Form properties & events

Form properties#

Select the Form itself in the Designer to edit window settings. Defaults below come from the application contract; a template may save different initial values. Use the access label before assigning a property in BASIC.

Try window properties without losing the close action#

In a copy of the first-app project, select frmMain. Set Caption to Greeting practice, Width to 640, Height to 360, MinWidth to 480, MinHeight to 260, BorderStyle to Sizable and StartUpPosition to CenterScreen. Keep ControlBox, MinButton and MaxButton enabled. Check and Run, resize the window, then stop it. The following complete Form event can be added for a runtime assignment exercise:

Private Sub Form_Load()
    Me.Caption = "Greeting practice"
    Me.Opacity = 1
    Me.Tag = "practice-window"
End Sub

Keep the existing Click handlers unchanged. Confirm the title, resize limits and close action. Do not assign StartUpPosition in this handler. If experimenting with BorderStyle = None or ControlBox = False, first provide a tested button handler containing Unload Me; those settings change how the user can close the window.

Form events#

The signatures below are contracts, not complete implementations. Add the body for your task and the matching End Sub. Preserve each parameter’s type and ByRef direction.

Initialize#

Occurs once after controls and event bindings are created, before the Form is loaded.

Private Sub Form_Initialize()

No parameters.

Load#

Occurs once after initialization and before the Form is first shown.

Private Sub Form_Load()

No parameters.

Shown#

Occurs after the Form becomes visible; this lifecycle event may use Async Sub.

Private Sub Form_Shown()

No parameters.

Activate#

Occurs when this Form becomes the active ordinary window or active child of its MDI container.

Private Sub Form_Activate()

No parameters.

Deactivate#

Occurs when this Form ceases to be the active ordinary window or active child of its MDI container.

Private Sub Form_Deactivate()

No parameters.

Closing#

Occurs before a close attempt; set Cancel to True to keep the Form open and suppress Closed.

Private Sub Form_Closing(ByRef Cancel As Boolean)

Closed#

Occurs once after an accepted close, before the Form resources become unavailable.

Private Sub Form_Closed()

No parameters.

Resize#

Occurs after the effective Form client size changes.

Private Sub Form_Resize()

No parameters.

MouseDown#

Occurs when a pointing-device button is pressed on the Form surface outside authored child controls.

Private Sub Form_MouseDown(ByVal Button As MouseButton, ByVal Shift As KeyModifiers, ByVal X As Double, ByVal Y As Double)

MouseUp#

Occurs when a pointing-device button is released on the Form surface outside authored child controls.

Private Sub Form_MouseUp(ByVal Button As MouseButton, ByVal Shift As KeyModifiers, ByVal X As Double, ByVal Y As Double)

MouseMove#

Occurs when the pointer moves over the logical McBasic™ control; Button contains the currently held buttons and X/Y are local DIP coordinates.

Private Sub Form_MouseMove(ByVal Button As MouseButtons, ByVal Shift As KeyModifiers, ByVal X As Double, ByVal Y As Double)

MouseWheel#

Occurs for normalized pointer-wheel input; Delta is portable, and X/Y are local DIP coordinates.

Private Sub Form_MouseWheel(ByVal Delta As Double, ByVal Shift As KeyModifiers, ByVal X As Double, ByVal Y As Double)

DragOver#

Occurs while a control dragged inside the app (DragMode or the Drag method) moves over the Form surface outside other controls: State is 0 when it enters, 2 while it moves over and 1 when it leaves; Source is the dragged control and X, Y are Form client DIP coordinates.

Private Sub Form_DragOver(ByVal Source As Control, ByVal X As Single, ByVal Y As Single, ByVal State As Integer)

DragDrop#

Occurs when a control dragged inside the app (DragMode or the Drag method) is released over the Form surface outside other controls; Source is the dragged control and X, Y are Form client DIP coordinates.

Private Sub Form_DragDrop(ByVal Source As Control, ByVal X As Single, ByVal Y As Single)

KeyDown#

Occurs before the focused control receives a physical key when KeyPreview is True; set Handled to suppress control delivery.

Private Sub Form_KeyDown(ByVal KeyCode As KeyCode, ByVal Shift As KeyModifiers, ByRef Handled As Boolean)

KeyPress#

Occurs for committed Unicode text before the focused control receives it when KeyPreview is True; set Handled to suppress control delivery.

Private Sub Form_KeyPress(ByVal Character As String, ByRef Handled As Boolean)

KeyUp#

Occurs before the focused control receives a physical key release when KeyPreview is True; set Handled to suppress control delivery.

Private Sub Form_KeyUp(ByVal KeyCode As KeyCode, ByVal Shift As KeyModifiers, ByRef Handled As Boolean)

QueryUnload#

Occurs before closing; set Cancel to a nonzero value to keep the Form open.

Private Sub Form_QueryUnload(ByRef Cancel As Integer, ByVal UnloadMode As Integer)

Unload#

Occurs once after closing is accepted and before Form resources are released.

Private Sub Form_Unload()

No parameters.