjectTree, dynamicPropertyNames, event, eventFilter, findChild, findChild, findChild, findChildren, findChildren, findChildren, findChildren, installEventFilter, isWidgetType, killTimer, moveToThread, objectName, parent, property, removeEventFilter, setObjectName, setParent, setProperty, signalsBlocked, startTimer, thread, timerEvent
 
Methods inherited from class com.trolltech.qt.QtJambiObject
dispose, disposed, finalize, reassignNativeResources, tr, tr, tr
 
Methods inherited from class com.trolltech.qt.QSignalEmitter
disconnect, disconnect, signalSender
 
Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface com.trolltech.qt.QtJambiInterface
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership
 

Field Detail

mappedQWidget

@Deprecated
public final QSignalEmitter.Signal1<QWidget> mappedQWidget
Deprecated. 

mappedString

public final QSignalEmitter.Signal1<java.lang.String> mappedString

This signal is emitted when map is signalled from an object that has a string mapping set. The object's mapped string is passed in arg__1.

Compatible Slot Signatures:
void mySlot(java.lang.String arg__1)
void mySlot()
See Also:
setMapping


mappedInteger

public final QSignalEmitter.Signal1<java.lang.Integer> mappedInteger

This signal is emitted when map is signalled from an object that has an integer mapping set. The object's mapped integer is passed in arg__1.

Compatible Slot Signatures:
void mySlot(int arg__1)
void mySlot()
See Also:
setMapping


mappedQObject

public final QSignalEmitter.Signal1<QObject> mappedQObject

This signal is emitted when map is signalled from an object that has an object mapping set. The object provided by the map is passed in arg__1.

Compatible Slot Signatures:
void mySlot(com.trolltech.qt.core.QObject arg__1)
void mySlot()
See Also:
setMapping

Constructor Detail

QSignalMapper

public QSignalMapper()

Equivalent to QSignalMapper(0).


QSignalMapper

public QSignalMapper(QObject parent)

Constructs a QSignalMapper with parent parent.

Method Detail

map

public final void map(QObject sender)

This slot emits signals based on the sender object.


map

public final void map()

This slot emits signals based on which object sends signals to it.


mapping

public final QObject mapping(int id)

Returns the sender QObject that is associated with the given id.

See Also:
setMapping

mapping

public final QObject mapping(QObject object)

Returns the sender QObject that is associated with the given object.


mapping

public final QObject mapping(java.lang.String text)
Returns the signal sender associated with the string text.


removeMappings

public final void removeMappings(QObject sender)

Removes all mappings for sender.

This is done automatically when mapped objects are destroyed.


setMapping

public final void setMapping(QObject sender,
                             java.lang.String text)

Adds a mapping so that when map is signalled from the given sender, the signal mapped(text ) is emitted.

There may be at most one text for each sender.


setMapping

public final void setMapping(QObject sender,
                             QObject object)

Adds a mapping so that when map is signalled from the given sender, the signal mapped(object ) is emitted.

There may be at most one object for each sender.

See Also:
mapping

setMapping

public final void setMapping(QObject sender,
                             int id)

Adds a mapping so that when map is signalled from the given sender, the signal mapped(id) is emitted.

There may be at most one integer ID for each sender.

See Also:
mapping

fromNativePointer

public static QSignalMapper fromNativePointer(QNativePointer nativePointer)
This function returns the QSignalMapper instance pointed to by nativePointer

Parameters:
nativePointer - the QNativePointer of which object should be returned.

mapping

@Deprecated
public QObject mapping(QWidget widget)
Deprecated. 

This method has been deprecated. Use com.trolltech.qt.gui.QGuiSignalMapper.mapping() instead.


setMapping

@Deprecated
public void setMapping(QObject sender,
                                  QWidget widget)
Deprecated. 

This method has been deprecated. Use com.trolltech.qt.gui.QGuiSignalMapper.setMapping() instead.


Qt Jambi Home