Multiple Inheritance in Qt

Introduction

A quick trivia quiz:

  1. Does Qt use multiple inheritance?
  2. If so, how many public Qt classes use it?
  3. Does any Qt class directly inherit from more than two classes?
  4. Does Qt let you multiply inherit (directly or indirectly) from QObject?

If you can correctly answer these questions off the top of your head you're definitely a Qt and C++ guru and can stop reading now. If not, then by the end of this article you will be able to answer these questions and impress your colleagues with your knowledge.

What's New in Qt 5: QMimeDatabase and QMimeType

QMimeDatabase and QMimeType are new classes introduced in Qt 5. MIME, which stands for Multipurpose Internet Mail Extensions, is an Internet standard for identifying file formats. The MIME standard was originally created to support attachment of files in e-mail messages. A good reference for MIME can be found here.

The QMimeDatabase class returns information about the database of MIME types on a system. Instances of the QMimeType class describe the type of a file or data.

What's New in Qt 5: The QScreen Class

QScreen is a new class introduced in Qt 5.0.0 that returns information about screen properties, where screen here refers to a display, such as a monitor or LCD panel.

[Update: It was pointed out that Qt 4 has a class named QScreen. However, the QScreenclass in Qt 4 was entirely different from the one in Qt 5 with different APIs and used for a different purpose. So I really consider them to be different classes.]

PhoneGap for Qt 5 Project Kickoff

This week we kicked off the PhoneGap for Qt 5 project. The goal of the project is to develop a complete version of the PhoneGap open source mobile development framework for the Qt 5 platform.

A Week of Compiling

This week was a little slow as some people were away for the holidays. The new callback-qtimplementation by Viras got committed to github and we are now working with that version.

Another Name Change

PhoneGap, recently renamed to Apache Callback, is now being renamed as Apache Cordova.

Marketing Push

This week we did some marketing to promote the project. All of this effort stimulated some good discussion on the blogs and callback developer mailing list.

New Qt 5 / WebKit 2 WebView APIs

There was no blog posting last week because I was away for some vacation in a warm place.

This week work continued implementing the APIs for Accelerometer and Notification and using the Qt Simulator for testing.

Repos Moving

This week we finished implementing some Cordova APIs (at least for the Qt 4 version). Compass and Accelerometer are done and some of Events was implemented. Notification is done as is most of File support and we are starting work on Contacts and Camera.

Note that I am going to start consistently using the name Cordova rather than Callback orPhoneGap for this project.