CopperSpice Journal

A regular expression is a sequence of characters which defines a search pattern. It is used to search, extract, or replace text in an existing string. This example contains a few different ways to use the QRegularExpression class.

The QStringParser class provides a variety of methods to process strings of text. This example will show how to use split() and formatArg().

Although English is one of the most common languages, a well designed user interface should be shown using the language most appropriate for the user. CopperSpice provides built in support for text translations. This example will show how to switch between English and German text at run time by using an external translation file.

A GUI layout will typically contain multiple widgets which have a fixed position and a fixed size. The QSplitter class adds functionality for the user to modify the size of any child widgets, by dragging the boundary located between the controls.

This example shows how to create a resource file which contains a list of various file names which will be embedded in your application. When the executable is created the files listed in the resource file are bundled into the executable. The original files, which are now embedded, do not need to be distributed with the binary. The most common type of files include images, text, icons, and translation files.

The program for this example displays a plain TextEdit widget which contains source code. Portions of the text are highlighted in various colors using the GUI syntax highlighting class.

This example shows how to use low level drawing methods to create an ellipse, rounded rectangle, or a path shape and then set the pen to draw the border and the brush for the fill characteristics.

This example demonstrates how to use low level drawing methods to create a polygon shape and then set the pen to draw the border and the brush for the fill characteristics.

A common practice in a GUI application is the ability to press the tab key and move from one widget to another in some logical sequence. The tab ordering is initially set to mimic the order widgets are created. However, this might not match the tab order users expect. Let’s look at how we can create several widgets and then adjust the tab sequence, without rearranging the widget constructors.

A status message can be displayed on the bottom of a GUI main window. If the message is designated as “temporary” or only intended to be shown for a given time interval, it is displayed on the left side of the status bar. If the message is “permanent”, like showing the current line and column number in a document, this will be shown on the right side of the status bar and always visible.

The “What’s This” feature can be used to provide additional information about a menu option, push buttons or other widgets. This example adds “What’s This” help and also shows how to add a special question mark icon to a menu item and the tool bar for easy access to this feature.

A tool tip provides a hint or relevant additional information about the current object. In this example tool tips are added for several actions and the push buttons located on the central window. The hint will be displayed when the user hovers the mouse over the corresponding toolbar item or push button.

In this example a tool bar is added to a user application. A tool bar typically contains the most commonly used menu items. The same actions and icons used for the menu will be used on the tool bar.

This example will show how to create a user application which contains a top level menu. Adding a menu bar with icons and shortcuts is the next step in creating a graphical application.

This example uses a QTreeView with the QFileSystemModel to display the structure of a file system.