Contains definitions and descriptions for constructing the Forms which are the basis of the Lazarus Graphical User Interface
Represents the Position and Size on Screen of an Form

poDesigned - The Form appears exactly as it is positioned and sized in the Form Designer

poDefault - The window manager decides how the form is to appear, in a default position and size

poDefaultPosOnly - keeps the Designed size, but position determined by windowmanager

poDefaultSizeOnly - keeps the Designed position, but size determined by windowmanager

poScreenCenter - Centers the form on screen

poDeskTopCenter - Centers the form on desktop

poMainFormCenter - Centers the Form on the Main Form

poOwnerFormCenter - Centers the Form on Owner form

Represents the actual State of the window on the screen

wsNormal - The window appears normal

wsMinimized - The window appears minimized

wsMaximized - The window appears maximized

TCustomForm.OnClose
TScrollingWinControl
- a class of Window Control that has one or more scroll bars
Scrolling Window Control: A window control with scroll bars. An ancestor class for many forms with scrolling windows
TCustomHintAction
- Base class for THintAction, the action for displaying a Hint
Exception in Scroll Bar
Exception class for Scroll Bar
TControlScrollBar
- base class for defining scroll bars on Forms and windows
Control Scroll Bar: Scroll Bar control for adding to windows. Can be horizontal or vertical.

This is an ancestor class for many form types and classes of windowed controls
FControl
- local variable to hold the Window Control to which the scroll bar belongs
ControlAutoScroll
- returns True if the control can Auto-Scroll
ControlHandle
- the operating system handle for this control
GetIncrement
- returns the size of the increment for each slick in the scroll bar
GetPage
- returns the size of the Page-Down (or -Up) Increment for the scroll bar
GetPosition
returns the position of the slider in the scroll bar
GetRange
- returns the valid range of values for the scroll bar movement
GetSize
- returns the size of the scroll bar
GetSmooth
- returns True if smooth scrolling is to be used
GetVisible
- returns True if the scroll bar is visible
HandleAllocated
- returns True if a handle has been allocated
SmoothIsStored
- returns True if the Smooth status has been stored
VisibleIsStored
- returns True if the Visible status has been stored
AutoCalcRange
- method for automatically calculating the range of values for the scroll bar
ControlUpdateScrollBars
- method to be used by the owner control for updating its scrollbars
ScrollHandler
- message handler to control scrolling
SetIncrement
- specifies the scrolling increment
SetPage
- specifies the page scrolling increment
SetPosition
- specifies the position of the slider in the scroll bar
SetRange
- specifies the range of values for the scroll bar
SetSize
- specifies the size of the scroll bar
SetSmooth
- specifies whether smooth scrolling is to be used
SetVisible
- specifies whether the scroll bar is to be visible
UpdateScrollBar
- method to update the scroll bar (position etc)
InvalidateScrollInfo
- method to render scroll information non-valid
TObject.Create
Create
- constructor for TControlScrollBar: performs inherited Create then initialises local flags for page, increment, position etc
The identity of the windowed control in which the scroll bar is found
Whether this is a horizontal or a vertical scrollbar
Assign
- if Source is a TControlScrollBar, copies properties to itself, else performs inherited Assign
Assigns the contents of the source object to the current object; in particular finds the increment, position, range and whether smooth scrolling is to be feature and whether the scroll bar is visible
The object that called this instance of the class
Visibility of scroll bar
Returns 'True' if scroll bar visible
Position of the indicator cursor on the scroll bar
Returns position of the scroll cursor as an integer
Finds which kind of scroll bar this is: horizontal or vertical
Reads a flag to determine which kind of scroll bar
Finds out details of the other scroll bar
Returns a link to the details of the other scroll bar
GetHorzScrollBar
- find the position and properties of the horizontal scroll bar
Returns details of the horizontal scroll bar as a pointer to a structure
GetVertScrollBar
- find the position and properties of the vertical scroll bar
Returns details of the vertical scroll bar as a pointer to a structure
Determine the size of the scroll bar
Reads or writes a flag to determine the size; by default the size is not stored
The size of the scrolling increment
The amount by which the scroll indicator moves if the triangle at either end of the bar is selected.

Read or write a flag to determine the increment, an integer with a default value of 8 (pixels)
The size of the paging increment for scrolling
The amount by which the scroll indicator moves if the cursor selects the scroll bar above, below or on either side of the scroll indicator.
Reads or writes a flag to determine paging increment; default value is 80 pixels
Determine whether smooth scrolling is to be implemented
Reads or writes a flag to determine smooth scrolling, and sets a flag is the scrolling status is stored
Position of the scroll bar
Reads or writes a flag with the position; default is zero
The range (extent) of the scroll bar
Reads or writes a flag to determine the range; default is zero
Can the scroll bar be made visible?
Reads or writes flag to determine visibility, and sets a flag if the property is stored. The Handle object (widget) is made visible if (Visible=true) and (Range>Page). To get the current visible state of the widget use the method IsScrollBarVisible.
AlignControls
- calls inherited AlignControls, then calculates sizes for the scrollbars if required
TWinControl.AlignControls
CreateWnd
- performs inherited CreateWnd then updates ScrollBars
TWinControl.CreateWnd
GetClientScrollOffset
- finds the position for scrollbars from the client, if any, otherwise sets default postiions
TControl.GetClientScrollOffset
GetLogicalClientRect
- adjusts client rect to allow for size of scrollbars
TControl.GetLogicalClientRect
DoOnResize
- performs inherited DoOnResize then updates scrollbars if needed
TControl.DoOnResize
GetControlClassDefaultSize
inserts its own defaults, overriding inherited values
TControl.GetControlClassDefaultSize
WMHScroll
- system message method for horizontal scrolling
WMVScroll
- system message method for vertical scroling
ScrollBy
- amount by which to scroll
ComputeScrollbars
- returns True if scroll bar positions need to be computed
ScrollbarHandler
- method for handling scroll bars of specified kind at specified position
Loaded
- calls inherited Loaded and updates scroll bars
TWinControl.Loaded
This constructor can override the constructor of an ancestor class
TCustomControl.Create
Create
- constructor for TScrollingWinControl: performs inherited Create then creates and intiialises the scrollbars
Can override destructor of parent class
Destroy
- destructor for TScrollingWinControl: frees the horizontal and vertical scrollbars, then performs inherited Destroy
Update the position of the scroll indicatores in the scroll bars
Checks if the scroll bars are in process of being loaded or destroyed;
if so, or if there is no valid handle, exit.
If the indicators are valid, re-computes position etc
Whether the scroll bars are visible
Does auto-scrolling apply?
Reads or writes a flag to determine auto-scrolling
The properties of the horizontal scroll bar
The properties of the vertical scroll bar
Scroll Box: A box with scroll bars
TCustomFrame
- the base type for TFrame
GetChildren
- calls inherited GetChildren then accepts ownership of all owned components that have no parent
TComponent.GetChildren TWinControl.GetChildren
Notification
calls inherited Notification then add or removes the component's action list (depending on what Operation specifies)
TComponent.Notification TControl.Notification
SetParent
- calls inherited Setparent after validity checks, then updates the action lists
TControl.SetParent
GetControlClassDefaultSize
- returns its own defaults for frame design, overriding the inherited values
TControl.GetControlClassDefaultSize
Create
- constructor for TCustomFrame: performs inherited Create then initialises styles, bounds etc
TScrollingWinControl.Create
TCustomFrameClass
- class of TCustomFrame
TFrame
- a container for all the other components on a form, or for a group of components within a form
TIDesigner
- a class describing a Form Designer
TBorderIcon
- enumerated type to specify which icon appears on the top border of the Form
biSystemMenu - The form has a System menu (Maybe not all windowmanager supports this)

biMinimize - The form has an minimize button

biMaximize - The form has a maximize button

biHelp - When you click this button a Question Cursor appears and the help routines are called if you click on an control
TBorderIcons
- set of TBorderIcon; the group of icons to appear at the top of the form
TFormStateType
- enumerated type to describe the state of a form; whether it is being created or destroyed, its visibility, whether Modal etc

The valid states are:

    fsCreating,  // initializing (form streaming)
        fsVisible,   // form should be shown
        fsShowing,
        fsModal,     // form is modal
        fsCreatedMDIChild,
        fsBorderStyleChanged,
        fsFormStyleChanged,
        fsFirstShow,  // form is shown for the first time
        fsDisableAutoSize

TFormState
- the set of form states that apply to this form
TModalResult
- the range of values that can be returned as a modal result
TModalResult
represents the value returned by a modal dialog. Even though the type is defined as an integer, instead a few standard constants are used as return results in applications.
TCustomForm
- the base type for TForm
FFormBorderStyle
- local variable to hold style of border
FActionLists
- local variable holding lists of actions asociated with the Form
CMShowingChanged
- system message method for showing if the form has changed
Activate
- method for rendering the Form active
ActiveChanged
- method for a form that is active and changed
BeginFormUpdate
- start updating the Form
CreateParams
calls inherited CreateParams, and specifically copies style from parent
TWinControl.CreateParams
CreateWnd
calls inherited CreateWnd, signals if a handle is required and attaches a menu to the window if one does not yet exist; activates focus if visible
TWinControl.CreateWnd TScrollingWinControl.CreateWnd
Deactivate
- method for rendering the Form inactive
DoClose
- close the Form using the specified CloseAction
DoCreate
- perform the Create action
DoDestroy
- perform the Destroy action
DoHide
- method for hiding a previously visible object
DoShow
- method to redender visible a previously hidden form
EndFormUpdate
- finish updating the Form
GetChildren
calls inherited GetChildren then takes ownership of all components, including those without parents
TComponent.GetChildren TWinControl.GetChildren
Loaded
- calls inherited Loaded, makes this the active control and gives it focus
TComponent.Loaded TScrollingWinControl.Loaded
ChildHandlesCreated
- method for use when handles have been created for descendants
TWinControl.ChildHandlesCreated
Notification
calls inherited Notification then add or removes the component's action list (depending on what Operation specifies)
TComponent.Notification
SetZOrder
- set the Z order for the Form; if Topmost is True, Form is on top of all other objects
UpdateShowing
- method to update the Visible property
TWinControl.UpdateShowing
DoFirstShow
- perform the first Show action since creation of the Form
UpdateWindowState
- update the state of the Window displaying the Form
VisibleChanging
- method for dealing with a Form whose Visible property is changing
WndProc
- performs actions specific to the message then calls inherited WndProc

WndProc - performs actions specific to the message then calls inherited WndProc

Specific messages include:

Activate, SetFocus. KillFocus; Exit, Enter; Window Position Changing; Draw Item

TControl.WndProc TWinControl.WndProc
VisibleIsStored
- True if the Visible property has been stored
GetDefaultDockCaption
- returns the default caption to be used for docking
CMActionExecute
- system message method for executing action
CMActionUpdate
- system message method for updating action
Asks every visible control to Execute the specified action ExeAction.

DoExecuteAction asks every visible control to Execute the specified action ExeAction. If some control executes it and returns true, then the traversal of visible components is stopped. All child controls (and its children etc) are queried too.

For example you have

TForm TPanel TButton TCheckBox TMemo

then the following controls are queried in this order: TPanel, TButton, TCheckBox, TMemo.

But first of all, the Form itself and the ActiveControl are asked to execute the given action.

True, if any control handles the action.
Action to execute.
DoUpdateAction
- asks all visible controls to update the specified action
DoExecuteAction
UpdateActions
- method for updating actions
Create
- constructor for TCustomForm: checks for correct ClassType, looks for required resources then creates the Form
This constructor can override the constructor of an ancestor class
TScrollingWinControl.Create
CreateNew
- constructor for creating a completely new form
BeforeDestruction
- method to be applied before Form is destroyed (usually involves clean-up)
Find the handle for the Icon
Destroy
- destructor for TCustomForm: frees all menus, icons, actionlists, screens and handlers, then performs inherited Destroy
TScrollingWinControl.Destroy
Is the associated query to be closed?
Set free the resources of the form
Shows this form as the top (nearest) item of any stack of windows or images.
Ensure that this form is always visible, if necessary moving it to the top (front) of the stack of images
WantChildKey
- returns True if the specified child control requires a key (Message)
DefocusControl
- withdraws focus from the specified control, removing it if required
SetFocusedControl
- method for giving focus to specified control; returns True if successful
FocusControl
- giving focus to specified control, automatically bringing form to front
If the control or one of its parents is not visible or disabled an exception will be raised.
Show this form as modal - ie control cannot be resumed by another form until the current form is closed
SetRestoredBounds
- set the bounds defining the position of the restored control
GetRolesForControl
- returns a set of roles (default, cancel) for the Form
AddHandlerFirstShow
- perform the action for adding a handler at the time of first showing
RemoveHandlerFirstShow
- perform the action for removing the handler on the first showing
AddHandlerClose
- adds a handler for closing Form
RemoveHandlerClose
- removes handler for closing form
AddHandlerCreate
- performs the OnCreateHandler event
RemoveHandlerCreate
- removes the handler for the Create event
IsShortcut
- if True, the specified Key and Message are active as a shortcut
IntfDropFiles
- Invokes OnDropFilesEvent of the form. This function is called by the interface.
IntfHelp
- Show help for control or menu item. This function is called by the interface.
Is true when the form has the focus
Use active to check if the form has the focus
Specifies the active control on the form
Use this to get or set the active control on this form
Specifies the active default control on the Form
Specifies if files are allowed to be dropped on this form.
Set AllowDropFiles event to True to allow dropping files on this form. It is set to False by default.
Specifies which icons appear on the top of the form
Use bordericons flags to get or set the icons that appear on the top border of the form.

By default we see down-triangle or other generic icon on the left,

which activates a pop-up system menu allowing closure or re-sizing of the form,

and on the right end we see the minimise and re-size/maximise buttons,

but of course these can be customised by the application programmer.
The border style for this Form

Use borderstyle to get or set the appearance of the form's border.

By default it is a sizeable window, but it could, for example, be a dialog form or a tool window, or could be non-sizeable

This property is slightly different (has a differert base type) from the TCustomControl.BorderStyle When the form is put into another control the window borders depend on the widgetset. There are no borders under gtk.

The control associated with the cancel action

Determines the control associated with the Cancel action (exit from the control without changing anything).

This is usually a button with the caption 'Cancel', but might be an 'Exit' button or anything else the application programmer decides.

This control is selected either by explicitly clicking with the mouse, or by hitting the 'Esc' key

The form's colour; by default it is the same as the colour specified for button faces.
The control associated with the default action for this form
Reads or sets a flag determining the default control.

This is typically a button such as 'Accept' which is highlighted in some way on-screen to indicate that this is the default action, and is selected either by hitting 'Return' or 'Enter' or by selecting that control with the mouse
Determines the state of the form
Reads or writes a flag to determine the form's state:

is it being created, is this its first showing, is the border style being changed, etc.

FormState is a set, so could take zero or more of possible values.
Determinates the style of the form

Reads or writes flag to determine the style of the form.

Default is 'normal', but could be MDIChild or MDINormal, could stay on top or could be a 'Splash' form.

FormStyle is a set, so could take zero or more of these values.

Specifies the help file that is used by the form
Reads or writes a flag to determine identity of Help file,

and to determine whether its name is stored.

Property contains filename as a string.
The Icon associated with this Form (which may appear in menus, directories, ListBoxes etc)
KeyPreview
- if True, Key Preview is possible
Specifies a MainMenu for this form
Drop a TMainMenu on the form and select it here to show it on the form.
Specifies the return value of an modal form
Reads or writes a flag to determine whether there is a modal resut.

If the form is modal, returns an integer value.
Event handler for activation (opening) of the form
Event handler for closing the form
Event handler for closing the query associated with the form
Event handler for creating the form
Event handler for deactivating the form
Event handler when the form is being destroyed
The event invoked when file is dropped on this form.
The OnDropFiles event is invoked when user drops one or multiple files on this form. You enable this feature by setting AllowDropFiles property.
Event handler when Help is required
Event handler if form is being hidden
Event handler if shortcut key is pressed
Event handler if form is to be shown
Event handler for a change in the window state
The scaling of the form in absolute terms

Reads or writes a flag to determine the scaling factor (a longinteger).

Not normally stored locally

The position of the form on the screen
Reads or writes a flag to determine screen position of form.

By default it is in the position that it was placed in the Form Designer
The position of the left edge of the form when it is restored (ie changes from minimised or maximised)
The position of the top edge of the form when it is restored (ie changes from minimised or maximised)
The width of the form when it is restored (ie changes from minimised or maximised)
The height of the form when it is restored (ie changes from minimised or maximised)
Should the form be shown in the system Task Bar?
Set or get this to set the form visible/hidden or get the status of the form
Represents how the form appears on the screen
Reads or write flag to determine state of the window on screen.

Default is 'normal' (ie not minimised or maximised)
TCustomFormClass
- class of TCustomForm
The operating system handle for the client
Use active control to set or get the control that has the focus on this form
TFormClass
- class of TForm
TCustomDockForm
- Base class for docking forms
Create
- constructor for TCustomDockForm: performs CreateNew then initialises autoscroll and style properties
TCustomForm.Create
Hint Window - the popup box containing helpful information that appears when the mouse pointer hovers over an object
Create
- constructor for THintWindow: performs inherited Create then initialises many properties including timers, styles, position, font and colour
TCustomForm.Create
Destroy
- destructor for THintWindow: frees timers then performs inherited Destroy
TCustomForm.Destroy
Allow the hint message to be displayed in the specified rectangular space
Allow the hint message to be displayed, with a pointer to further data
Work out the size of the rectangle required to display the specified hint message
Release the handle for the hint message and return it to the system
Does the hint disappear (get hidden) after a while?
If AutoHide is TRUE, the hint disappears afer an interval specified by HideInterval
The time after which the displayed hint disappears
THintWindowClass
- class of THintWindow
Screen - the visible area
Specifies which style the form border has
GetHintFont
- find the correct font for displaying Hints
TComponent.Create TLCLComponent.Create
Create
- constructor for TScreen: performs inherited Create then creates and initialises lists of fonts, strings and forms
TComponent.Destroy TLCLComponent.Destroy
Destroy
- destructor for TForm: frees various lists then performs inherited Destroy
The Index number of a Custom Form on the screen
The Index number of the Custom Form, stored as an integer
The Custom Form to which the Index refers
The index number of a Form on the Screen
The index number of the Form, stored as an integer
The Form to which the Index refers
CustomFormZIndex
- the index value of the form in the Z dimension (Front to Back)
MoveFormToFocusFront
- move the specified form to the front of the focus
MoveFormToZFront
- move form to front in the Z-plane (does not specify whether focused)
GetCurrentModalForm
- returns the current Modal form on the current screen (ie a form that is awaiting a user response)
GetCurrentModalFormZIndex
- returns the Z-plane index of the current modal form
CustomFormBelongsToActiveGroup
- returns True if the specified form belongs to the active group
FindForm
- returns the form with the specified name
Method for updating screen
AddHandlerFormAdded
- method for adding a form-adding handler
RemoveHandlerFormAdded
- method for removing a form-adding handler
AddHandlerRemoveForm
- method for adding a form-removing handler
RemoveHandlerRemoveForm
- method for removing a form-removing handler
AddHandlerActiveControlChanged
- method for adding a handler for a change in the active control
RemoveHandlerActiveControlChanged
- method for removing a handler for a change in the active control
AddHandlerActiveFormChanged
- method for adding a handler for a change in active form
RemoveHandlerActiveFormChanged
- method for removing a handler for a change in active form
The identity of the active control on this screen
Reads a flag to determine the active control
The identity of the active Custom Form on this screen
Reads a flag to determine the active Custom Form
The identity of the active Form on this Screen
Reads a flag to determine the active Form
The cursor currently being used in this screen
Reads or writes a flag to determine the cursor.

This can take any integer value, but there are several pre-determined cursor styles

listed as constants in 'Controls',

and these should be used to define the cursor for the current screen
The indexed list of available cursors for this screen
The number of Custom Forms on this screen
Reads flag to determine number of Custom Forms (integer)
The list of Custom Forms on the screen
CustomFormZOrderCount
- the number of forms arranged in Z-plane order (ie Front to Back)
CustomFormsZOrdered
- the forms arranged in Z-plane order (ie Front to Back)
The total available height of the desktop in which the screen is to be placed
The total available width of the desktop in which the screen is to be placed
FocusedForm
- the form that holds Focus
The number of Forms on this screen
Reads a flag to determine the number of Forms (integer)
The list of Forms in this Screen
Index number of a Form, stored as an integer
The fonts to be used in this screen
Reads a flag to determine the fonts to be used; their names are stored as a list of strings
The height of the screen
Reads a flag to determine screen height; stored as an integer
The font to be used to display hints
Reads a flag to determine the font to be used (font name stored as a string)
The width of the screen
Reads flag to determine screen width, stored as an integer
Event handler for change in the active control
Event handler for a change in the active form on the screen
Scaling factor for displaying graphic information on the screen
Reads a flag to determine number of pixels per inch (integer)
TApplication
- the whole current program, described as an object

TApplication - the whole current program, described as an object.

Includes the useful function MessageBox, a simple dialog intended for displaying error messages internally, but available as an alternative to the various Message Dialogs

Make the application run in a loop, ie it starts again when it has finished
GetConsoleApplication
- returns True if this is a Console application (ie text-mode, non-GUI)
NotifyIdleHandler
- method for sending message to Idle handler (sends True if process is done)
NotifyIdleEndHandler
- method for sending message to handler for end of idle state
NotifyActivateHandler
- method for sending message to handler for activation
NotifyDeactivateHandler
- method for sending message to handler for deactivation
IsHintMsg
- returns True if specified message is a valid Hint
DoOnMouseMove
- method for the OnMouseMove event
ShowHintWindow
- method for showing a hint window
OnHintTimer
- event handler for timing the duration of hints
SetTitle
- method for writing the specified title string to local store
StartHintTimer
- method for starting the timer for display of a hint message
UpdateVisible
- update all visible components
DoIdleActions
- perform the actions that remain idle
MenuPopupHandler
- method for dealing with menu popups
ProcessAsyncCallQueue
- method to process a queue of asynchronous calls
FreeComponent
- method for freeing a component
DoBeforeFinalization
- the things to be done before finalisation of the application
This instance of the constructor performs most of the setting up of the environment for the application. The instances of Create that occur in some of the ancestor classes are place holders rather than actual instructions for constructing the object
TCustomApplication.Create
Create
- constructor for TApplication: initialises a large number of local variables and properties, then calls inherited Create
The Owner object that invoked this instance of TApplication
TCustomApplication.Destroy
Destroy
- destructor for TApplication: frees various handles and flags, then cals inherited Destroy
Method for dealing with a control that has been destroyed
BringToFront
- Use the selected widget set's method to bring the application's form(s) to the front
Create Form or any other kind of component
Note: The name is confusing and only kept for Delphi compatibility.

It can actually create any kind of component

Creates a Component instance, sets the pointer to the component variable and loads the component.

If it is a form it will be added to the application's forms list
UpdateMainForm
- update the Application's main form
Insert a given asynchronous call into the queue
The method to be used for the asynchronous call
The data structure used by the asynchronous call method
ReleaseComponent
- method to release the specified component
This is a function that should be supplied by the application programmer, to override the placeholders declared in ancestor classes
TComponent.ExecuteAction
ExecuteAction
- calls the OnActionExecute event hndler if it is assigned
UpdateAction
- calls the OnUpdateAction event handler if it is assigned
TComponent.UpdateAction
Individual exception handler methods should be supplied by the application programmer, to override place-holder entries declared in ancestor classes.

This method checks whether the application is required to halt if an exception occurs, or invokes the appropriate handler.

It also writes details of the exception to the appropriate place for debugging.
TCustomApplication.HandleException
HandleException
method for handling an exception; attempts to maintain program execution if possible, otherwise exits gracefully
Process all events according to the method defined for the widget set
HelpContext
- returns True if there is a specified context-dependent help message associated with the application, with an optionally specified position
HelpKeyword
- returns True if there is a specified help keyword associated with the application, with an optionally specified position
ShowHelpForObject
- method for displaying help messages
HideAllFormsWithStayOnTop
- hide all forms, but keep the curent top form on top
IsWaiting
- returns True if the application is awainting an event
Cancels a request for a hint, if there is no hint timer or no hint to display
Don't display the hint
HintMouseMessage
- method to find the hint for the control at the mouse position
The icon to be associated with this application
Finds the appropriate widget set, reads the application's icon (if any) from the Lazarus Resource file, initialises the screen, and leaves it ready for processing.
TCustomApplication.Initialize
Initialize
- calls inherited Initialize, then initialises widget set, loads icons from Laz resources and updates screen
Message Box
: a useful function to display a message.

MessageBox: a useful function to display a message.

The function is used internally to display messages during the handling of Exceptions , but is also available to application programmers as an alternative to some of the message dialogs found in Dialogs

The argument Flags is a long integer constructed by adding together various constants to define the contents and behaviour of the box, for example:

MB_ABORTRETRYIGNORE + MR_ICONQUESTION will cause the application to display a query (?) icon in a box with three buttons:

ABORT RETRY IGNORE.

The following button constants are available:

MB_OK

MB_OKCANCEL

MB_ABORTRETRYIGNORE

MB_YESNOCANCEL

MB_YESNO

MB_RETRYCANCEL

And the following icon constants:

MB_ICONHAND

MB_ICONQUESTION

MB_ICONEXCLAMATION

MB_ICONASTERICK

MB_ICONWARNING = MB_ICONEXCLAMATION

MB_ICONERROR = MB_ICONHAND

MB_ICONSTOP = MB_ICONHAND

MB_ICONINFORMATION = MB_ICONASTERICK

These constants are declared on the LCLType unit.

The function returns an integer value corresponding to the button that was pressed; its value can be determined by reference to the constants [IDOK..IDHELP]

It can be invoked like a procedure call (ie as a 'MessageBox()' statement rather than as a 'Variable := MessageBox()' function call)

MessageDlg
Result
Result: integer value returned by the function to signify which box was selected

Can be one of the following values:

IDOK

IDCANCEL

IDABORT

IDRETRY

IDIGNORE

IDYES

IDNO

IDCLOSE

IDHELP
Text: the string that is displayed as a prompt or instruction in the Box
Caption: the string label at the top of the message box
Flags - a long integer constructed by adding together various constants to define the contents and behaviour of the box
Flags: longint - an integer constructed by adding together various constants to define the contents and behaviour of the box, for example

MB_ABORTRETRYIGNORE + MR_ICONQUESTION will cause the application to display a query (?) icon in a box with three buttons:
ABORT RETRY IGNORE.

The following button constants are available:

MB_OK

MB_OKCANCEL

MB_ABORTRETRYIGNORE

MB_YESNOCANCEL

MB_YESNO

MB_RETRYCANCEL

And the following icon constants:

MB_ICONHAND

MB_ICONQUESTION

MB_ICONEXCLAMATION

MB_ICONASTERICK

MB_ICONWARNING = MB_ICONEXCLAMATION

MB_ICONERROR = MB_ICONHAND

MB_ICONSTOP = MB_ICONHAND

MB_ICONINFORMATION = MB_ICONASTERICK

These constants are declared on the LCLType unit.
Minimise the form using the widget set's method
Restore the application's form to the size it was before minimisation or maximisation
Notification
if Operation is Remove, then sets any Component to nil, otherwise calls inherited Notification
TComponent.Notification
ProcessMessages
- method for processing system messages
Idle
- method for rendering the Application Idle if Wait is True
This method should be supplied by the application programmer, and should be the main process control procedure for the application
The exception that is to be displayed
DisableIdleHandler
- turn off the Idle handler
EnableIdleHandler
- turn on the Idle handler
NotifyUserInputHandler
- send message t handler for user input
NotifyKeyDownBeforeHandler
- send message to handler for the condition where a key has been previously pressed (eg a Shift, Control or Alt key(
NotifyKeyDownHandler
- sends message to handler for a key pressed down
ControlKeyDown
- method for dealing with the Control Key being pressed down
ControlKeyUp
- method for dealing with a released Control key
AddOnIdleHandler
- method for adding a handler for the Idle state
RemoveOnIdleHandler
- method for removing a handler for the Idle state
AddOnIdleEndHandler
- method to add a handler for the end of the Idle state
RemoveOnIdleEndHandler
- method for removing handler for the end of the Idle state
AddOnUserInputHandler
- method for adding a handler for user input
RemoveOnUserInputHandler
- method for removing handler for user input
AddOnKeyDownBeforeHandler
- method for adding handler for the state where a key (eg Ctrl, Shift, Alt) has been already pressed
RemoveOnKeyDownBeforeHandler
- method for removing handler for the state where a key (eg Ctrl, Shift, Alt) has been already pressed
AddOnKeyDownHandler
- method for adding a handler for the Key Down state
RemoveOnKeyDownHandler
- method for removing handler for the Key Down state
AddOnActivateHandler
- method for adding a handler for activation
RemoveOnActivateHandler
- method for removing handler for activation
AddOnDeactivateHandler
- method for adding handler for deactivation
RemoveOnDeactivateHandler
- method for removing deactivation handler
AddOnExceptionHandler
- method for adding exception handler
RemoveOnExceptionHandler
- method for removing exception handler
AddOnEndSessionHandler
- method for adding handler for end of session
RemoveOnEndSessionHandler
- method for removing handler for end of session
AddOnQueryEndSessionHandler
- method for adding handler for a query at the end of a session
RemoveOnQueryEndSessionHandler
- method for removing handler for a query at the end of a session
AddOnMinimizeHandler
- method for adding handler for minimising component
RemoveOnMinimizeHandler
- method to remove handler for maximising component
AddOnRestoreHandler
- method to add handler for Restore component
RemoveOnRestoreHandler
- method to remove restore handler
AddOnDropFilesHandler
- method to add handler for dropped files
RemoveOnDropFilesHandler
- method for removing drop files handler
AddOnHelpHandler
- method to add Help handler
RemoveOnHelpHandler
- method to remove Help handler
AddOnHintHandler
- method to add handler for Hints
RemoveOnHintHandler
- method to remove Hint handler
AddOnShowHintHandler
- method to add handler for showing Hints
RemoveOnShowHintHandler
- method for removing handler for showing Hints
RemoveAllHandlersOfObject
- method to remove all handlers of an object
DoBeforeMouseMessage
- things to be done before a mouse message is processed
IsShortcut
- returns True if specified Keyi s a shortcut
IntfQueryEndSession
- called by the interface when there is a query at the end of a session
IntfEndSession
- called by the interface at the end of a session
IntfAppMinimize
- called by the interface if an application is minimised
IntfAppRestore
- called by the interface when an application is being restored
IntfDropFiles
- called by the interface for dropping files
DoEscapeKey
- method for processing the Escape key
DoReturnKey
- method for processing the Return (Enter) key
DoTabKey
- method for processing the Tab key
Active
- returns True if this is an active Application
CaptureExceptions
- If exceptions have occurred, find out what they are, ready for processing
FindGlobalComponentEnabled
- returns True if the Find Global Component state is enabled
Flags
- the list of flags for this application
The hint associated with the main application
A hint is a small pop-up mesage that appears briefly while the mouse hovers over a specified area of the screen. It usually displays useful information about how to use an object or what data should be entered, etc

Reads or writes a flag to determine the hint associated with the application
The colour used to display the hint
The delay period after mouse entry before the hint becomes visible
HintHidePausePerChar
- the pause period per character for hiding a hint
HintPause
- The length of time for which the hint is displayed
HintShortCuts
- If True, there are hints for short cut keys
HintShortPause
- the pause before a shortcut hint is displayed
Determine how the form is to be navigated
Reads or writes a flag to determine the navigation method:

Is Tab used to move to next control?

Does Enter or Ret activate the default action?

Does Esc perform the cancel action?

Does F1 activate a Help system?

Navigation Options is a set, so can take zero or more of the available values
The Main Form used by the application for process control and for data input/output
Reads a flag to get particulars of the main form
OnActionExecute
- event handler for executing the application's main action
OnActionUpdate
- event handler for updating the application's main action
OnActivate
- Event handler for activation of the application
OnDeactivate
- Event handler for deactivation of the application
OnIdle
- event handler for the Idle state
OnIdleEnd
- event handler for the end of the Idle state
OnEndSession
- Event handler for ending a session of the application
OnQueryEndSession
- event handler for processing a query at the end of a session
OnMinimize
- Event handler for minimising the application's form
OnRestore
- Event handler for restoring the application's form from minimised or maximised condition
OnDropFiles
- The event invoked when file is dropped on one of the application forms.
The OnDropFiles event is invoked when user drops one or multiple files on one of the application forms. You must enable this feature by setting AllowDropFiles property of form.
OnHelp
- Event handler when help is required
OnHint
- Event handler when a hint is required
OnShortcut
- Event handler when a shortcut key is pressed
OnShowHint
- Event handler for showing a hint
OnUserInput
- Event handler when user input is required or is occurring
OnDestroy
- Event handler for destruction of the application
ShowHint
- Is a hint required to be shown?
ShowMainForm
- Is the main form for the application to be shown? Default TRUE
ApplicationType
- The type of the application (ie the sort of device for which it is intended)

The type of the application:

Default, Desktop, Handheld, PDA, Smartphone

TApplicationProperties
: The properties of the current application

TApplication Properties can be set as a local default set of properties to be used for any new instance fo TApplication

SetCaptureExceptions
- specifies whether exceptions are to be captured
SetHelpFile
- specifies which file is to be used for Help messages
SetHint
- specifies the text for a Hint
SetHintColor
- specifies the colour for displaying hints
SetHintHidePause
- specifies the length of pause before a hint becomes hidden
SetHintPause
- specifies the length of pause before a hint is displayed
SetHintShortCuts
- specifies whether hints are to be displayed for Shortcut keys
SetHintShortPause
- specifies the length of pause before a shortcut key hint is displayed
SetShowHint
- specifies whether hints are to be displayed
SetTitle
- specifies the title for the Form
SetOnException
- specifies the event handler for exceptions
SetOnIdle
- specifies the handler for Idle events
SetOnIdleEnd
- specifies the handler to notify the end of an idle period
SetOnEndSession
- specifies the event handler to notify the end of a session
SetOnQueryEndSession
- specify the event handler for a query at the end of a session
SetOnMinimize
- specify the event handler for minimising the application form
SetOnRestore
- specify the event handler for restoring the application's form
SetOnDropFiles
- specify the event handler for dropping files
SetOnHelp
- specify the event handler for help requests
SetOnHint
- specify the event handler for a request to show hints
SetOnShowHint
- specify the event handler for showing hints
SetOnUserInput
- specify the event handler for dealing with User input
Create
- constructor for TApplicationProperties: calls inherited Create, then sets some defaults if new application is being designed, or loads local values from existing application
TComponent.Create TLCLComponent.Create
Destroy
- destructor for TApplicationProperties: removes a number of handlers then calls inherited Destroy
TComponent.Destroy TLCLComponent.Destroy
CaptureExceptions
- Determine whether exceptions are being captured
Boolean property (true if exceptions are being captured); reads or writes flag to see if they are being captured
HelpFile
- Determines which file to use for Help
Reads or writes flag to determine name of Help file - name is stored as a string
Hint
- Determines Hint to be used
Reads or writes flag to determine Hint - stored as a string
HintColor
- Colour to be used when displaying Hint
Reads or writes flag to determine Hint colour (stored as a TColor integer)
HintHidePause
- the length of pause before a hint becomes hidden
HintPause
- the length of pause before a hint is displayed
HintShortCuts
- the hints for shortcut keys (present if True)
HintShortPause
- the length of pause before a shortcut hint is displayed
ShowHint
- Determines whether a hint is to be displayed
Read or write flag to determine whether to display hint (stored as boolean, True if hint is to be displayed)
ShowMainForm
- Determines whether main form is to be displayed
Title
to be shown in Application's top Border
OnException
- Event handler for exceptions
OnIdle
- event handler for the Idle state
OnIdleEnd
- event handler for the end of the Idle state
OnEndSession
- Event handler for the end of the session
OnQueryEndSession
- Event handler for a query at the end of a session
OnMinimize
- Event handler for minimising the form
OnRestore
- Event handler for restoring a form which has been minimised or maximised
OnDropFiles
- Event handler when files are dropped on the form
OnHelp
- Event handler when help is needed
OnHint
- Event handler when a hint is needed
OnShowHint
- Event handler for showing a hint
OnUserInput
- Event handler when user input is received
IsDesignMsg
- receives a message from Sender, and returns True if it is a design message
Method when design is Modified
Notification
that the suppied Operation has been applied to the specified Component
PaintGrid
- method for painting the grid in the designer
ValidateRename
- method to validate the Rename process
GetShiftState
- returns the value of the shift state (whether shifted, Cntl key, Alt key etc)
SelectOnlyThisComponent
- method to select only the currrent component in the designer
UniqueName
- returns a Unique name for the designer, using the BaseName as a starting point
TFormPropertyStorage
- class for storage of a Form's properties
Data Module
Data Module: for interfacing to the database
KeysToShiftState
- converts an actual physical key code to a shift state (ie Shift, Ctrl, Alt etc)
KeyDataToShiftState
- converts Key data to a shift state
WindowStateToStr
- converts a Window state to a string
StrToWindowState
- converts a string to a Window state
TMessageBoxFunction
- the function to be used by a message box: specifies Text and Flags, and returns an integer value
The version of the LCL as string. Used to distinguish form streams of different versions.
TComponent.Loaded
The number of data modules on the screen
The list of Data Modules
DefineProperties
- calculates low and high values for frame design from ancestor class
TComponent.DefineProperties TControl.DefineProperties
BigIconHandle
- returns system Handle for large Icon
SmallIconHandle
- returns system Handle for small Icon
GetFormImage
- gets a Bitmap image for the Form
FindDataModule
- returns the Data Module with the specified name
GetParams
- find the application's parameters (typically by parsing the command line that invoked the application)
BigIconHandle
- system Handle for large Icon
SmallIconHandle
- system handle for small Icon
BidiMode
- whether bi-directional mode is available
DoShowWindow
automatically choose a control to focus
AdjustClientRect
- adjusts window size to accommodate borders
TWinControl.AdjustClientRect
DisableForms
- disable all forms except SkipForm. If DisabledList is available then add forms to that list and return it, otherwise return new list. Used to show forms and other dialogs modal
EnableForms
- enable all forms from AFormList and destroy list. Used to restore state after DisableForms
DoArrowKey
- method for processing an arrow key
ShowButtonGlyphs
- determines whether to show show or not glyphs on TBitBtn controls
This option allows to set rule for all application TBitBtn controls which have GlyphShowMode = gsmApplication.

Different operation systems has different preferences regards showing button glyphs. Mac OS X and Windows UI guidlines suggests not to use them. Gnome has a special theme setting for this. sbgSystem option allows application to use system preferences for glyphs showing. sbgAlways is the default value because of Delphi compatibility.
ShowMenuGlyphs
- Deturmines whether show or not glyphs in menu
This option allows to set rule for all application TMenuItem components which have GlyphShowMode = gsmApplication.

Different operation systems has different preferences regards showing images in menus. Mac OS X suggests not to use them. Gnome has a special theme setting for this. sbgSystem option allows application to use system preferences for menu icons showing. sbgAlways is the default value because of Delphi compatibility.
TApplicationShowGlyphs
- enumerated type to describe the glyphs showing rule - whether to show them always, never or depends on system settings

sbgAlways - show glyphs always (inspite of system preferences)

sbgNever - show glyphs never (inspite of system preferences)

sbgSystem - use system preferences for glyphs showing

TMonitor
- system monitor
TMonitor contains properties to access visible and work dimensions of the system monitor.
Hanlde
- system handle of monitor
MonitorNum
- index of the monitor in the screen monitors list
Left
- the logical position of the left side of the monitor
Height
- the logical height of the monitor
Top
- the logical position of the top side of the monitor
Width
- the logical width of the monitor
BoundsRect
- the logical dimensions of the monitor
WorkareaRect
- the logical dimensions of the monitor except the unusable parts (like the taskbar, the dockbar, the global menu)
Primary
- indicates whether this monitor is primary
TMonitorList
- a list of monitors
MonitorCount
- returns a number of monitors
Monitors
- provides access to the monitor list array
PrimaryMonitor
- return the primary monitor of the system
Monitor
- returns the monitor on which the form is mostly places (the biggest form area is placed)
TDefaultMonitor
- enumerated type to specify on which monitor to place the form
dmDesktop - don't change the form position (use the full desktop) dmPrimary - place the form on the primary monitor dmMainForm - place the form on the same monitor as the main form. If there is no main form then use dmPrimary behavior. dmActiveForm - place the form on the same monitor as the current active form. If there is no active form use dmMainForm behavior.