Many people mistakenly think that shell scripts can only be run in command line. In fact shell can also call some GUI components such as menus,alert dialogs, progress bar etc. You can control the final output, cursor position and various output effects. Here we introduce some tools which can help you create powerful, interactive and user friendly Unix/Linux shell scripts.1. notify-sendThis command can let you inform the process to send a desktop notification to users. This can be used to send prompt to users or display some information to users. You can download it :$ sudo apt-get install libn...

Qt framework is a popular C++GUI framework developed by Nokia. And it is also cross platform compatible. Manydevelopers are using Qt to develop C++ GUI programs. In Qt, some importantcomponents are deserved our close attention. Many developers faced the problemwhen they put some widgets in a QScrollArea widget and they want it to displayscroll bars when the widgets inside the QScrollArea overflows. After manyexperiments, I propose a way which can show scroll bars as you expected. The relationship betweenwidgets and layout is the key here. Generally, we need not to add layout toscroll area dire...

Books on parallel programming theory often talk about such weird beasts like the PRAM model, a hypothetical hardware that would provide the programmer with a number of processors that is proportional to the input size of the problem at hand. Modern general purpose computers afford only a few processing units; four is currently a reasonable number. This limitation makes the development of highly parallel applications quite difficult to the average computer user. However, the low cost and the increasing programmability of graphics processing units, popularly know as GPUs, is contributing to over...

Consider this user interface for a car:The goal of these interfaces is to make you operate something, and operate it efficiently and safely. The grooves and clicks and limits constrain the range of motion and the number of choices. The visual look heavily hints at how to actively use it. They are usually not hard to learn. More importantly, the learning curve plateaus. Once you learn how to drive a car, there’s not much progression after that. Boundedness is an important property of these interfaces, by design.Now look at this “user interface” f...