org.jscroll.widgets
Class FramePositioning

java.lang.Object
  |
  +--org.jscroll.widgets.FramePositioning

All Implemented Interfaces:

DesktopConstants

public class FramePositioning

extends Object

implements DesktopConstants

This class provides internal frame positioning methods for use by DesktopScrollPane.

Version:

1.0 11-Aug-2001

Author:

Tom Tessier

Field Summary

Fields inherited from interface org.jscroll.widgets.DesktopConstants

CONTENTS_CHANGED_COLOR, MAX_FRAMES, MAXIMUM_BUTTON_WIDTH, MINIMUM_BUTTON_WIDTH, X_OFFSET, Y_OFFSET

Constructor Summary

FramePositioning(DesktopScrollPane desktopScrollpane)
creates the FramePositioning object

Method Summary

Point	cascadeInternalFrame(JInternalFrame f) cascades the given internal frame based upon the current number of internal frames
void	cascadeInternalFrames() cycles through and cascades all internal frames
boolean	getAutoTile() returns the autoTile mode
void	setAutoTile(boolean autoTile) turns autoTile on or off
void	tileInternalFrames() tiles internal frames upon the desktop.

Methods inherited from class java.lang.Object

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

Constructor Detail

FramePositioning

public FramePositioning(DesktopScrollPane desktopScrollpane)

creates the FramePositioning object

Parameters:

desktopScrollpane - a reference to the DesktopScrollpane object

Method Detail

setAutoTile

public void setAutoTile(boolean autoTile)

turns autoTile on or off

Parameters:

autoTile - boolean representing autoTile mode. If true, then all new frames are tiled automatically. If false, then all new frames are cascaded automatically.

getAutoTile

public boolean getAutoTile()

returns the autoTile mode

Returns:

boolean representing current autoTile mode

cascadeInternalFrames

public void cascadeInternalFrames()

cycles through and cascades all internal frames

cascadeInternalFrame

public Point cascadeInternalFrame(JInternalFrame f)

cascades the given internal frame based upon the current number of internal frames

Parameters:

f - the internal frame to cascade

Returns:

a Point object representing the location assigned to the internal frame upon the virtual desktop

tileInternalFrames

public void tileInternalFrames()

tiles internal frames upon the desktop.

Based upon the following tiling algorithm:

- take the sqroot of the total frames rounded down, that gives the number of columns.

- divide the total frames by the # of columns to get the # of rows in each column, and any remainder is distributed amongst the remaining rows from right to left)

eg)
1 frame, remainder 0, 1 row
2 frames, remainder 0, 2 rows
3 frames, remainder 0, 3 rows
4 frames, remainder 0, 2 rows x 2 columns
5 frames, remainder 1, 2 rows in column I, 3 rows in column II
10 frames, remainder 1, 3 rows in column I, 3 rows in column II, 4 rows in column III
16 frames, 4 rows x 4 columns


Pseudocode:

while (frames) {
numCols = (int)sqrt(totalFrames);
numRows = totalFrames / numCols;
remainder = totalFrames % numCols
if ((numCols-curCol) <= remainder) {
numRows++; // add an extra row for this column
}
}