| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
SDL.Event
Contents
Description
SDL.Event exports an interface for working with the SDL event model. Event handling allows your application to receive input from the user. Internally, SDL stores all the events waiting to be handled in an event queue. Using functions like pollEvent and waitEvent you can observe and handle waiting input events.
The event queue itself is composed of a series of Event values, one for each waiting event. Event values are read from the queue with the pollEvent function and it is then up to the application to process the information stored with them.
Synopsis
- pollEvent :: MonadIO m => m (Maybe Event)
- pollEvents :: (Functor m, MonadIO m) => m [Event]
- mapEvents :: MonadIO m => (Event -> m ()) -> m ()
- pumpEvents :: MonadIO m => m ()
- waitEvent :: MonadIO m => m Event
- waitEventTimeout :: MonadIO m => CInt -> m (Maybe Event)
- data RegisteredEventType a = RegisteredEventType {
- pushRegisteredEvent :: a -> IO EventPushResult
- getRegisteredEvent :: Event -> IO (Maybe a)
- data RegisteredEventData = RegisteredEventData {
- registeredEventWindow :: !(Maybe Window)
- registeredEventCode :: !Int32
- registeredEventData1 :: !(Ptr ())
- registeredEventData2 :: !(Ptr ())
- data EventPushResult
- emptyRegisteredEvent :: RegisteredEventData
- registerEvent :: MonadIO m => (RegisteredEventData -> Timestamp -> IO (Maybe a)) -> (a -> IO RegisteredEventData) -> m (Maybe (RegisteredEventType a))
- type EventWatchCallback = Event -> IO ()
- data EventWatch
- addEventWatch :: MonadIO m => EventWatchCallback -> m EventWatch
- delEventWatch :: MonadIO m => EventWatch -> m ()
- data Event = Event {}
- type Timestamp = Word32
- data EventPayload
- = WindowShownEvent !WindowShownEventData
- | WindowHiddenEvent !WindowHiddenEventData
- | WindowExposedEvent !WindowExposedEventData
- | WindowMovedEvent !WindowMovedEventData
- | WindowResizedEvent !WindowResizedEventData
- | WindowSizeChangedEvent !WindowSizeChangedEventData
- | WindowMinimizedEvent !WindowMinimizedEventData
- | WindowMaximizedEvent !WindowMaximizedEventData
- | WindowRestoredEvent !WindowRestoredEventData
- | WindowGainedMouseFocusEvent !WindowGainedMouseFocusEventData
- | WindowLostMouseFocusEvent !WindowLostMouseFocusEventData
- | WindowGainedKeyboardFocusEvent !WindowGainedKeyboardFocusEventData
- | WindowLostKeyboardFocusEvent !WindowLostKeyboardFocusEventData
- | WindowClosedEvent !WindowClosedEventData
- | KeyboardEvent !KeyboardEventData
- | TextEditingEvent !TextEditingEventData
- | TextInputEvent !TextInputEventData
- | KeymapChangedEvent
- | MouseMotionEvent !MouseMotionEventData
- | MouseButtonEvent !MouseButtonEventData
- | MouseWheelEvent !MouseWheelEventData
- | JoyAxisEvent !JoyAxisEventData
- | JoyBallEvent !JoyBallEventData
- | JoyHatEvent !JoyHatEventData
- | JoyButtonEvent !JoyButtonEventData
- | JoyDeviceEvent !JoyDeviceEventData
- | ControllerAxisEvent !ControllerAxisEventData
- | ControllerButtonEvent !ControllerButtonEventData
- | ControllerDeviceEvent !ControllerDeviceEventData
- | AudioDeviceEvent !AudioDeviceEventData
- | QuitEvent
- | UserEvent !UserEventData
- | SysWMEvent !SysWMEventData
- | TouchFingerEvent !TouchFingerEventData
- | TouchFingerMotionEvent !TouchFingerMotionEventData
- | MultiGestureEvent !MultiGestureEventData
- | DollarGestureEvent !DollarGestureEventData
- | DropEvent !DropEventData
- | ClipboardUpdateEvent
- | UnknownEvent !UnknownEventData
- newtype WindowShownEventData = WindowShownEventData {}
- newtype WindowHiddenEventData = WindowHiddenEventData {}
- newtype WindowExposedEventData = WindowExposedEventData {}
- data WindowMovedEventData = WindowMovedEventData {}
- data WindowResizedEventData = WindowResizedEventData {}
- data WindowSizeChangedEventData = WindowSizeChangedEventData {}
- newtype WindowMinimizedEventData = WindowMinimizedEventData {}
- newtype WindowMaximizedEventData = WindowMaximizedEventData {}
- newtype WindowRestoredEventData = WindowRestoredEventData {}
- newtype WindowGainedMouseFocusEventData = WindowGainedMouseFocusEventData {}
- newtype WindowLostMouseFocusEventData = WindowLostMouseFocusEventData {}
- newtype WindowGainedKeyboardFocusEventData = WindowGainedKeyboardFocusEventData {}
- newtype WindowLostKeyboardFocusEventData = WindowLostKeyboardFocusEventData {}
- newtype WindowClosedEventData = WindowClosedEventData {}
- newtype SysWMEventData = SysWMEventData {}
- data KeyboardEventData = KeyboardEventData {}
- data TextEditingEventData = TextEditingEventData {}
- data TextInputEventData = TextInputEventData {}
- data MouseMotionEventData = MouseMotionEventData {}
- data MouseButtonEventData = MouseButtonEventData {}
- data MouseWheelEventData = MouseWheelEventData {}
- data JoyAxisEventData = JoyAxisEventData {}
- data JoyBallEventData = JoyBallEventData {}
- data JoyHatEventData = JoyHatEventData {}
- data JoyButtonEventData = JoyButtonEventData {}
- data JoyDeviceEventData = JoyDeviceEventData {}
- data ControllerAxisEventData = ControllerAxisEventData {}
- data ControllerButtonEventData = ControllerButtonEventData {}
- data ControllerDeviceEventData = ControllerDeviceEventData {}
- data AudioDeviceEventData = AudioDeviceEventData {}
- data UserEventData = UserEventData {
- userEventType :: !Word32
- userEventWindow :: !(Maybe Window)
- userEventCode :: !Int32
- userEventData1 :: !(Ptr ())
- userEventData2 :: !(Ptr ())
- data TouchFingerEventData = TouchFingerEventData {}
- data TouchFingerMotionEventData = TouchFingerMotionEventData {}
- data MultiGestureEventData = MultiGestureEventData {}
- data DollarGestureEventData = DollarGestureEventData {}
- newtype DropEventData = DropEventData {}
- newtype UnknownEventData = UnknownEventData {}
- data InputMotion
- data MouseButton
Polling events
pollEvent :: MonadIO m => m (Maybe Event) #
Poll for currently pending events. You can only call this function in the thread that set the video mode.
pollEvents :: (Functor m, MonadIO m) => m [Event] #
Clear the event queue by polling for all pending events.
mapEvents :: MonadIO m => (Event -> m ()) -> m () #
Run a monadic computation, accumulating over all known Events.
This can be useful when used with a state monad, allowing you to fold all events together.
pumpEvents :: MonadIO m => m () #
Pump the event loop, gathering events from the input devices.
This function updates the event queue and internal input device state.
This should only be run in the thread that initialized the video subsystem, and for extra safety, you should consider only doing those things on the main thread in any case.
pumpEvents gathers all the pending input information from devices and places it in the event queue. Without calls to pumpEvents no events would ever be placed on the queue. Often the need for calls to pumpEvents is hidden from the user since pollEvent and waitEvent implicitly call pumpEvents. However, if you are not polling or waiting for events (e.g. you are filtering them), then you must call pumpEvents to force an event queue update.
See SDL_PumpEvents for C documentation.
Wait until the specified timeout for the next available amount.
Registering user events
data RegisteredEventType a #
A user defined event structure that has been registered with SDL.
Use registerEvent, below, to obtain an instance.
Constructors
| RegisteredEventType | |
Fields
| |
data RegisteredEventData #
A record used to convert between SDL Events and user-defined data structures.
Used for registerEvent, below.
Constructors
| RegisteredEventData | |
Fields
| |
Instances
data EventPushResult #
Possible results of an attempted push of an event to the queue.
Constructors
| EventPushSuccess | |
| EventPushFiltered | |
| EventPushFailure Text |
Instances
emptyRegisteredEvent :: RegisteredEventData #
A registered event with no associated data.
This is a resonable baseline to modify for converting to
RegisteredEventData.
registerEvent :: MonadIO m => (RegisteredEventData -> Timestamp -> IO (Maybe a)) -> (a -> IO RegisteredEventData) -> m (Maybe (RegisteredEventType a)) #
Register a new event type with SDL.
Provide functions that convert between UserEventData and your structure.
You can then use pushRegisteredEvent to add a custom event of the
registered type to the queue, and getRegisteredEvent to test for such
events in the main loop.
Watching events
type EventWatchCallback = Event -> IO () #
An EventWatchCallback can process and respond to an event
when it is added to the event queue.
data EventWatch #
addEventWatch :: MonadIO m => EventWatchCallback -> m EventWatch #
Trigger an EventWatchCallback when an event is added to the SDL
event queue.
See https://wiki.libsdl.org/SDL_AddEventWatch for C documentation.
delEventWatch :: MonadIO m => EventWatch -> m () #
Remove an EventWatch.
See https://wiki.libsdl.org/SDL_DelEventWatch for C documentation.
Event data
A single SDL event. This event occured at eventTimestamp and carries data under eventPayload.
Constructors
| Event | |
Fields
| |
Instances
| Eq Event # | |
| Ord Event # | |
| Show Event # | |
| Generic Event # | |
| type Rep Event # | |
Defined in SDL.Event type Rep Event = D1 (MetaData "Event" "SDL.Event" "sdl2-2.4.1.0-BSoUqVHl3myLrLd0xltRmd" False) (C1 (MetaCons "Event" PrefixI True) (S1 (MetaSel (Just "eventTimestamp") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Timestamp) :*: S1 (MetaSel (Just "eventPayload") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 EventPayload))) | |
data EventPayload #
An enumeration of all possible SDL event types. This data type pairs up event types with their payload, where possible.
Constructors
Instances
Window events
newtype WindowShownEventData #
A window has been shown.
Constructors
| WindowShownEventData | |
Fields
| |
Instances
newtype WindowHiddenEventData #
A window has been hidden.
Constructors
| WindowHiddenEventData | |
Fields
| |
Instances
newtype WindowExposedEventData #
A part of a window has been exposed - where exposure means to become visible (for example, an overlapping window no longer overlaps with the window).
Constructors
| WindowExposedEventData | |
Fields
| |
Instances
data WindowMovedEventData #
A Window has been moved.
Constructors
| WindowMovedEventData | |
Fields
| |
Instances
data WindowResizedEventData #
Window has been resized. This is event is always preceded by WindowSizeChangedEvent.
Constructors
| WindowResizedEventData | |
Fields
| |
Instances
data WindowSizeChangedEventData #
The window size has changed, either as a result of an API call or through the system or user changing the window size; this event is followed by WindowResizedEvent if the size was changed by an external event, i.e. the user or the window manager.
Constructors
| WindowSizeChangedEventData | |
Fields
| |
Instances
newtype WindowMinimizedEventData #
The window has been minimized.
Constructors
| WindowMinimizedEventData | |
Fields
| |
Instances
newtype WindowMaximizedEventData #
The window has been maximized.
Constructors
| WindowMaximizedEventData | |
Fields
| |
Instances
newtype WindowRestoredEventData #
The window has been restored to normal size and position.
Constructors
| WindowRestoredEventData | |
Fields
| |
Instances
newtype WindowGainedMouseFocusEventData #
The window has gained mouse focus.
Constructors
| WindowGainedMouseFocusEventData | |
Fields
| |
Instances
newtype WindowLostMouseFocusEventData #
The window has lost mouse focus.
Constructors
| WindowLostMouseFocusEventData | |
Fields
| |
Instances
newtype WindowGainedKeyboardFocusEventData #
The window has gained keyboard focus.
Constructors
| WindowGainedKeyboardFocusEventData | |
Fields
| |
Instances
newtype WindowLostKeyboardFocusEventData #
The window has lost keyboard focus.
Constructors
| WindowLostKeyboardFocusEventData | |
Fields
| |
Instances
newtype WindowClosedEventData #
The window manager requests that the window be closed.
Constructors
| WindowClosedEventData | |
Fields
| |
Instances
newtype SysWMEventData #
A video driver dependent system event
Constructors
| SysWMEventData | |
Fields | |
Instances
Keyboard events
data KeyboardEventData #
A keyboard key has been pressed or released.
Constructors
| KeyboardEventData | |
Fields
| |
Instances
data TextEditingEventData #
Keyboard text editing event information.
Constructors
| TextEditingEventData | |
Fields
| |
Instances
data TextInputEventData #
Keyboard text input event information.
Constructors
| TextInputEventData | |
Fields
| |
Instances
Mouse events
data MouseMotionEventData #
A mouse or pointer device was moved.
Constructors
| MouseMotionEventData | |
Fields
| |
Instances
data MouseButtonEventData #
A mouse or pointer device button was pressed or released.
Constructors
| MouseButtonEventData | |
Fields
| |
Instances
data MouseWheelEventData #
Mouse wheel event information.
Constructors
| MouseWheelEventData | |
Fields
| |
Instances
Joystick events
data JoyAxisEventData #
Joystick axis motion event information
Constructors
| JoyAxisEventData | |
Fields
| |
Instances
data JoyBallEventData #
Joystick trackball motion event information.
Constructors
| JoyBallEventData | |
Fields
| |
Instances
data JoyHatEventData #
Joystick hat position change event information
Constructors
| JoyHatEventData | |
Fields
| |
Instances
data JoyButtonEventData #
Joystick button event information.
Constructors
| JoyButtonEventData | |
Fields
| |
Instances
data JoyDeviceEventData #
Joystick device event information.
Constructors
| JoyDeviceEventData | |
Fields
| |
Instances
Controller events
data ControllerAxisEventData #
Game controller axis motion event information.
Constructors
| ControllerAxisEventData | |
Fields
| |
Instances
data ControllerButtonEventData #
Game controller button event information
Constructors
| ControllerButtonEventData | |
Fields
| |
Instances
data ControllerDeviceEventData #
Controller device event information
Constructors
| ControllerDeviceEventData | |
Fields
| |
Instances
Audio events
data AudioDeviceEventData #
Constructors
| AudioDeviceEventData | |
Fields
| |
Instances
User events
data UserEventData #
Event data for application-defined events.
Constructors
| UserEventData | |
Fields
| |
Instances
Touch events
data TouchFingerEventData #
Finger touch event information.
Constructors
| TouchFingerEventData | |
Fields
| |
Instances
data TouchFingerMotionEventData #
Finger motion event information.
Constructors
| TouchFingerMotionEventData | |
Fields
| |
Instances
Gesture events
data MultiGestureEventData #
Multiple finger gesture event information
Constructors
| MultiGestureEventData | |
Fields
| |
Instances
data DollarGestureEventData #
Complex gesture event information.
Constructors
| DollarGestureEventData | |
Fields
| |
Instances
Drag and drop events
newtype DropEventData #
An event used to request a file open by the system
Constructors
| DropEventData | |
Fields
| |
Instances
Unknown events
newtype UnknownEventData #
SDL reported an unknown event type.
Constructors
| UnknownEventData | |
Fields
| |
Instances
Auxiliary event data
data InputMotion #
Instances
data MouseButton #
Constructors
| ButtonLeft | |
| ButtonMiddle | |
| ButtonRight | |
| ButtonX1 | |
| ButtonX2 | |
| ButtonExtra !Int | An unknown mouse button. |