Introduction

SizeGripItem is a size grip QGraphicsItem for interactively resizing other QGraphicsItem objects. It draws a size grip with 8 interactive handles around its parent so that it can be interactively resized.

Installation

There is no installation procedure. To use SizeGripItem in your own project, just copy the SizeGripItem.h and SizeGripItem.cpp files and add them to your build.

Usage

SizeGripItem is designed to resize its parent item. You add a SizeGripItem to another QGraphicsItem simply by setting that item to be the SizeGripItem's parent.

When you create a new SizeGripItem, you must pass its constructor a pointer to an instance of a subclass of the SizeGripItem::Resizer class. SizeGripItem::Resizer is an abstract class with a pure virtual operator() with the following signature:

void operator()(QGraphicsItem* item, const QRectF& rect)

A subclass of SizeGripItem::Resizer must implement operator() with the signature above so that item is resized to fit rect when a call to the operator is made. rect corresponds to the rectangle described by the SizeGripItem's handles and its coordinates are in the SizeGripItem's coordinate system.

SizeGripItem instances take ownership of the SizeGripItem::Resizer pointer passed to them on construction, which means that pointer is deleted when the SizeGripItem is destroyed.

Example Code

The demo/ directory provides example code for using SizeGripItem. You can build and run the demo using CMake >=2.8.0 as follows (assuming you are at the project's root directory):

$ mkdir build
$ cd build
$ cmake ..
$ make
$ ./demo/sizegripitemdemo

License

SizeGripItem is under the MIT license. See LICENSE for details.