Qt 4.8: QDesignerPropertyEditorInterface Class Reference

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# QDesignerPropertyEditorInterface Class Reference

The QDesignerPropertyEditorInterface class allows you to query and manipulate the current state of Qt Designer's property editor. More...

     #include <QDesignerPropertyEditorInterface>

Inherits: QWidget.

- List of all members, including inherited members

## Public Functions

| QDesignerPropertyEditorInterface ( QWidget * parent, Qt::WindowFlags flags = 0 )
virtual | ~QDesignerPropertyEditorInterface ()
virtual QDesignerFormEditorInterface * | core () const
virtual QString | currentPropertyName () const = 0
virtual bool | isReadOnly () const = 0
virtual QObject * | object () const = 0

- 221 public functions inherited from QWidget
- 29 public functions inherited from QObject
- 13 public functions inherited from QPaintDevice

## Public Slots

virtual void | setObject ( QObject * object ) = 0
virtual void | setPropertyValue ( const QString & name, const QVariant & value, bool changed = true ) = 0
virtual void | setReadOnly ( bool readOnly ) = 0

- 19 public slots inherited from QWidget
- 1 public slot inherited from QObject

## Signals

void | propertyChanged ( const QString & name, const QVariant & value )

- 1 signal inherited from QWidget
- 1 signal inherited from QObject

### Additional Inherited Members

- 58 properties inherited from QWidget
- 1 property inherited from QObject
- 4 static public members inherited from QWidget
- 7 static public members inherited from QObject
- 37 protected functions inherited from QWidget
- 8 protected functions inherited from QObject
- 1 protected function inherited from QPaintDevice
- 1 protected slot inherited from QWidget

## Detailed Description

The QDesignerPropertyEditorInterface class allows you to query and manipulate the current state of Qt Designer's property editor.

QDesignerPropertyEditorInterface contains a collection of functions that is typically used to query the property editor for its current state, and several slots manipulating it's state. The interface also provide a signal, propertyChanged(), which is emitted whenever a property changes in the property editor. The signal's arguments are the property that changed and its new value.

For example, when implementing a custom widget plugin, you can connect the signal to a custom slot:

             QDesignerPropertyEditorInterface *propertyEditor = 0;
             propertyEditor = formEditor->propertyEditor();

             connect(propertyEditor, SIGNAL(propertyChanged(QString, QVariant)),
                     this, SLOT(checkProperty(QString, QVariant)));

Then the custom slot can check if the new value is within the range we want when a specified property, belonging to a particular widget, changes:

             void checkProperty(QString property, QVariant value) {
                 QDesignerPropertyEditorInterface *propertyEditor = 0;
                 propertyEditor = formEditor->propertyEditor();

                 QObject *object = propertyeditor->object();
                 MyCustomWidget *widget = qobject_cast<MyCustomWidget>(object);

                 if (widget && property == aProperty && value != expectedValue)
                     {...}
             }

The QDesignerPropertyEditorInterface class is not intended to be instantiated directly. You can retrieve an interface to Qt Designer's property editor using the QDesignerFormEditorInterface::propertyEditor() function. A pointer to Qt Designer's current QDesignerFormEditorInterface object (`formEditor` in the examples above) is provided by the QDesignerCustomWidgetInterface::initialize() function's parameter. When implementing a custom widget plugin, you must subclass the QDesignerCustomWidgetInterface to expose your plugin to Qt Designer.

The functions accessing the property editor are the core() function that you can use to retrieve an interface to the form editor, the currentPropertyName() function that returns the name of the currently selected property in the property editor, the object() function that returns the currently selected object in Qt Designer's workspace, and the isReadOnly() function that returns true if the property editor is write proteced (otherwise false).

The slots manipulating the property editor's state are the setObject() slot that you can use to change the currently selected object in Qt Designer's workspace, the setPropertyValue() slot that changes the value of a given property and the setReadOnly() slot that control the write protection of the property editor.

See also QDesignerFormEditorInterface.

## Member Function Documentation

### QDesignerPropertyEditorInterface::QDesignerPropertyEditorInterface ( QWidget * parent, Qt::WindowFlags flags = 0 )

Constructs a property editor interface with the given parent and the specified window flags.

### QDesignerPropertyEditorInterface::~QDesignerPropertyEditorInterface ()`[virtual]`

Destroys the property editor interface.

### QDesignerFormEditorInterface * QDesignerPropertyEditorInterface::core () const`[virtual]`

Returns a pointer to Qt Designer's current QDesignerFormEditorInterface object.

### QString QDesignerPropertyEditorInterface::currentPropertyName () const`[pure virtual]`

Returns the name of the currently selected property in the property editor.

See also setPropertyValue().

### bool QDesignerPropertyEditorInterface::isReadOnly () const`[pure virtual]`

Returns true if the property editor is write protected; otherwise false.

See also setReadOnly().

### QObject * QDesignerPropertyEditorInterface::object () const`[pure virtual]`

Returns the currently selected object in Qt Designer's workspace.

See also setObject().

### void QDesignerPropertyEditorInterface::propertyChanged ( const QString & name, const QVariant & value )`[signal]`

This signal is emitted whenever a property changes in the property editor. The property that changed and its new value are specified by name and value respectively.

See also setPropertyValue().

### void QDesignerPropertyEditorInterface::setObject ( QObject * object )`[pure virtual slot]`

Changes the currently selected object in Qt Designer's workspace, to object.

See also object().

### void QDesignerPropertyEditorInterface::setPropertyValue ( const QString & name, const QVariant & value, bool changed = true )`[pure virtual slot]`

Sets the value of the property specified by name to value.

In addition, the property is marked as changed in the property editor, i.e. its value is different from the default value.

See also currentPropertyName() and propertyChanged().

### void QDesignerPropertyEditorInterface::setReadOnly ( bool readOnly )`[pure virtual slot]`

If readOnly is true, the property editor is made write protected; otherwise the write protection is removed.

See also isReadOnly().