constructor (new tree-widget%        [ [wheel-step wheel-step]]         ...superclass-args...)

→ (is-a?/c tree-widget%)

wheel-step : exact-positive-integer? = 3

The wheel-step argument controls the speed of scrolling.

method (send a-tree-widget get-root) → root-cursor?

Returns a cursor representing the root of the tree.

method (send a-tree-widget set-root c) → void?

c : root-cursor?

Set the root of the tree.

method (send a-tree-widget append-item c v [expand?]) → void?

c : generic-cursor?

v : any/c

expand? : boolean? = #f

Appends an item v to the children of c. All the cursors acquired previously will be invalidated.

method (send a-tree-widget prepend-item   c             v            [ expand?])   →   void?

c : generic-cursor?

v : any/c

expand? : boolean? = #f

Prepends an item v to the children of c. All the cursors acquired previously will be invalidated.

method (send a-tree-widget insert-item   c             i             v            [ expand?])   →   void?

c : generic-cursor?

i : exact-nonnegative-integer?

v : any/c

expand? : boolean? = #f

Inserts an item v as the ith child of c. All the cursors acquired previously will be invalidated.

method (send a-tree-widget update-item c i v) → void?

c : generic-cursor?

i : exact-nonnegative-integer?

v : any/c

Updates the ith child of c to v. All the cursors acquired previously will be invalidated.

method (send a-tree-widget delete-item c i) → void?

c : generic-cursor?

i : exact-nonnegative-integer?

Deletes the ith child of c. All the cursors acquired previously will be invalidated.

method (send a-tree-widget expand-item c expand?) → void?

c : generic-cursor?

expand? : boolean?

Changes the expanding status of c to expand?. All the cursors acquired previously will be invalidated.

method (send a-tree-widget reset-items) → void

Resets the tree to empty. All the cursors acquired previously will be invalidated.

method (send a-tree-widget on-positions-changed) → void?

Called after the tree is modified.

Default Implementation: Calls refresh.

method (send a-tree-widget paint-item c v x y) → void?

c : node-cursor?

v : any/c

x : exact-nonnegative-integer?

y : exact-nonnegative-integer?

Paints the item v represented by cursor c at specific dc location.

method (send a-tree-widget compute-item-size v)

→   exact-positive-integer? exact-positive-integer? exact-nonnegative-integer?

v : any/c

Overrides compute-item-size in tree<%>.

Computes the width, height and children indentation of item v.

Default Implementation: Returns (values 1 1 0).

method (send a-tree-widget locate-item x y) → (or/c #f node-cursor?)

x : (or/c #f exact-nonnegative-integer?)

y : exact-nonnegative-integer?

Finds out the item at specific location (dc coordinates). If x is #f, only y is considered.

method (send a-tree-widget make-indices-cursor indices)

→ indices-cursor?

indices : (non-empty-listof exact-nonnegative-integer?)

Constructs an cursor from indices, which should be only used to modify the tree immediately. Equivalent to

(for/fold ([t (send this get-root)])

([i (in-list indices)])

(cursor-get-child t i))

when used to modify the tree.

method (send a-tree get-root) → root-cursor?

Returns a cursor representing the root of the tree.

method (send a-tree set-root c) → void?

c : root-cursor?

Set the root of the tree.

method (send a-tree compute-item-size v)   →   exact-positive-integer? exact-positive-integer? exact-nonnegative-integer?

v : any/c

Computes the width, height and children indentation of item v.

method (send a-tree on-positions-changed) → void?

Called after the tree is modified.

constructor (new tree-updater% [tree tree]) → (is-a?/c tree-updater%)

tree : (instanceof/c (implementation?/c tree<%>))

Constructs a tree-updater% associated with tree.

method (send a-tree-updater append-item   t             v            [ expand?             children])   →   root-cursor?

t : generic-cursor?

v : any/c

expand? : boolean? = #f

children : (or/c #f cursor?) = #f

method (send a-tree-updater prepend-item   t             v            [ expand?             children])   →   root-cursor?

t : generic-cursor?

v : any/c

expand? : boolean? = #f

children : (or/c #f cursor?) = #f

method (send a-tree-updater insert-item   t             i             v            [ expand?             children])   →   root-cursor?

t : generic-cursor?

i : exact-nonnegative-integer?

v : any/c

expand? : boolean? = #f

children : (or/c #f cursor?) = #f

method (send a-tree-updater update-item t i v) → root-cursor?

t : generic-cursor?

i : exact-nonnegative-integer?

v : any/c

method (send a-tree-updater delete-item t i) → root-cursor?

t : generic-cursor?

i : exact-nonnegative-integer?

method (send a-tree-updater expand-item t expand?) → root-cursor?

t : generic-cursor?

expand? : boolean?

method (send a-tree-updater update-children t f) → root-cursor?

t : generic-cursor?

f : (-> root-cursor? root-cursor?)

method (send a-tree-updater set-tree tree) → void?

tree : root-cursor?

Set the root of associated tree<%> to tree.

method (send a-tree-updater empty-tree) → root-cursor?

procedure (root-cursor? v) → boolean?

v : any/c

procedure (node-cursor? v) → boolean?

v : any/c

procedure (cursor? v) → boolean?

v : any/c

procedure (indices-cursor? v) → boolean?

v : any/c

procedure (generic-cursor? v) → boolean?

v : any/c

procedure (cursor-up c) → cursor?

c : cursor?

procedure (cursor-equal? a b) → boolean?

a : cursor?

b : cursor?

procedure (cursor-valid? t c) → boolean?

t : root-cursor?

c : cursor?

procedure (cursor-children c) → (listof node-cursor?)

c : cursor?

procedure (cursor-children-cursor c) → root-cursor?

c : cursor?

procedure (cursor-children-count c) → exact-nonnegative-integer?

c : cursor?

procedure (cursor-get-child c i) → node-cursor?

c : cursor?

i : exact-nonnegative-integer?

procedure (node-cursor-item-size c)   →   exact-positive-integer? exact-positive-integer?

c : node-cursor?

procedure (node-cursor-value c) → any/c

c : node-cursor?

procedure (node-cursor-expand? c) → boolean?

c : node-cursor?

procedure (node-cursor-pos c) → exact-nonnegative-integer?

c : node-cursor?

procedure (node-cursor-children-indent c) → exact-nonnegative-integer?

c : node-cursor?

procedure (root-cursor-total-size c)   →   exact-nonnegative-integer? exact-nonnegative-integer?

c : root-cursor?

procedure (root-cursor-locate-item c x y) → (or/c #f node-cursor?)

c : root-cursor?

x : (or/c #f exact-nonnegative-integer?)

y : exact-nonnegative-integer?

procedure (root-cursor-get-visible-items   c       y-start       y-end)

→ (listof (vector/c node-cursor? exact-nonnegative-integer? any/c))

c : root-cursor?

y-start : exact-nonnegative-integer?

y-end : exact-nonnegative-integer?