This project is one of my all time favourite projects. It was developed in my 5th semester and is the biggest of all my projects. It is about 6000 lines of C++ code. Its main features are that it is completely menu based although all menu choices have appropriate shortcuts. It has an inbuilt spell checking system. In the following sections I will discuss how these could be implemented.
Design Decisions
This is probably the most important part of any project. It decides the entire structure of your project. If your design is good not only will you be able to complete the project on time, moreover your code will be stable and reusable.
To start off, I decided I had to do my project in C++. There was one main reason that affected this decision. It was that C++ was object oriented which considerably reduces complexity of the project. Moreover the Standard Template Library
Next I decided on a data structure. I choose a list of lists as the data structure for the text editor. Though I don't remember why I chose it but I did definitely experiment with other data structures like a single list etc.. I will discuss the main classes in my editor in the following sections
The Menu Class
I had to choose between the menu library provided my ncurses or write my own. I chose the later as the library provided by ncurses did not satisfy my specific requirements. So I wrote a simple menu class that took in a list of strings as an argument, the number of strings, the x and y position of the menu as constructor arguments. Once this was done all I had to do was I had to call a method called GetChoice() which returned the selected number to me. I did not bother about saving the portion of the screen on which the menu was drawn as I could refresh the text below and the menu would disappear. It was much more simple than saving that portion of the screen in the memory and redrawing it back.
The File System Browser
As in any text editor I had a File system browser. This was again a simple class that displayed all the files in a directory. I used the up and down arrow keys for selection. It returned the name of the file that had been selected with the full path.
The Dialog Class
This class was used to display simple dialog boxes to display information and take input from users if there was a need for it.
The Data structure Class
The data structure was implemented as a class. The main reason for this was that I could have multiple instances of this class to edit multiple files. Thats how I implemented editing multiple files at once in different instances of the data structure class. This also had a display module. It had an interface which communicated with the spell checker class. All list manipulation was the work of this class. Whenever a key hit was detected by the interface and if the key was not a shortcut the keyhit() method of the data structure of the class was called which called the appropriate function.
The Spell Checker.
This is an absolutely brilliant class. I love it, because it was so simple. When somebody wanted the buffer spell checked the data structure created a new instance of the spell checker class. Then every line was converted from a C++ list to a simple C string and passed to the spell checker class that did the modification on the string and passed the modified string back. This was then updated in the data structure.
I used the pspell spell checker library for the spell checker engine.
Reading Material
I hope you are confortable with STL otherwise you can read Herbert Schiltd's - Complete C++ Reference
For starters on curses I suggest you start up by reading Pradeep Padala's - Ncurses Programming HOWTO.
I suggest you buy a copy of The Linux Programming Bible - John Goerzen. I find this an extremely useful and a well written book which covers nearly all aspects of programming in Linux.