QDesignerWidgetBoxInterface Class

Detailed Description

QDesignerWidgetBoxInterface contains a collection of functions that is typically used to manipulate the contents of Qt Widgets Designer's widget box.

Qt Widgets Designer uses an XML file to populate its widget box. The name of that file is one of the widget box's properties, and you can retrieve it using the fileName() function.

QDesignerWidgetBoxInterface also provides the save() function that saves the contents of the widget box in the file specified by the widget box's file name property. If you have made changes to the widget box, for example by dropping a widget into the widget box, without calling the save() function, the original content can be restored by a simple invocation of the load() function:

        auto *widgetBox = formEditor->widgetBox();

        widgetBox->load();

The QDesignerWidgetBoxInterface class is not intended to be instantiated directly. You can retrieve an interface to Qt Designer's widget box using the QDesignerFormEditorInterface::widgetBox() function. A pointer to Qt Widgets Designer's current QDesignerFormEditorInterface object (formEditor in the example 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 Widgets Designer.

If you want to save your changes, and at the same time preserve the original contents, you can use the save() function combined with the setFileName() function to save your changes into another file. Remember to store the name of the original file first:

        QString originalFile = widgetBox->fileName();

        widgetBox->setFileName("myWidgetBox.xml");
        widgetBox->save();

Then you can restore the original contents of the widget box by resetting the file name to the original file and calling load():

        widgetBox->setFileName(originalFile);
        widgetBox->load();

In a similar way, you can later use your customized XML file:

        if (widgetBox->filename() != "myWidgetBox.xml") {
            widgetBox->setFileName("myWidgetBox.xml");
            widgetBox->load();
        }