HTk.Canvasitems.CanvasTag

Documentation

data CanvasTag

The CanvasTag datatype.

Instances

Eq CanvasTag

Methods

(==) :: CanvasTag -> CanvasTag -> Bool

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

Destroyable CanvasTag

A canvas tag can be destroyed.

Methods

destroy :: CanvasTag -> IO ()

Synchronized CanvasTag

You can synchronize on a canvas tag.

Methods

synchronize :: CanvasTag -> IO b -> IO b

GUIObject CanvasTag

Internal.

Methods

toGUIObject :: CanvasTag -> GUIOBJECT

cname :: CanvasTag -> String

cset :: GUIValue a => CanvasTag -> ConfigID -> a -> IO CanvasTag

cget :: GUIValue a => CanvasTag -> ConfigID -> IO a

CanvasItem CanvasTag

A canvas tag is a canvas item (any canvas item is an instance of the abstract class CanvasItem).

class CanvasItem w => TaggedCanvasItem w where

A canvas item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config w

Instances

TaggedCanvasItem EmbeddedCanvasWin

An embedded canvas window can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config EmbeddedCanvasWin

TaggedCanvasItem ImageItem

A image item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config ImageItem

TaggedCanvasItem Line

A line item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config Line

TaggedCanvasItem Oval

An oval item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config Oval

TaggedCanvasItem Polygon

A polygon item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config Polygon

TaggedCanvasItem Rectangle

A rectangle item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config Rectangle

TaggedCanvasItem TextItem

A text item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config TextItem

TaggedCanvasItem BitMapItem

A bitmap item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config BitMapItem

TaggedCanvasItem Arc

An arc item can have several tags (handlers for a set of canvas items).

Methods

tags :: [CanvasTag] -> Config Arc

data SearchSpec

The SearchSpec datatype (see addCanvasTag).

allItems

Arguments

:: SearchSpec

A SearchSpec object.

Adds all objects in the canvas.

aboveItem

Arguments

:: CanvasItem item

=> item

the item below the item to add.

-> SearchSpec

A SearchSpec object.

Adds the item just above the given item in the display list.

belowItem

Arguments

:: CanvasItem item

=> item

the item above the item to add.

-> SearchSpec

A SearchSpec object.

Adds the item just below in the given item in the display list.

withTag

Arguments

:: CanvasItem item

=> item

the canvas item handler.

-> SearchSpec

A SearchSpec object.

Adds the item(s) identified by the given handler (which can also be another canvas tag).

closest

Arguments

:: Position

the concerned position.

-> SearchSpec

A SearchSpec object.

Adds the item closest to the given position.

enclosed

Arguments

:: Position

the upper left position of the region.

-> Position

the lower right position of the region.

-> SearchSpec

A SearchSpec object.

Adds the items enclosed in the specified region.

overlapping

Arguments

:: Position

the upper left position of the region.

-> Position

the lower right position of the region.

-> SearchSpec

A SearchSpec object.

Adds the items overpalling the specified region.

createCanvasTag

Arguments

:: Canvas

the parent canvas.

-> [Config CanvasTag]

the list of configuration options for this canvas tag.

-> IO CanvasTag

A canvas tag.

Constructs a new canvas tag.

addCanvasTag

Arguments

:: SearchSpec

the search specification.

-> CanvasTag

the tag to add items to.

-> IO ()

None.

Adds the canvas items identified by the SearchSpec to the tag.

removeCanvasTag

Arguments

:: CanvasItem i

=> i

the item to remove from the tag.

-> CanvasTag

the tag to remove the item from.

-> IO ()

None.

Removes a canvas item from a canvas tag.

(&#&) infixr 3

Arguments

:: CanvasTag

-> CanvasTag

-> IO CanvasTag

new canvas tag corresponding to (t1&&t2)

Forms the conjunction of two canvas tags

(|#|) infixr 2

Arguments

:: CanvasTag

-> CanvasTag

-> IO CanvasTag

new canvas tag corresponding to (t1||t2)

Forms the disjunction of two canvas tags

(^#) infixr 2

Arguments

:: CanvasTag

-> CanvasTag

-> IO CanvasTag

new canvas tag corresponding to (t1^t2) equals (!t1&&t2)||(t1&&!t2)

Forms "either - or" of two canvas tags

tagNot

Arguments

:: CanvasTag

-> IO CanvasTag

new canvas tag corresponding to !t