BlitzMax/Modules/Events/Events

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Event objects are used to notify your application about external events such as user input, user interface activity and so on.

The are two main ways your program can receive events: either by adding a hook function to the EmitEventHook hook, or by using using the global event queue

The most important field in an event object is the id field, which identifies the kind of event:

Event id Description
EVENT_APPSUSPEND Application suspended
EVENT_APPRESUME Application resumed
EVENT_APPTERMINATE Application wants to terminate
EVENT_KEYDOWN Key pressed. Event data contains keycode
EVENT_KEYUP Key released. Event data contains keycode
EVENT_KEYCHAR Key character. Event data contains unicode value
EVENT_MOUSEDOWN Mouse button pressed. Event data contains mouse button code
EVENT_MOUSEUP Mouse button released. Event data contains mouse button code
EVENT_MOUSEMOVE Mouse moved. Event x and y contain mouse coordinates
EVENT_MOUSEWHEEL Mouse wheel spun. Event data contains delta clicks
EVENT_MOUSEENTER Mouse entered gadget area
EVENT_MOUSELEAVE Mouse left gadget area
EVENT_TIMERTICK Timer ticked. Event source contains timer object
EVENT_HOTKEYHIT Hot key hit. Event data and mods contains hotkey keycode and modifier
EVENT_MENUACTION Menu has been selected
EVENT_WINDOWMOVE Window has been moved
EVENT_WINDOWSIZE Window has been resized
EVENT_WINDOWCLOSE Window close icon clicked
EVENT_WINDOWACTIVATE Window activated
EVENT_WINDOWACCEPT Drag and Drop operation was attempted
EVENT_GADGETACTION Gadget state has been updated
EVENT_GADGETPAINT A Canvas Gadget needs to be redrawn
EVENT_GADGETSELECT A TreeView Node has been selected
EVENT_GADGETMENU User has right clicked a TreeView Node or TextArea gadget
EVENT_GADGETOPEN A TreeView Node has been expanded
EVENT_GADGETCLOSE A TreeView Node has been collapsed
EVENT_GADGETDONE An HTMLView has completed loading a page

Globals[edit]

EmitEventHook[edit]

Global EmitEventHook=AllocHookId()

Description: Hook id for emitted events

Information: The EmitEventHook global variable contains a hook id for use with AddHook.

Each time EmitEvent is called, the event is passed to all EmitEventHook hook functions by means of the hook function data parameter.

Types[edit]

TEvent[edit]

Event object type

Fields
  • id
  • source
  • data
  • mods
  • x
  • y
  • extra
Methods
  • Emit
  • ToString
Functions
  • Create
  • AllocUserId

TEvent: Fields[edit]

id

Field id

Description: Event identifier

source

Field source:Object

Description: Event source object

data

Field data

Description: Event specific data

mods

Field mods

Description: Event specific modifiers

x

Field x

Description: Event specific position data

y

Field y

Description: Event specific position data

extra

Field extra:Object

Description: Event specific extra information

TEvent: Methods[edit]

Emit

Method Emit()

Description: Emit this event

Information: This method runs all EmitEventHook hook function, passing Self as the hook data.

ToString

Method ToString$()

Description: Convert event to a string

Information: This method is mainly useful for debugging purposes.

TEvent: Functions[edit]

Create

Function Create:TEvent( id,source:Object=Null,data=0,mods=0,x=0,y=0,extra:Object=Null )

Description: Create an event object

Returns: A new event object

AllocUserId

Function AllocUserId()

Description: Allocate a user event id

Returns: A new user event id

Functions[edit]

EmitEvent[edit]

Function EmitEvent( event:TEvent )

Description: Emit an event

Information: Runs all EmitEventHook hooks, passing event as the hook data.

CreateEvent[edit]

Function CreateEvent:TEvent( id,source:Object=Null,data=0,mods=0,x=0,y=0,extra:Object=Null )

Description: Create an event object

Returns: A new event object

AllocUserEventId[edit]

Function AllocUserEventId( description$="" )

Description: Allocate a user event id

Returns: A new user event id