Compiled Application from Standard EXE Project

This final objective asks you create an executable file from a completed Visual Basic application.  Two options are available: Under the Compile tab of the Project Properties dialog box, you can select Compile to P-Code or Compile to Native Code (see Figure 2.10).  Compiling to native code is the default.

Figure 2.10The Compile tab of the Project Properties dialog box enables you to control the way in which you compile your completed application.

Interpreted P-Code

By selecting P-Code, the modules of your Visual Basic application are compiled into what is called pseudocode or false code.  An interpreter program that then produces machine language instructions reads the coded instructions.  All versions of Visual Basic prior to Visual Basic 5.0 were interpreted from P-Code.

Interpreted programs offer some advantage.  Applications can be designed rapidly because new code can be tested immediately, without time-consuming compilation.  They also offer some security advantages in networked applications.  You can rely on the interpreter to serve as a buffer between an application and computer hardware.  This is the security model built into the Java programming language, for example.  To their disadvantage, interpreted programs tend to run slower than compiled programs.

Compiled Native Code

With Visual Basic 5.0, you can create native code compiled applications:  The compiler takes the modules of your project and creates a machine language compiled application.  Although the native code executable does not require interpretation, it still depends on other files to run.  These files consist, mainly, of the object linking and embedding (OLE) libraries that make up the ActiveX architecture upon which Visual Basic is based.

One way to think about the difference between interpreted and compiled programs is to compare it to translating a letter from English to German (or another language).  A compiled program translates the entire letter once, producing machine-language instructions.  An interpreted program translates each letter every time the letter is read, producing P-Code, which is then translated into machine language.

The Make Tab of the Project Properties Dialog Box

When you decide to create an executable, the Make tab of the Project Properties dialog box comes into play.  The Make tab presents general attribute options for your executable (see Figure 2.11), including the title of the application, the icon used to represent the application when it is minimized, and different version options. The Make tab also enables you to set command-line arguments for your application should you decide to use them.

Figure 2.11The Make tab enables you to set version numbers, version information, application attributes, command-line arguments, and conditional compilation arguments.

Exercise 2.9  Creating an Executable Application

This exercise asks you to create a make file from the Happy Birthday application created in Exercise 2.8.

1. Open Exercise 2.8 if it is not on the screen.
2. Choose File, Make Project2-8, if this reflects the name you gave your project.
3. When the Make Project dialog box opens, select a file name, such as BDAY1.EXE, and click OK.  That's it. You have created a native code executable file. Remember that native code is the default.
4. Choose File, Make Project2-8 again, and when the dialog box opens, click Options.
5. Click the Compile tab.
6. Click Compile to P-Code, and click OK to return to the Make Project box.
7. Select a different file name, such as DAY2.EXE.
8. Close Visual Basic, and start Windows Explorer.  Locate both DBAY1.EXE and BDAY2.EXE.  Click BDAY1.EXE to run the program.  Close BDAY1.
9. Click BDAY2.EXE to run the program.  Close BDAY2.

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Writing Visual Basic Instructions-2

Exercise 2.6  Changing the Font Size Property

In this and the next two exercises, you change the properties of the form used in Exercise 2.5.

1. Choose File, Open Project, if necessary, and select View, Project Explorer, or click the Project Explorer icon to open the Project window.  Click View Form.
2. Click the form to give it the focus, and press F4 to open the Properties dialog box.
3. Click font and change the font size to 18 points (or to another size if the size is not available on your system).
4. Run the program.  Click to display the first sentence.  Press a key to display the second sentence.
5. Exit to continue with the next exercise.

Exercise 2.7  Changing the Font Style Properties

In this exercise, use the form from Exercise 2.5 once again.

1. Open the Properties dialog box and open the Font dialog box by double clicking the Font property.  Change the Font to Bookman Old Style (or another font if your system does not have this font installed).
2. Change the style to bold and italic.
3. Run the revised program.  Click to display the first sentence (it should be in bold and italic).  Press a key to display the second sentence.
4. Exit and save your project at this time.  The next exercise asks you to begin a new project.

Exercise 2.8  Adding a Message to a Form and Changing Property Settings

In this exercise, you write a new procedure and change properties.

1. Open a new project.
2. Add the following Form_Click() Visual Basic procedure to the form:

   Private Sub Form_Click()
   'This procedure will display a Happy Birthday message
   Print "                 HAPPY"
   Print "                 BIRTHDAY"
   End Sub
   

3. Change the following form properties:

   Property	Setting
   Backcolor Palette	= &H00FF00FF& (light purple)
   BorderStyle	= 1 'Fixed Single
   Caption	= Today is the day
   Font Style	= Italic
   Font	= Arial
   Font Size	= 24
   ForeColor Palette	= &H00FF0000& (blue)
   WindowState	= 2 'Maximized

4. Run your program.
5. Exit and save your program. Give the form a unique name, such as BDAY.FRM. Give the project a similar name, such as BDAY.VBP.

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Writing Visual Basic Instructions

The final type of window discussed here is the Code window.  To open the Code window for a form, click the Project Explorer and click View Code, or choose View, Code.  This opens the window shown in Figure 2.7.  The object shown is the Form; the procedure is shown as Load().  The title bar reads Form1 because you have not changed the name of the form.

Figure 2.7 This Code window shows the start of a Form_Load() procedure.

The Code window contains the first two coded instructions, which are entered for you.  The first combines the name of the object with the name of the event procedure.  This coded instruction is shown in the following example, in which Load() is a special type of event:

Private Sub Form_Load()

It occurs when a form is first loaded.  However, suppose you want to change the event from Load() to Click().  By selecting Click (click the procedure list box and scroll to Click, as shown in Figure 2.8), the first coded instruction changes to the following, in which Click() is another type of event:

Private Sub Form_click()

It is triggered by a mouse click.

Figure 2.8 The Code window now shows the start of a Form_click() procedure.

The event has now been changed from occurring at the time the form is loaded to the time when the form is clicked, with the user controlling the time of the event with the click of the mouse.

The ending instruction stays the same.  It reads as follows, which means the end of the procedure (sub):

End Sub

Exercise 2.4  Adding a Click() Procedure

In this exercise, you begin a new project.

1. Choose File, New Project and open a Standard EXE project.  If the last project is still on-screen and has not been saved, you will be asked if you want to save changes to P2-3.vbp? Click No, unless you have already saved it.  Either way will not lead to problems.
2. When Form1 appears, double-click to open the Code window.
3. Change the Project name to Project2_4.
4. Change the procedure name from Form() to Click() in the procedure list box.

   Your code should read as follows:

   Private Sub Form_Click()
   End Sub
   

5. Type the following to create the procedure:

   Private Sub Form_Click()
   'This procedure will display a message on the form
   Print
   Print
   Print "When you click, look at what happens!"
   End Sub

6. Close the Code window by double-clicking the Control box icon.
7. Choose Run,Start;click the Start icon on the toolbar; or press F5 to run your procedure. When Form1 appears, place the mouse pointer on the form and click. What happens?
8. Click the form again. What happens? It makes you want to click forever doesn't it?
9. Choose Run, End from the menu bar or press the End button on the toolbar to return to the design of Form1.
10. Save this form and project. You can call the Form F2-4.frm and the project P2-4.vbp if you want to use them in later exercises; however this is not necessary. Continue with the next exercise using the same form.

Exercise 2.5 Adding a KeyPress() Procedure

In this exercise you add a second procedure to a form. Figure 2.9 shows the revised form. This exercise assumes you have completed Exercise 2.4 and are using that form.

Figure 2.9

Adding a KeyPress() procedure to the form places more than one procedure on the same form.

1. Choose View, Code from the menu bar. The code you wrote for Exercise 2.4 should appear.
2. Choose KeyPress from the Procedure list box, and observe what happens to your code.
3. type the following to complete this procedure:

   Private Sub Form_KeyPress (KeyAscii as Integer)
   'This procedure will display a different message on the screen
   Print
   Print
   Print "    When you press a key, look at what happens!"
   End Sub

4. Close this procedure (using the Control menu icon) and run the revised program. There are four ways to run your program:
   • Choose Run, Start.
   • Choose Run, Start with Full Compile.
   • Press F5.
   • Press the Start button on the toolbar.

   This time, press F5 to start your program; then as a test, do the following:

   1. Click the form.
   2. Press a key.
   3. Press a second key.
5. Click the End button on the toolbar to stop your program a different way, or choose Run, End to stop the program.
6. When you are returned to Form1, double-click the form to open the Code window. What code appears?
7. Scroll through the list of procedures in the Procedure menu. Coded procedures are displayed in bold.
8. Save this form and project at this time. You will be asked to work with the form and project in the next several exercises, but it is wise to save your work periodically. You can save your form as F2-5.frm and your project as P2-5.vbp to keep your examples in sequence. Name the project Project2_5 before saving.

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Disabling the Minimize Button

With the first two border styles, the Minimize button appears unless it is disabled by the Minbutton property to change the setting to False.  (With this property, there are only two choices: True and False.)

Disabling the Maximize Button

With the first two borderstyles, the Maximize button appears, unless it is disabled.  To disable the button, double-click the MaxButton property to change the setting to False. (Like MinButton, only two choices are available with MaxButton: True and False.)

Disabling the Control Box

With the first three border styles, the control box appears unless it is disabled.  To disable the box, double-click the ControlBox property to change the setting to False. (The two settings for ControlBox are True and False.)

Changing the Window State

The WindowState property determines the appearance of the form at runtime.  Table 2.3 shows its three settings.

Table 2.3 The Settings for the WindowState Property

Value	Setting	Description
0	Normal	The form appears in normal size (the default).
1	Minimized	The form is minimized and appears as an icon (either on the taskbar or above it) when the application is run.
2	Maximized	The form is maximized and expands to fit the entire screen when the application is run.

Changing the background Color

Part of the enjoyment of working with Visual Basic is the ease with which colors can be added to a form.  Color settings are expressed in hexadecimal notation (base 16). The designers of Visual Basic did not expect you to work with hexadecimal numbers and instead provided a color palette.  To open the palette, double-click the Backcolor setting and click Palette.  When the Color palette appears, click a color to change the background color of the form.  Following the click, the hexadecimal number assigned to the color appears in the text box.

Changing Font Properties

When working with text, Visual Basic enables you to change the font (or text style) you are working with.  To determine which fonts are available on your system, open the Properties window, highlight Font, and click the ellipsis button to the right.  A dialog box appears for setting numerous font properties, including Name, Bold, Italic, Size, StrikeThrough, and Underline.

Changing the Foreground Color

The ForeColor property determines the color of the text and graphics to be displayed.  This differs from Backcolor, which determines the background color of the object.  To set this property, double-click ForeColor and click Palette.  Make the color selection using the palette.

Changing the Startup Position

The StartUpPosition property specifies the position of the form when it first appears.  Table 2.4 shows its four settings.

Table 2.4 The Settings of the StartUpPosition Property

Constant	Value	Description
vbStartUpManual	0	No initial setting specified
vbStartUpOwner	1	Center on the item to which the UserForm belongs.
vbStartUpScreen	2	Center on the whole screen.
vbStartUpWindows	3	Position in upper-left corner of screen.

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Opening the Properties Window and Changing Form Properties

Besides a Project Explorer window, each form (or control) contains a Properties window.  As stated in Running a Visual Basic Program, a property is a named attribute of an object.  Properties are used to change the appearance or behavior of objects.

Figure 2.6 illustrates the default Properties dialog box for a form.  If this box is not visible, you can bring it into view by pressing the F4 function key, or choosing View, Properties Window.  With the form having the focus, press your right mouse button and drag down the Properties list.

Figure 2.6
The Properties dialog box of a form contains the built-in form attributes that you can change.

Over 50 properties can be set for a form.  Although this number seems overwhelming at first, some properties are used so frequently that they represent an initial set to remember.

Form Properties

Caption Name BorderStyle MinButton MaxButton ControlBox WindowSize BackColor

FontName FontSize FontBold FontItalic FontStrikethru FontUnderline ForeColor StartUpPosition

To simplify this list somewhat, the items can be grouped by their uses:

• Seven properties deal with the way in which the form or text appears on the display screen (Caption, BorderStyle, MinButton, MaxButton, ControlBox, WindowSize and StartUpPosition).
• The identification of an object is specified by the Name property.
• Font settings are controlled using the Fonts dialog box (FontName, FontSize, FontBold, FontItalic and FontStrikethru).
• Color settings (ForeColor and BackColor) use a special palette.

There are three ways to change most property settings:

• Click the property to highlight it, and enter (type in text) the new property setting in the text box.
• Double-click the setting to view the alternative settings.
• Click the down arrow to open the drop-down menu for property settings.

Properties for fonts and color launch a separate dialog box for you to enter settings.

Changing a Caption

The Caption property enables you to change the title that appears on the top of a form.  Instead of Form1, use the Caption property to add a title.  To change the caption, select Caption in the Properties dialog box and type the new title in the text box next to the property name.

Changing a Form Name

The Name property specifies the name of the form to be used in writing Visual Basic code. Remember the following rule: The name, not the caption, is the identifier.  When writing coded instructions, the Name property appears as the object name.  To change the name, select Name in the Properties dialog box and type the new name.

Changing the Border Style

The BorderStyle property enables you to change the appearance of the form’s border.  To change the border setting, double-click the current setting to reveal other choices, or click the down arrow to open the drop-down list of the six options.

If you are uncertain about the six border choices and their precise effects, click BorderStyle to give it the focus in the Properties dialog box, and press F1 (the Help function key).  Visual Basic Help displays the six style choices and explains their effects, as shown in Table 2.2.

Table 2.2 The Settings for the BorderStyle Property

Setting	Style	Description
0	None	No border or border-related elements.
1	Fixed Single	Can include Control menu icon, title bar, Maximize button, and Minimize button.  Resizable only using Maximize and Minimize buttons.
2	Sizable	The default.  The size can be changed using any of the optional border elements listed for setting 1.
3	Fixed Dialog	Can include Control menu icon and title bar; can’t include Maxiimize or Minimize buttons.  Not resizable.
4	FixedToolWindow	Under 16-bit versions of Windows and Windows NT 3.51 and earlier, behaves like Fixed Single.  Does not display Maximize or Minimize buttons.  Not resizable.  Under Windows 95, displays the Close button and displays the title bar text in a reduced font size.  The form does not appear in the Windows 95 taskbar.
5	SizableToolWindow	Under 16-bit version of Windows and Windows NT 3.5 and earlier, behaves like sizable.  Docs not display Maximize or Minimize buttons, Resizable.  Under Windows 95, displays the Close button and displays the title bar text in a reduced font size.  The form does not appear in the Windows 95 taskbar.

The online Help is one of Visual Basic’s strongest features.  Remember, the F1 key is your friend!  Use it often.  The language is just too vast to remember all of it.

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The concept of Focus

The concept of focus is important in Visual Basic.  The object that is selected (such as a form, control, or menu bar selection) is said to have focus.  In order for Visual Basic to know what file to save, it is necessary to click the object to give it focus, making it the active object.  Likewise, to remove a file, the object must be given focus.  To remove a file, open the Project window, click the file to remove, and choose File, Remove and the name of the file to remove will also appear.  An alternative is to display the Project Explorer, click the file that you want to delete, and right-click to produce the shortcut menu shown in Figure 2.3.  We discuss the concept of focus at length later.  There are even unique events, such as Gotfocus and LostFocus, that deal with this issue.

Figure 2.3 Display the Project Explorer and right-click to reveal several file optiions, including a command for removing a file from a project.

Exercise 2.2  Using the Remove and Add Commands

This exercise assumes that you completed Exercise 2.1 and saved the form as F2-1.frm.

1. Open a new Standard EXE project, and change the name of the project to Project2_2 (click Project, Project1 Properties).
2. Choose Project, Remove Form1.Form1 must have the focus because it is the only object assigned to the project.
3. Choose Project, Add File.  Navigate through Windows to the location where you saved F2-1.frm, and add this form to your Project (see Figure 2.4).
   

   Figure 2.4

   The Add File dialog box lists saved forms that can be added to a project.

4. Open the Project Explorer Window, and give form F2-1.frm the focus.
5. Choose File, Save File As (or click the right mouse button).  When the dialog box opens, navigate to the location where you want to save the file, and name it F2-2.frm.
6. Open the Project Window again and observe what happens.  The name of the form has been changed and assigned to the new project.
7. Choose File, Save Project As.  In this instance, you are not asked to name the form because it has already been named and saved.  Instead, you are asked only to name the project, which we named P2-2.vbp.

Other File Menu Commands

Besides the four Project menu commands and the two file commands found on the File menu, the latter also contains the Print and Print Setup commands and the Make Project1.Exe commands, as follows:

• Print – Choose File, Print to display several options for printing information about a project (see Figure 2.5).  You can print the form image, code, or the form as text, and you can choose to print information for a module or for the entire project.
• Print Setup – Choose File, Print Setup to launch the standard Windows Print Setup dialog box.
• Make Project1.Exe – Choose File, Make Project.Exe to create an executable application.  Project modules are compiled into a single .EXE file.  This file is either a P-Code interpreted executable or a native code executable file.  (The two code formats are explained in “Interpreted P-Code,” and “Compiled Native Code,” later.)

Both types of executables require runtime files.  The Visual Basic Setup Wizard can help you determine which runtime file your application requires.

Figure 2.5 The Print-Project dialog box enables you to choose the parts of an application that you want to print.

Exercise 2.3  Using the Print Command

This exercise is designed to show you the type of information printed for a project.

1. Open a new Standard EXE project.
2. Choose File, Print.
3. When the dialog box appears, click Current Project, Form Image, Code and Form as Text.
4. Click OK.

What is the difference between the Form Image and the Form as Text choice!  Why is there no computer code?

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Naming a Project

Each time you begin a new project, the default name, Project1, appears at top of the form.  Unless you change the name, every project you work on will be named Project1.  To change the name, choose Project, Project1 Properties (see Figure 2.2), and type a new project name.  For example, you might enter Project2_1 for this initial project.

Figure 2.2 The Project Properties dialog box is used to change the name of the project from the default, Project1, to a name of your choosing.

Exercise 2.1 Using the Save Project As Command

This exercise asks you to do very little, but it does introduce you to the file naming conventions. Start Visual Basic, and perform the following steps:

1. Open a Standard EXE new project.
2. Choose Project, Project1 Properties and change the name of the project to Project2_1. Click OK. This new name should appear on the topmost title bar of Visual Basic.
3. Choose File, Save Project As. A dialog box appears and asks if you want to save the file as Form1.frm. If you click Cancel, the form is not saved and you have to rebuild it if you need it. Imagine that you spent an hour perfecting a form. Unless you save it, your work will be lost.
4. Before you click Save, navigate to the location where you want to save the file, and assign a name to the form. Assign a unique name - something other than the default, Form1.frm. You can use the notation F2-1.frm to indicate that this form goes with exercise 2.1 (not very clever, but it works). A more descriptive name would be better.

   If you want to store the form on a diskette placed in the a: drive of the computer, navigate to the drive and type F2-1.frm.

5. After the form has been saved, a second dialog box appears asking you to assign a name to the project. Again, assign a unique name (not the default, Project1.VBP). You can call it P2-1.VBP to indicate that this project goes with Exercise 2.1. Here too, a descriptive project name would be better.

If you want to save the project on a diskette placed in the a: drive of the computer, navigate to the drive and type P2-1.VBP

The Add File and Remove File Commands

Files can be added to, or removed from, the .VBP project file using the file commands contained on the Project menu. When adding or removing files, keep in mind that you are adding or removing files from a project. The following are two Project menu commands that you will use often in this book:

• Add File - Choose Project, Add File to open a dialog box (see Figure 2.4) that enables you to navigate the Windows file directory to identify a previously saved file and to add the file to a project, for example, an .FRM (form), .BAS (coded module), .CLS (class modules), or .RES (resource file). This command is especially important when you use a file built for a different project. Simply identify the file name, and click OK.
• Remove <Name of File> - Choose Project, Remove <Name of File> to remove the file from the current Project that is active (has the focus, a term that is described next).

Other Project menu file commands include Add Form, Add MDI Form, Add Module, and Add Class Module. These enable you to add new types of forms and modules to a project.

The Save File and Save File As Commands

The following are two File menu commands that are used to save a particular file rather than an entire project:

• Save File - Choose File, Save File to save the form or module that is active (has the focus). If the file has previously been saved, this command updates the file. If the file is new, this command prompts you for the name of the file and, once entered, adds the file to a project when the project file (.VBP file) is next saved.
• Save File As - Choose File, Save File As to save the current file to a disk. This option always prompts you for the file name. Like the File, Save Project As command, File, Save File As is used to save a file for the first time or to save a copy of an existing file.

You will find file commands most useful when you want to use the same forms and modules in different projects.  There is nothing to prohibit you from using the same form in dozens of projects because each form is saved as a separate file.

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