brf.j2me.dynaworks.ui
Class Tree

java.lang.Object
  |
  +--brf.j2me.dynaworks.ui.BasicWidget
        |
        +--brf.j2me.dynaworks.ui.Tree

All Implemented Interfaces:

UserWidget

public class Tree

extends BasicWidget

Provides a class that does hierarchical layout of information.

It implements a Windows Explorer-like hiearchical tree type view of a Vector of TreeItems. When an item-specific event happens (ie. a double-click on an icon or label) an Event is generated, whose argument is the TreeItem affected.

Version:

1.0

Author:

Bernd R. Fix

See Also:

BasicWidget, UserWidget

Field Summary

static int	COLLAPSE Event sent when a drawer is closed.
private TreeItem	currItem reference to currently active item.
protected java.util.Vector	displayedList Items able to be displayed
protected int	displayNum Default value for how many items we can display.
private int	dragState current dragging mode
private int	dragX we are dragging from here (x-coordinate).
private int	dragY we are dragging from here (y-coordinate).
static int	EXPAND Event sent when a drawer is opened.
private int	firstVisible index of first visible tree item.
private int	height height of a tree control.
private ScrollBar	hs horizontal scrollbar.
private static Bitmap	minusSign Bitmap "-"
private static Bitmap	plusSign Bitmap "+"
protected java.util.Vector	rootItems The items in this Tree.
private int	scrollX horizontal scroll position.
private int	scrollXmax maximum x-scroll value for current layout.
private int	scrollY vertical scroll position.
private int	scrollYmax maximum y-scroll value for current layout.
static int	SIMPLE Style mode flags.
private int	syncState status of synchronization: 0 = up-to-date
private ScrollBar	vs vertical scrollbar.
private int	width width of the tree canvas.

Fields inherited from class brf.j2me.dynaworks.ui.BasicWidget

g, h, w, x, y

Constructor Summary

Tree(int x, int y, int w, int h, int style)
Creates an empty Tree.

Method Summary

(package private) static void	()
void	addRoot(TreeItem item) Inserts the item as a root item in the tree.
private int	addToDisplayedList(TreeItem item, int level) add an item to the list of displayed list.
void	collapse(TreeItem item) Collapses a branch.
void	expand(TreeItem item) Makes the subtree visible
private boolean	expandIconClick(TreeItem item) branch is expanding (true) or collapsing (false).
TreeItem	getSelectedItem() Return the selected item in the tree, null if the tree is empty.
ActionEvent	handlePenDown(int xc, int yc) Handle a "pen down" event.
ActionEvent	handlePenMove(int xc, int yc) Handle a "pen move" event.
ActionEvent	handlePenUp(int xc, int yc) Handle a "pen up" event.
private void	initStyle(int style) setup the style.
void	paint() paint the graphics area.
void	removeAll() deletes all items in the tree.
boolean	removeRoot(TreeItem item) Deletes the item from the list of root items.
void	selectItem(TreeItem item) selects the item
protected void	setHorizontalOffset(int offset) Sets the horizontal offset for painting the tree anf can be used e.g.
protected void	setVerticalOffset(int offset) Sets the vertical offset for painting the tree anf can be used e.g.
private void	sync() synchronize inner state (list of displayed tree items.

Methods inherited from class brf.j2me.dynaworks.ui.BasicWidget

contains, handleKeyDown, handleSysKeyDown, hasFocus, loseFocus, setFocus

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, registerNatives, toString, wait, wait, wait

Field Detail

SIMPLE

public static final int SIMPLE

Style mode flags.

EXPAND

public static final int EXPAND

Event sent when a drawer is opened.

COLLAPSE

public static final int COLLAPSE

Event sent when a drawer is closed.

width

private int width

width of the tree canvas.

height

private int height

height of a tree control.

hs

private ScrollBar hs

horizontal scrollbar.

scrollX

private int scrollX

horizontal scroll position.

scrollXmax

private int scrollXmax

maximum x-scroll value for current layout.

vs

private ScrollBar vs

vertical scrollbar.

scrollY

private int scrollY

vertical scroll position.

scrollYmax

private int scrollYmax

maximum y-scroll value for current layout.

dragState

private int dragState

current dragging mode

dragX

private int dragX

we are dragging from here (x-coordinate).

dragY

private int dragY

we are dragging from here (y-coordinate).

rootItems

protected java.util.Vector rootItems

The items in this Tree.

currItem

private TreeItem currItem

reference to currently active item.

firstVisible

private int firstVisible

index of first visible tree item.

displayedList

protected java.util.Vector displayedList

Items able to be displayed

displayNum

protected int displayNum

Default value for how many items we can display. Will be adjusted according to the window size.

syncState

private int syncState

status of synchronization: 0 = up-to-date

plusSign

private static Bitmap plusSign

Bitmap "+"

minusSign

private static Bitmap minusSign

Bitmap "-"

Constructor Detail

Tree

public Tree(int x,
            int y,
            int w,
            int h,
            int style)

Creates an empty Tree.

Parameters:

x - int - x-ccordinate of upper-left corner.

y - int - y-coordinate of upper left corner.

w - int - width of control.

h - int - height of control.

Method Detail

static void ()

paint

public void paint()

paint the graphics area.

Overrides:

paint in class BasicWidget

initStyle

private void initStyle(int style)

setup the style.

Parameters:

style - int - tree style to be used.

getSelectedItem

public TreeItem getSelectedItem()

Return the selected item in the tree, null if the tree is empty.

Returns:

TreeItem - reference to selected item or null

setHorizontalOffset

protected void setHorizontalOffset(int offset)

Sets the horizontal offset for painting the tree anf can be used e.g. for a scrollbar.

Parameters:

offset - int - use value as new horizontal offset.

setVerticalOffset

protected void setVerticalOffset(int offset)

Sets the vertical offset for painting the tree anf can be used e.g. for a scrollbar.

Parameters:

offset - int - use value as new vertical offset.

addRoot

public void addRoot(TreeItem item)

Inserts the item as a root item in the tree.

Parameters:

item - TreeItem - item to be inserted.

removeRoot

public boolean removeRoot(TreeItem item)

Deletes the item from the list of root items.

Parameters:

item - TreeItem - item to be removed

Returns:

true if the argument was part of the tree; false otherwise

removeAll

public void removeAll()

deletes all items in the tree.

expand

public void expand(TreeItem item)

Makes the subtree visible

Parameters:

item - TreeItem - item to be expanded

collapse

public void collapse(TreeItem item)

Collapses a branch.

Parameters:

item - TreeItem - branch to collapse.

selectItem

public void selectItem(TreeItem item)

selects the item

Parameters:

item - TreeItem - item to be selected

addToDisplayedList

private int addToDisplayedList(TreeItem item,
                               int level)

add an item to the list of displayed list. If the item is a parent, it's children are added to the list recursively.

Parameters:

item - TreeItem - item to be added

Returns:

int - number of lines added to the list.

sync

private void sync()

synchronize inner state (list of displayed tree items.

expandIconClick

private boolean expandIconClick(TreeItem item)

branch is expanding (true) or collapsing (false).

Parameters:

item - TreeItem - toggle collapse/expand for this item.

handlePenDown

public ActionEvent handlePenDown(int xc,
                                 int yc)

Handle a "pen down" event.

Overrides:

handlePenDown in class BasicWidget

Parameters:

xc - int - x coordinate of point

yc - int - y coordinate of point

Returns:

ActionEvent - ActionEvent code (or null)

handlePenMove

public ActionEvent handlePenMove(int xc,
                                 int yc)

Handle a "pen move" event.

Overrides:

handlePenMove in class BasicWidget

Parameters:

xc - int - x coordinate of current point

yc - int - y coordinate of current point

Returns:

ActionEvent - ActionEvent code (or null)

handlePenUp

public ActionEvent handlePenUp(int xc,
                               int yc)

Handle a "pen up" event.

Overrides:

handlePenUp in class BasicWidget

Parameters:

xc - int - x coordinate of current point

yc - int - y coordinate of current point

Returns:

ActionEvent - ActionEvent code (or null)