gi-gdk4-4.0.10: Gdk bindings
CopyrightWill Thompson and Iñaki García Etxebarria
LicenseLGPL-2.1
MaintainerIñaki García Etxebarria
Safe HaskellNone
LanguageHaskell2010

GI.Gdk.Objects.Cursor

Description

Used to create and destroy cursors.

Cursors are immutable objects, so once you created them, there is no way to modify them later. You should create a new cursor when you want to change something about it.

Cursors by themselves are not very interesting: they must be bound to a window for users to see them. This is done with surfaceSetCursor or surfaceSetDeviceCursor. Applications will typically use higher-level GTK functions such as gtk_widget_set_cursor() instead.

Cursors are not bound to a given Display, so they can be shared. However, the appearance of cursors may vary when used on different platforms.

Named and texture cursors

There are multiple ways to create cursors. The platform's own cursors can be created with cursorNewFromName. That function lists the commonly available names that are shared with the CSS specification. Other names may be available, depending on the platform in use. On some platforms, what images are used for named cursors may be influenced by the cursor theme.

Another option to create a cursor is to use cursorNewFromTexture and provide an image to use for the cursor.

To ease work with unsupported cursors, a fallback cursor can be provided. If a Surface cannot use a cursor because of the reasons mentioned above, it will try the fallback cursor. Fallback cursors can themselves have fallback cursors again, so it is possible to provide a chain of progressively easier to support cursors. If none of the provided cursors can be supported, the default cursor will be the ultimate fallback.

Synopsis

Exported types

newtype Cursor Source #

Memory-managed wrapper type.

Constructors

Cursor (ManagedPtr Cursor) 

Instances

Instances details
Eq Cursor Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

Methods

(==) :: Cursor -> Cursor -> Bool

(/=) :: Cursor -> Cursor -> Bool

GObject Cursor Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

ManagedPtrNewtype Cursor Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

TypedObject Cursor Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

Methods

glibType :: IO GType #

HasParentTypes Cursor Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

IsGValue (Maybe Cursor) Source #

Convert Cursor to and from GValue. See toGValue and fromGValue.

Instance details

Defined in GI.Gdk.Objects.Cursor

Methods

gvalueGType_ :: IO GType #

gvalueSet_ :: Ptr GValue -> Maybe Cursor -> IO () #

gvalueGet_ :: Ptr GValue -> IO (Maybe Cursor) #

type ParentTypes Cursor Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

type ParentTypes Cursor = '[Object]

class (GObject o, IsDescendantOf Cursor o) => IsCursor o Source #

Type class for types which can be safely cast to Cursor, for instance with toCursor.

Instances

Instances details
(GObject o, IsDescendantOf Cursor o) => IsCursor o Source # 
Instance details

Defined in GI.Gdk.Objects.Cursor

toCursor :: (MonadIO m, IsCursor o) => o -> m Cursor Source #

Cast to Cursor, for types for which this is known to be safe. For general casts, use castTo.

Methods

getFallback

cursorGetFallback Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> a

cursor: a GdkCursor

-> m (Maybe Cursor)

Returns: the fallback of the cursor or Nothing to use the default cursor as fallback

Returns the fallback for this cursor.

The fallback will be used if this cursor is not available on a given GdkDisplay. For named cursors, this can happen when using nonstandard names or when using an incomplete cursor theme. For textured cursors, this can happen when the texture is too large or when the GdkDisplay it is used on does not support textured cursors.

getHotspotX

cursorGetHotspotX Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> a

cursor: a GdkCursor

-> m Int32

Returns: the horizontal offset of the hotspot or 0 for named cursors

Returns the horizontal offset of the hotspot.

The hotspot indicates the pixel that will be directly above the cursor.

Note that named cursors may have a nonzero hotspot, but this function will only return the hotspot position for cursors created with cursorNewFromTexture.

getHotspotY

cursorGetHotspotY Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> a

cursor: a GdkCursor

-> m Int32

Returns: the vertical offset of the hotspot or 0 for named cursors

Returns the vertical offset of the hotspot.

The hotspot indicates the pixel that will be directly above the cursor.

Note that named cursors may have a nonzero hotspot, but this function will only return the hotspot position for cursors created with cursorNewFromTexture.

getName

cursorGetName Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> a

cursor: a GdkCursor

-> m (Maybe Text)

Returns: the name of the cursor or Nothing if it is not a named cursor

Returns the name of the cursor.

If the cursor is not a named cursor, Nothing will be returned.

getTexture

cursorGetTexture Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> a

cursor: a GdkCursor

-> m (Maybe Texture)

Returns: the texture for cursor or Nothing if it is a named cursor

Returns the texture for the cursor.

If the cursor is a named cursor, Nothing will be returned.

newFromCallback

cursorNewFromCallback Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> CursorGetTextureCallback

callback: the GdkCursorGetTextureCallback

-> Maybe a

fallback: the GdkCursor to fall back to when this one cannot be supported

-> m (Maybe Cursor)

Returns: a new GdkCursor

Creates a new callback-based cursor object.

Cursors of this kind produce textures for the cursor image on demand, when the callback is called.

Since: 4.16

newFromName

cursorNewFromName Source #

Arguments

:: (HasCallStack, MonadIO m, IsCursor a) 
=> Text

name: the name of the cursor

-> Maybe a

fallback: Nothing or the GdkCursor to fall back to when this one cannot be supported

-> m (Maybe Cursor)

Returns: a new GdkCursor, or Nothing if there is no cursor with the given name

Creates a new cursor by looking up name in the current cursor theme.

A recommended set of cursor names that will work across different platforms can be found in the CSS specification:

| | | | | --- | --- | --- | | | "none" | No cursor | | | "default" | The default cursor | | | "help" | Help is available | | | "pointer" | Indicates a link or interactive element | | |"context-menu" | A context menu is available | | | "progress" | Progress indicator | | | "wait" | Busy cursor | | | "cell" | Cell(s) may be selected | | | "crosshair" | Simple crosshair | | | "text" | Text may be selected | | | "vertical-text" | Vertical text may be selected | | | "alias" | DND: Something will be linked | | | "copy" | DND: Something will be copied | | | "move" | DND: Something will be moved | | | "dnd-ask" | DND: User can choose action to be carried out | | | "no-drop" | DND: Can't drop here | | | "not-allowed" | DND: Action will not be carried out | | | "grab" | DND: Something can be grabbed | | | "grabbing" | DND: Something is being grabbed | | | "n-resize" | Resizing: Move north border | | | "e-resize" | Resizing: Move east border | | | "s-resize" | Resizing: Move south border | | | "w-resize" | Resizing: Move west border | | | "ne-resize" | Resizing: Move north-east corner | | | "nw-resize" | Resizing: Move north-west corner | | | "sw-resize" | Resizing: Move south-west corner | | | "se-resize" | Resizing: Move south-east corner | | | "col-resize" | Resizing: Move an item or border horizontally | | | "row-resize" | Resizing: Move an item or border vertically | | | "ew-resize" | Moving: Something can be moved horizontally | | | "ns-resize" | Moving: Something can be moved vertically | | | "nesw-resize" | Moving: Something can be moved diagonally, north-east to south-west | | | "nwse-resize" | Moving: something can be moved diagonally, north-west to south-east | | | "all-resize" | Moving: Something can be moved in any direction | | | "all-scroll" | Can scroll in any direction | | | "zoom-in" | Zoom in | | | "zoom-out" | Zoom out |

newFromTexture

cursorNewFromTexture Source #

Arguments

:: (HasCallStack, MonadIO m, IsTexture a, IsCursor b) 
=> a

texture: the texture providing the pixel data

-> Int32

hotspotX: the horizontal offset of the “hotspot” of the cursor

-> Int32

hotspotY: the vertical offset of the “hotspot” of the cursor

-> Maybe b

fallback: the GdkCursor to fall back to when this one cannot be supported

-> m Cursor

Returns: a new GdkCursor

Creates a new cursor from a GdkTexture.

Properties

fallback

Cursor to fall back to if this cursor cannot be displayed.

constructCursorFallback :: (IsCursor o, MonadIO m, IsCursor a) => a -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “fallback” property. This is rarely needed directly, but it is used by new.

getCursorFallback :: (MonadIO m, IsCursor o) => o -> m (Maybe Cursor) Source #

Get the value of the “fallback” property. When overloading is enabled, this is equivalent to

get cursor #fallback

hotspotX

X position of the cursor hotspot in the cursor image.

constructCursorHotspotX :: (IsCursor o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “hotspot-x” property. This is rarely needed directly, but it is used by new.

getCursorHotspotX :: (MonadIO m, IsCursor o) => o -> m Int32 Source #

Get the value of the “hotspot-x” property. When overloading is enabled, this is equivalent to

get cursor #hotspotX

hotspotY

Y position of the cursor hotspot in the cursor image.

constructCursorHotspotY :: (IsCursor o, MonadIO m) => Int32 -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “hotspot-y” property. This is rarely needed directly, but it is used by new.

getCursorHotspotY :: (MonadIO m, IsCursor o) => o -> m Int32 Source #

Get the value of the “hotspot-y” property. When overloading is enabled, this is equivalent to

get cursor #hotspotY

name

Name of this this cursor.

The name will be Nothing if the cursor was created from a texture.

constructCursorName :: (IsCursor o, MonadIO m) => Text -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “name” property. This is rarely needed directly, but it is used by new.

getCursorName :: (MonadIO m, IsCursor o) => o -> m (Maybe Text) Source #

Get the value of the “name” property. When overloading is enabled, this is equivalent to

get cursor #name

texture

The texture displayed by this cursor.

The texture will be Nothing if the cursor was created from a name.

constructCursorTexture :: (IsCursor o, MonadIO m, IsTexture a) => a -> m (GValueConstruct o) Source #

Construct a GValueConstruct with valid value for the “texture” property. This is rarely needed directly, but it is used by new.

getCursorTexture :: (MonadIO m, IsCursor o) => o -> m (Maybe Texture) Source #

Get the value of the “texture” property. When overloading is enabled, this is equivalent to

get cursor #texture