GUI – Icons and Tool Bar

Now that the resource mechanism has been added to the project, actions can now be added to the tool bar with appropriate icons.  Contrary to what was said at the beginning of the last post, tool bar items can be text and are text if no icon has been assigned to them.  In any case, icons will be used here for the tool bar.  Also, when an action has an assigned icon, the icon also appears on the menu item in the menus.

First icons need to be assigned to the actions.  The easiest way to do this is with Designer inside QtCreator.  The icons can be assigned the same as with the MainWindow object, but it is easier to add the icons from the Action Editor tab at the bottom of Designer.  Double-clicking on the action brings up the Edit Action dialog.  The icon is added by clicking the ... button on the Icon: field line.  Appropriate icons were added to all of the actions.  To add the actions to the tool bar, the actions are simply dragged from the Action Editor to the tool bar.

Note: The icons will not be available on the Select Resource dialog until the program has been built after the icons have been added to the resource file.

The icons were obtained from the KDE Oxygen icon set (found in the /usr/share/icons/oxygen/32x32/actions/ directory on Linux) except for the Qt icon, which was obtained from the Qt SDK.  All of the icon file names were renamed to match the menu and menu item the icon was assigned to.  The Oxygen icons can be distributed with the source code and embedded within the program as long as the program is under the LGPL (Lesser GNU Pulbic License) version 3, which this program is being developed under.

[commit a2d2675627]

GUI – Icons and Resources

The next item for the GUI is to add items to the tool bar, which has already been created, but is currently only blank.  Unlike the menu items which are text, the tool bar items are icons.  It is convenient if the icons are part of the application file and not separate files that must be included to run and must be loaded by the application.

This is accomplished by converting the icon files into C++ source files that are then compiled and linked into the application.  The Qt Resource Compiler (RCC) is used to convert the icon files to source files.  All the resources for the program are listed in an XML resource (.qrc) file.  QtCreator makes it easy to create and maintain these resource files.

To create the resource file, the new file wizard was again utilized.  Under Files and Classes the Qt item (lower-left) and Qt Resource file (upper-right) was selected.  On the next Choose the Location dialog, the Name: field was set to ibcp.qrc.  On the next Project Management dialog, the defaults were selected (which was set to git).  Once finished, QtCreator opened up a specific resources editing window.

To start simple, an application icon was given to the program, which will appear in the upper corner of the application window and on the task bar of the OS.  Up to now, a generic icon was being used (an X icon on Linux/KDE and a generic program icon on Windows).  An icon file was created by the name ibcp.png and placed in the new images sub-directory.  The image chosen and created consists of two lightning bolts, which represents the letter I, two to represent Interactive and Incremental, for the type of BASIC compiler being created.  The lightning bolt itself represents speed, since the goal of this project is to make a fast interactive BASIC compiler.

To add this new icon to the resource file, the Add button at the bottom resource editing window was clicked and Add Prefix was selected.  The Prefix: field, which defaulted to /new/prefix1 was cleared (which set it to a single slash).  The Add/Add Files was then selected, which opened a file selection dialog.  The images/ibcp.png file was selected, which added the file to the resource list.

To assign this icon file to the application, in Designer, the MainWindow object was selected (upper-right panel) and under properties (lower-right panel), the ... button was clicked for the windowIcon property, which displayed a Select Resource dialog.  The images item (left-side) was selected, which displayed the ibcp.png icon (right-side), which was selected.

To finish, the building of the resources needed to be added to the CMake build file.  Resources are handled by the qt4_add_resources command that is added as part of the Qt4 CMake module.  This command is given a list of resource files (in this case ibcp.qrc) and produces a list of resource source files that are generated by RCC.  This list of generated source files was then added to the add_executable command.

[commit ba9ee1be2a]

GUI – Status Bar

The status bar on the bottom of the window was already automatically created when the MainWindow class was created from the new file wizard and is already being used for the menu item status tips.  Eventually program information like current line and column will be displayed on the status line along with error messages.  But for now there are a few places where messages are needed for the file operation functions, specifically when the program has been loaded or saved successfully.

[commit ea1b7585bb]

GUI – File Operations - Functions

A couple of helper functions were implemented to support the file operation functions.  The first is a function check if it is okay to continue, which checks if the file has been modified and if it has, ask if the file should be saved or the operation canceled.  This check is needed on the new, open and close program functions.

The second helper function sets a new member variable that holds the current program file path and sets the window title to the base file name of the current program file path.  The window title is set to the string "<file name>[*] ‑ IBCP" where the [*] is a placeholder for whether the file has been modified.  Qt handles this in a platform specific way.  Qt handles this in a platform specific way.  Generally on Windows and Linux, it  simple puts an asterisk after the file name, but on MAC, a dot is put in the close bubble.  If the program file path is blank, the program name is set to the "Untitled" string.

In the main window constructor, a connection was added to the edit box document's modification changed signal to the main windows set window modified slot.  Whenever the document is modified, this signal causes the file modified indicator to appear.

Two support functions were also implemented that load and save the program into or from memory, though right now they simply read and write a text file to or from the edit box document as plain text.  Eventually when a program is loaded, it will need to be parsed, translated, encoded and stored in memory.  Details of the main file operation functions can be found by clicking Continue...

[commit ea1b7585bb]

Actions/Menus – Using Designer

I discovered a much better and easier way to create actions and menus for the application without having to write all the lines of code by using Designer within QtCreator.  The UI form for the main window is opened in Designer by double-clicking on mainwindow.ui from the project files area.

Main menus are added by double-clicking on the "Type Here" text at the top of the edit area and entering the text.  Hot keys are entered by preceding the desired character with an '&' ampersand character.  The menus can be repositioned by dragging them as desired.

Menu items are added is a similar way, by selecting the main menu and again double-clicking the "Type Here" text.  Separators are added by double-clicking the "Add Separator" text.  Status tips are entered in the statusTip field on the lower-right side properties after selecting the desired action from the upper-right side object tree list.  Shortcut keys can be entered in the shortcut field in the properties area or can be entered using the Action Editor tab at the bottom of Designer.

Designer automatically names the actions with the name "actionXxx" where Xxx is the text entered for the menu item.  The under-bar character is used for spaces, so these were removed to follow the camel casing naming convention.  Qt will make connections between actions and functions automatically if the functions are named correctly.  For the menu item actions, the functions are named on_actionXxx_triggered() where actionXxx is the name of the action and triggered is the name of the signal to connect.  All of the dummy program functions were renamed to this form so that the needed connections are made automatically.

However, this does not work for connecting the actionExit triggered signal to the MainWindow::close() function, since this does not follow the automatic naming convention.  This was accomplished by using Signal & Slots Editor tab at the bottom of Designer.  A new signal/slot is added by clicking the large plus icon.  For this new entry, the Sender was set to actionExit, the Signal was set to triggered(), the Receiver was set to MainWindow, and the Slot was set to close().

The actionAboutQt action could not be setup in Designer since there is no way to connect to the application's aboutQt() function using the Signal & Slots Editor because the application object is not an available Receiver.  This was instead accomplished by adding a new on_actionAboutQt_triggered() function to MainWindow, which simply calls qApp‑>aboutQt().

Now that all the actions and menus are in the UI form for MainWindow, the action enumeration, action pointers and menu pointers were removed from the class definition.  The pointers are now contained in the Ui::MainWindow class that is automatically generated from the mainwindow.ui form file by the UIC (Qt User-Interface Compiler), which MainWindow contains a member pointer to.  Since the setupUi() function, called in the constructor, now creates the actions and sets up the menus, the createActions() and createMenus() functions are no longer needed and were removed.

[commit 46737de13d]

GUI – File Operations - Actions

To start, the EditBox will be made to handle simple text files.  Once the base GUI functionality is implemented, the process of implementing a full program editor will commence .  The first file operations to implement are new, open, save, and save as.

To create an action, several lines of code are needed, plus there needs to be a QAction pointer added to the class definition for each.  The program is going to end up with a lot of actions, so a more streamlined way of handling actions was needed.

In the MainWindow class definition, an enumeration for all actions was added.  Values will be added to this enumeration for each new action implemented.  The enumeration ends with a size of value, which is used to declare an array of QAction pointers.

In the createActions() function, a simple action information structure was added containing the action enumeration value, the name, the shortcut key sequence and the status tip string of the action.  An array of these action information structures is declared and initialized.  The size of enumeration value in the action value is used to indicate the end of the array.

A loop was added to process each element in this array, creating the QAction instance, setting its shortcut key sequence and status tip.  Not all actions will have a shortcut key sequence, so for these, the key sequence is initialized to an unknown value and no key sequence will not be set for these.

Finally all the actions are connected to their associated functions.  Unfortunately, the connection call could not be included in the loop because of the Qt SIGNAL and SLOT macros and the inability to declare a function pointer that could be added to the information array.  Plus, not all connection calls are identical (the close function returns a boolean instead of nothing and the About Qt action is connected to an application function, not a MainWindow function).  For now only dummy file operation functions were added - these will be implemented next.

[commit 8958bacc2e]

GUI – Edit Box (Begin)

To create the new EditBox class source and header file, the new file wizard of QtCreator was again used (New File or Project... under the File menu). Under File and Classes the C++ option was selected and then C++ Class was selected to create both files and Choose... was clicked.

On the next C++ Class Wizard dialog, the Class name: was set to EditBox, Base class: was set to QTextEdit and for Type information: the Inherits QWidget option was selected.  The rest were left to the filled in defaults.  On the final Project Management dialog, git was selected to add to version control and the wizard was finished.

For now, nothing was changed in the created editbox.h and editbox.cpp files except the customary comment headers were added and the formatting was corrected to match the style of the rest of the project files.  Functionality for the EditBox class will be implemented in the commits that follow.  The sources files were also added to the CMake build file, and because the EditBox class contains QOBJECT, the editbox.h file was added to the MOC sources instead of the header files variable.

A new EditBox member pointer was added to the MainWindow class.  In the MainWindow constructor, an EditBox instance was created.  There is no need to give it a parent here because the next call to setCentralWidget() does this automatically, and makes the edit box widget the main widget of the main window.  This also means that for new there is no need to delete the EditBox instance because Qt will do this when the MainWindow instance is deleted upon the program closing.

Eventually this basic mechanism of how the single EditBox instance is maintained will change since there will be a need to have multiple edit boxes open (the plan is that subroutines and functions will be contained in their own edit boxes).  The exact interface hasn't been designed or decided yet (split windows, tabs, multiple windows, etc. are all possibilities).

[commit de0ec4eb2b]

C++ Explicit Constructors

The new EditBox class was created using QtCreator's new class wizard and I noticed that it put the explicit keyword in front of the constructor definition (it also did this with the MainWindow class).  (More about the new EditBox class in the post.)  Curious what this keyword does (which was added since I learned C++ in the early 90's), I did some research.  The explicit keyword tells the compiler not to allow implicit type conversions on constructors that take a single argument.  Consider this partial example:

class MyFloat {
    float m_value;
public:
    MyFloat(int value): m_value(value) {}
    float value(void) { return m_value; }
};

float square(MyFloat myFloat) {
    return myFloat.value() * myFloat.value();
}

MyFloat something = 47;
std::cout << square(12) << std::endl;

On the last two lines, implicit conversions occur from int to MyFloat, which are perfectly acceptable  for this simple class.  However, if the implicit conversion was not desired, the explicit keyword can be added in front of the constructor to prevent it.  The compiler will now generate errors for the last two lines above.  These lines can be rewritten to work:

MyFloat something = MyFloat(47);
std::cout << square(MyFloat(12)) << std::endl;

This is a contrived example and would probably make sense to allow the implicit conversion in this class, however, this is not the case with the classes used in this project.  Therefore, the explicit keyword was added to all the constructors that take a single argument, which included the CommandLine, Parser, Tester, Token and Translator classes.

The most glaring constructor requiring explicit was the Token constructor Token(int column = -1) that would have allowed a statement like Token token = 47;, which does not make sense (a token should not be assigned an integer).

[commit 5979939788]

GUI – Settings and Window Title

All programs should save all of their settings upon exit and restore them so that when restarted the program starts up in exactly the way it was when it exited, because otherwise it is time consuming to set all the settings again.  Very few programs do however, but this approach will be used for this project.

Fortunately, Qt has the QSettings class to perform the saving and restoring mostly automatically.  The vendor (programmer) name and program name is provided to the constructor of the QSettings instance.  For saving, the setValue() method function is used with the name of the property to save and the value to save.  When the instance goes out of scope, the settings are saved.  For restoring, the settings are automatically read when the instance is created.  The properties are accessed with the value() method function.

The settings are stored to a platform specific location.  On Windows, this is to the registry.  On Linux, this is to a text file located in the .config directory on the user's home directory within a sub-directory for the vendor name under another sub-directory for the program name.  The file name is the program name with the .conf extension.

The settings are restored in the MainWindow constructor.  For saving, the closeEvent() function was implemented.  This function is called when a close event occurs (for example, the File/Exit menu item, the close icon, etc.) and can decide whether to accept or reject the request.  For now, the settings are saved and the event is accepted.

For now, only the position and the size of the main window is saved and restored.  These are obtained from the geometry of the MainWindow instance.  The program will now remember where it was and how big the last time the program was closed.  Additional settings will be added as the are implemented in the program.

[commit 54a5b24f69]

GUI – Initial Actions and Menu Items

The first thing to add to the GUI are some top level File and Help menus with menu entries under them.  Menu entries are added to each top level menu using actions.  Actions can also be added to the tool bar.  For now the File menu will contain an Exit entry and the Help menu will contain the About and About Qt entries.  A separator is added before the Help menu so that Qt knows to put this menu on the right side of the menu for those styles that support this (Windows does not do this and KDE only does this for certain application appearance styles).

Actions contain information including the name of the action (an ampersand '&' is put in front of the character that is the hot key for the entry), along with an optional shortcut key, icon, and a status tip.  No icons were added to any of the entries at this time.  A connection is made from the triggered signal of each action to the function that will perform the action.

All the actions are created in the createActions() function and the menus are created in the createMenus() function, both called from the MainWindow constructor.  The about() function was moved from the private section to the private slots section of the class definition so that the connection can be made from the about action.  The temporary show() function was removed since it is no longer needed.  The size of the header for program name in the About box was reduced to match the header size in the About Qt box.

Now the GUI will start, but doesn't do much beyond the menus (see image below).  The window still has the default name given when the MainWindow class was created and there is just a generic program icon.  There is also a blank tool bar under the menu bar.  The dot or two on the left side of the tool bar allows the bar to be dragged to any side of the window and even detached from window.  Icons (via actions) will be added to the tool bar later.

[commit 16e6755c0d]

Initial GUI Design Plan

A plan is needed for what form the GUI will take for the program initially, especially considering that only the translator and parser are implemented (and only for a limited number of BASIC commands).  The basic GUI will consist of a menu bar, tool bar, status bar and the main editing window.

This menu bar will probably only consist of the File, Edit and Help menus to start.  The File menu will start with New, Open, Save, Save As, and Quit entries.  The Edit menu will start with Copy, Cut, and Paste entries.  The Help menu will have About and About Qt entries (the about Qt is customary for Qt applications and shows information about the version of Qt used to build the program).  The initial tool bar will have buttons for items in the File and Edit menus.

Most of the effort for this initial GUI will be in the main editing window and getting it to work for the requirements needed for the interactive nature of the interactive compiler.  Namely, the code will need to catch when the enter key is hit so that the current line can be read from the editing box, compiled (translated and encoded) and stored in internal memory.  Eventually the line will need to be recreated from the internal representation back to the original text (or close to it).

Since only the translator is currently implemented, each line entered into the editing window will be translated to the RPN (reverse polish notation) list.  The tokens of the  RPN list will be converted to text (as now by the test code) and displayed in a special area in the GUI known as a dock widget.  A dock widget can be moved and docked to any side of the main editing window, and can also be undocked from the application window.  This dock widget will use to validate correct operation of the program.

Qt Transition – Release

The Qt transition is now complete and the implementation of the GUI can begin.  But first this is a good point to make a development release.  Release 0.2.0 was made (branch0.2 was merged to the master branch and tagged v0.2.0).

There is one issue when running the program on Windows when starting the program from Explorer.  A console window is opened underneath the GUI (About box), which is closed upon exit.  This can be removed by adding the WIN32 option to the add_executable command in the CMake build file.  However, this causes the command line options to no longer work.  This issue will be resolved later.

Archive files containing the source files and binary files (with test files) have been uploaded to SourceForge.  For Windows, there is also the ibcp‑libs.zip file that contains all the dynamic linked libraries required to run the program if the MinGW and QtSDK packages have not been installed (extract in the ibcp directory).  Linux should already have the required libraries installed.

This concludes the 0.2 development series.  Implementation of the GUI elements will now begin with the 0.3 development series.

[commit 85d28cd9e5]

GUI Preparation – About Box

Qt contains a static library function for displaying an about box, QMessageBox::about().  All that is needed is the title for the dialog and a string with the contents for the dialog window.  This string supports a limited set of HTML tags for formatting the text.  There is an OK button to close the dialog.  The creation of the about string and call to the Qt about function was put into the about() function in the MainWindow class.

The about string contains the full name of the program using the HTML header tag for emphasis.  As done in the Tester run function, the lines of GPL statement are added next.  Instead of putting the program name as the first part of the copyright line, the version string will be used instead with the string "Version" in front of it.  For the about box, the tr() function is used to translate the strings.  Since this is a preliminary about box, a placeholder for the full GUI, an italicized message stating such is added next.  This is followed by the command line usage string (modified to show all the options are optional).  An image of the about box running on Windows 7 is shown below.

So that the new about function has access to the GPL statement, version string, copyright year and usage string, the CommandLine instance was made a member variable as a pointer to the MainWindow class instead of being temporary in the constructor.  The instance is created in the constructor and deleted in the destructor.

The show() function for the QMainWindow class was temporarily reimplemented in the MainWindow class to prevent the full GUI from appearing (which is currently empty).  The reimplemented function calls the about() function and then does a single shot timer connected to the application quit function to end the program once the event process loop is entered.  Finally, a check for no command line options was added towards the beginning of the constructor to exit the constructor (which will start the GUI in the main function).

[commit 6eab34398c]

GUI Preparation – Usage String

Since for now the GUI is only going to pop up the About box and then exit, it would be nice if it included some information about how to use the program from the command line, specifically displaying the usage string that was previously output when no arguments were given (which will start the GUI).  The CommandLine class was modified to generate the usage string at the beginning of the constructor and save it in a new member variable, with a new function to access it.

Previously, the test options were obtained from the Tester instance, but this isn't created until later in the constructor and won't be created if there are no command line options (the constructor will return).  The Tester options access function didn't actually use any instance variables, so this function was made a static member function so that now an instance isn't necessary to access the test options.

[commit 3b93360cff]

GUI Preparation – Version String

One of the items needed in the About box is the version string.  Two minor changes were made to the CommandLine class so that it can provide the version string.  The previous version() function was renamed to isVersionOption() to mirror the name of the isHelpOption() function.

A new version() function was added to access the version string.  The version string is accessed from the ibcp_RELEASE_STRING definition contained in the CMake generated ibcp_config.h header file (from ibcp_config.h.in).  CMake gets the release string from either git (if the repository is present) or from variables set in the CMakeLists.txt file.  The actual version string starts at the seventh character of release string, which skips over the "release" part of the string.

An include statement could be added to whichever source file needs the release string, but keeping the include in a single source file and providing access functions to its values allows this to be updated in the future without having to change a bunch of other source files.  This also applies to the copyright year value.  The CommandLine class also provides access to the program name.

[commit 5431b8f9b4]

GUI Preparation – GPL Statement

The lines of the GPL statement was implemented as a QStringList in the CommandLine class.  The intention was to use this string untranslated for the test output (so the output matches the expected output files).  The QT_TR_NOOP() macro was used on the strings, so that the strings could be found by the Qt translation utilities.  The tr() function would be used later (by the GUI's About box), to translate strings (given the program was set up to do translations and the appropriate translation file was available).

However, this is not how the tr() function works.  The tr() function takes a constant char pointer and translates the string.  It does not accept a QString, so the scheme described above will not work.  Therefore, the GPL statement was changed from a QStringList to a const char * array, and also changed from a regular member to a static member.  The initialization of which was moved outside of the CommandLine constructor.  The variable was also appropriately prefixed with a 's_' to represent a static member.

The first line of the GPL statement requires special handling:

"%1  Copyright (c) 2010-%2  Thunder422"

Where the %1 and %2 are place holders for the program name and the current copyright year.  These were previously filled in by the CommandLine constructor when the QStringList was created.  This can only be done after the string is in a QString, in other words, after it has been translated (if it is going to be translated).

The Tester run function previously received the GPL statement (as a QStringList argument), which it simply output.  However, since the statement is now raw character strings, it will need to fill in the first line with the program name and copyright, neither of which it had access to.  These could have been added as additional arguments, but instead, the argument was changed to a CommandLine instance pointer, which has new access functions for these values.  After converting the GPL line to a QString, if at the first line, the program name and copyright year are filled in.

One other minor problem in the Tester run function was discovered and corrected with the interactive testing mode.  The "Testing Xxx..." string was being output before the GPL statement and it should have been after the statement and the "Table initialization successful" message.

[commit c25848a1829] [commit e27358a938]

GUI Preparation

The 0.2 development series is going to conclude with the program displaying its about box and then exiting.  The GUI elements will be added in the 0.3 development series.  Before adding the about box, some modifications to existing classes are needed, which will occur over the next set of commits.  But first, this is probably a good time to create the v0.2-6 tag as there have been 11 commits since the last development tag.

The base GUI is already present in the program, which was added by default when the main window class was created by new class wizard in QtCreator.  This GUI only contains a blank menu bar, tool bar and status bar.  If it was activated, the only thing present beside the window title (with the normal minimize, maximum, close, etc. icons) would a blank window with an empty tool bar that can be docked (more on this later) on any of the four sides of the window.

However, the program is not currently activating this window because it exits with a usage message if no options were present on the command line.  The command line and tester classes need some minor modifications before the about box can be implemented, which will contain information that will be obtained from the command line class (version, GPL statement, etc.).

[commit 6f55c2ffae]

Table Initialization – Revisited

The Table class was modified to be singleton class (see November 14).  This implementation was modified.  To be consistent with the Token class, which is initialized with a static initialize() function, the Table class create() function was renamed to initialize() and changed to return nothing instead of a list of errors.

The old initialize() function, a normal private member function, was renamed to setupAndCheck() and still returns a list of errors.  Two new static functions were added to access the error list: hasErrors() to report if there were any errors detected and errorList() to return the list of errors.  Both fatally abort the program if the initialize function was not called.  The initialize function stores the error list returned by setupAndCheck() into a new static error list member variable.

The two static members, one for the pointer to the single instance and the other for the error list are now prefixed with 's_' instead of 'm_' to denote a static member as opposed to a regular member variable.  The static member variables to the Token class were also renamed with the 's_' prefix.

The new initialize function also checks if either the instance pointer is not null or if the error list is not empty to determine if the table instance was previously created or at least attempted.  When an error is found, the instance is deleted, so the instance pointer alone can't be used to determine if the instance creation was attempted.  Similarly, the new error list access functions also check if both the instance pointer is null and error list is empty to determine if there was a creation attempt.  The check for a non-empty error list was also added to the instance() access function.

The Token and Table initialize function calls were moved from the Tester run function to the main function.  This keeps the initialization in a single location.  The Tester run function still contains the check for table errors.  The error check was not moved to main because when the GUI is started, any table errors need to be reported in an error dialog box, not to the console output.  When the program is started from say an OS start menu or file browser, there is no console for these errors and the program will inexplicably fail to start.  Now work on the GUI can begin...

[commit 5c5da1f069]  [commit e0474f5144]

Standard Error Output - Oops

My job took me away from this project the past week.  In making the next set of changes, I discovered that the last commit did not compile.  During the development of the standard error output changes, the coutClose() function (which closes the current channel if open) was originally named cclose().  At the last moment, this was renamed to the more appropriate coutClose(), but in the haste to get the code committed, the code was not compiled and retested.

It has been recent policy recently make sure every commit pushed to the repository compile and test successfully, at least on the development platform (Linux).  Any problems with testing would be noted in the commit message.  The last commit failed this policy and I apologize (and worst, it went for a week in this state).

When a development tag is added, it is validated to compile and test successfully on both the Linux and Windows platform (specifically XP, though it should work on 7 also).  Again any problems are noted in the commit message.  For an actual release however, it will also be tested on the Windows 7 platform (and there should be no test issues).

[commit 4ffed94ea2]

Standard Error Output

Command line error messages should be sent to the standard error channel; the Qt qWarning() function should not be used because these messages can be disabled.  The cout() function was modified to accept a FILE stream (channel) pointer, either stdout or stderr, with stdout the default.  The qWarning() calls were changed to cout(stderr), which made these lines cleaner because the qPrintable() function is not longer needed to output QString values.

There was also a qWarning() call in the Tester run function when table errors are detected.  These only occur when there are problems in the table entries and are followed by a qFatal() call (which terminates the program).  This qWarning() call was changed to a qCritical() call, whose messages can not be disabled.

Previously, to get the usage message, invalid arguments had to be specified.  To get the usage message without returning an error, new help options were added (either '-?' or '-h').  The usage message will be output to standard output channel when using these options, but to the standard error channel for invalid arguments.

When an error occurs in the Tester run function, like when the test file can't be opened, the standard output channel needs to be closed and the standard error channel opened to output the error message.  The new function coutClose() was added to the CommandLine class, which closes the current channel (if open), which is called before outputting the error message from the Tester instance.  The code for this function was pulled from the destructor, which was replaced with a call to the new function.

[commit e64eadee4a]

Returning Command Line Errors

When the starting of the single shot time to force the application to quit upon entering the event loop was replaced by a simple return (of 0), I realized that it should really be returning an error code if there is an error in the command line options.

To accomplish this, the processed flag in the CommandLine class was replaced with return code variable, which has three values: 0 for successfully processed command line only option, 1 for error occurred with the command line options, and -1 for no command line only options (in other words, start the GUI).  An access function was added for the return code.

The processed access function remains (so callers don't need to be modified), but now returns true if the return code variable is not negative.  A return code variable was also added to the MainWindow class along with an access function.  In the constructor, the return code is obtained from the command line instance when the GUI active flag is set to false (when the command line was processed).  The main function was modified to return this code.

By convention, a command returns a code of 0 to indicate success and any other value to indicate an error.  Some commands return a specific error code value, but here just a general error occurred code (1) is returned.  To test if this new functionality was working correctly, this command was used:

ibcp -v && echo no error

This command will output the version number followed by the "no error" message.  If the -v is replaced with an invalid option, the "no error" message will not be output.

[commit 164fb19fe8]