package jas.util.layout;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.LayoutManager;
import javax.swing.JToolBar;
/**
* A ToolbarLayout arranges components in a left-to-right flow, much
* like the FlowLayout which is supplied with the JDK. However, it
* fixes the problem with the FlowLayout that occurs when a FlowLayout
* is for a North aligned component of a BorderLayout--namely, that
* if the window is shrunk so that some of the components within the
* FlowLayout wrap to the next line the component does not grow in
* height to support this wrapping. This bug was caused by the library
* designers using the preferred size in recalculating, not the size
* which is determined by the window width. As such, the flow layout
* would always want to be the height of one row.
*
* A ToolbarLayout lets each component assume its natural (preferred) size.
*
* NOTE: This class was initially a subclass of FlowLayout, but we
* encountered problems using that approach.
*
* @version 0.10, 1999-04-27
* @author Peter Armstrong
* @author Tony Johnson
*/
public class ToolbarLayout implements LayoutManager, java.io.Serializable {
/**
* This value indicates that each row of components
* should be left-justified.
*/
public static final int LEFT = 0;
/**
* This value indicates that each row of components
* should be centered.
*/
public static final int CENTER = 1;
/**
* This value indicates that each row of components
* should be right-justified.
*/
public static final int RIGHT = 2;
int align;
int hgap;
int vgap;
/**
* Constructs a new ToolbarLayout with a left alignment and a
* default 5-unit horizontal and vertical gap.
*/
public ToolbarLayout() {
this(LEFT, 5, 5);
}
/**
* Constructs a new ToolbarLayout with the specified alignment and a
* default 5-unit horizontal and vertical gap.
* The value of the alignment argument must be one of
* <code>ToolbarLayout.LEFT</code>, <code>ToolbarLayout.RIGHT</code>,
* or <code>ToolbarLayout.CENTER</code>.
* @param align the alignment value
*/
public ToolbarLayout(int align) {
this(align, 5, 5);
}
/**
* Creates a new ToolbarLayout with the indicated alignment
* and the indicated horizontal and vertical gaps.
* <p>
* The value of the alignment argument must be one of
* <code>ToolbarLayout.LEFT</code>, <code>ToolbarLayout.RIGHT</code>,
* or <code>ToolbarLayout.CENTER</code>.
* @param align the alignment value.
* @param hgap the horizontal gap between components.
* @param vgap the vertical gap between components.
*/
public ToolbarLayout(int align, int hgap, int vgap) {
this.align = align;
this.hgap = hgap;
this.vgap = vgap;
}
/**
* Gets the alignment for this layout.
* Possible values are <code>ToolbarLayout.LEFT</code>,
* <code>ToolbarLayout.RIGHT</code>, or <code>ToolbarLayout.CENTER</code>.
* @return the alignment value for this layout.
* @see ToolbarLayout#setAlignment
*/
public int getAlignment() {
return align;
}
/**
* Sets the alignment for this layout.
* Possible values are <code>ToolbarLayout.LEFT</code>,
* <code>ToolbarLayout.RIGHT</code>, and <code>ToolbarLayout.CENTER</code>.
* @param align the alignment value.
* @see ToolbarLayout#getAlignment
*/
public void setAlignment(int align) {
this.align = align;
}
/**
* Gets the horizontal gap between components.
* @return the horizontal gap between components.
* @see ToolbarLayout#setHgap
*/
public int getHgap() {
return hgap;
}
/**
* Sets the horizontal gap between components.
* @param hgap the horizontal gap between components
* @see ToolbarLayout#getHgap
*/
public void setHgap(int hgap) {
this.hgap = hgap;
}
/**
* Gets the vertical gap between components.
* @return the vertical gap between components.
* @see ToolbarLayout#setVgap
*/
public int getVgap() {
return vgap;
}
/**
* Sets the vertical gap between components.
* @param vgap the vertical gap between components
* @see ToolbarLayout#getVgap
*/
public void setVgap(int vgap) {
this.vgap = vgap;
}
/**
* Adds the specified component to the layout. Sets the orientation to be horizontal.
* @param name the name of the component
* @param comp the component to be added
*/
public void addLayoutComponent(String name, Component comp) {
try {
((JToolBar)comp).setOrientation(JToolBar.HORIZONTAL);
} catch (Exception e){
}
}
/**
* Removes the specified component from the layout. Not used by
* this class.
* @param comp the component to remove
* @see java.awt.Container#removeAll
*/
public void removeLayoutComponent(Component comp) {
}
/**
* Returns the preferred dimensions for this layout given the components
* in the specified target container. This method is the difference
* between ToolbarLayout and FlowLayout.
* @param target the component which needs to be laid out
* @return the preferred dimensions to lay out the
* subcomponents of the specified container.
* @see Container
* @see #minimumLayoutSize
* @see java.awt.Container#getPreferredSize
*/
public Dimension preferredLayoutSize(Container target) {
synchronized (target.getTreeLock()) {
Dimension dim = new Dimension(0, 0);
int nmembers = target.getComponentCount();
Insets insets = target.getInsets();
int numRows = 1; //the number of rows
int rowSumWidth = insets.left + insets.right; //the width of the row so far
int rowMaxWidth = target.getSize().width; //the width that the ToolbarLayout is in
int rowHeight = 0; //the height of each row
int numOnRow = 0; //the number of components on the row
for (int i = 0 ; i < nmembers ; i++) {
Component m = target.getComponent(i);
if (m.isVisible()) {
Dimension d = m.getPreferredSize();
rowHeight = Math.max(rowHeight, d.height); //make each row the height of the biggest component of all
if (i > 0) {
rowSumWidth += hgap;//add on the pre-spacing if this is not the first component
}
rowSumWidth += d.width; //add the width of the component
//if it overflowed and if there are components already on this row then bump this component to next row
if ((rowSumWidth + hgap) > rowMaxWidth) {
if (numOnRow > 0) {
numRows++;
rowSumWidth = insets.left + insets.right + d.width;
numOnRow = 0;//reset the number of components on the next row (we ++ no matter what later)
}
}
numOnRow++;//add this component to the count of the number on the row
}
}
dim.width = rowMaxWidth;
dim.height = insets.top + insets.bottom + numRows*rowHeight + vgap*(numRows + 1);
return dim;
}
}
/**
* Returns the minimum dimensions needed to layout the components
* contained in the specified target container.
* @param target the component which needs to be laid out
* @return the minimum dimensions to lay out the
* subcomponents of the specified container.
* @see #preferredLayoutSize
* @see java.awt.Container
* @see java.awt.Container#doLayout
*/
public Dimension minimumLayoutSize(Container target) {
synchronized (target.getTreeLock()) {
Dimension dim = new Dimension(0, 0);
int nmembers = target.getComponentCount();
for (int i = 0 ; i < nmembers ; i++) {
Component m = target.getComponent(i);
if (m.isVisible()) {
Dimension d = m.getMinimumSize();
dim.height = Math.max(dim.height, d.height);
if (i > 0) {
dim.width += hgap;
}
dim.width += d.width;
}
}
Insets insets = target.getInsets();
dim.width += insets.left + insets.right + hgap*2;
dim.height += insets.top + insets.bottom + vgap*2;
return dim;
}
}
/**
* Centers the elements in the specified row, if there is any slack.
* @param target the component which needs to be moved
* @param x the x coordinate
* @param y the y coordinate
* @param width the width dimensions
* @param height the height dimensions
* @param rowStart the beginning of the row
* @param rowEnd the the ending of the row
*/
private void moveComponents(Container target, int x, int y, int width, int height, int rowStart, int rowEnd) {
synchronized (target.getTreeLock()) {
switch (align) {
case LEFT:
break;
case CENTER:
x += width / 2;
break;
case RIGHT:
x += width;
break;
}
for (int i = rowStart ; i < rowEnd ; i++) {
Component m = target.getComponent(i);
if (m.isVisible()) {
m.setLocation(x, y + (height - m.getSize().height) / 2);//JDK1.2 porting: replace with getHeight()
x += hgap + m.getSize().width; //JDK1.2 porting: replace with getWidth()
}
}
}
}
/**
* Lays out the container. This method lets each component take
* its preferred size by reshaping the components in the
* target container in order to satisfy the constraints of
* this <code>ToolbarLayout</code> object.
* @param target the specified component being laid out.
* @see Container
* @see java.awt.Container#doLayout
*/
public void layoutContainer(Container target) {
synchronized (target.getTreeLock()) {
Insets insets = target.getInsets();
int maxwidth = target.getSize().width - (insets.left + insets.right + hgap*2);//JDK1.2 porting: replace with getWidth()
int nmembers = target.getComponentCount();
int x = 0, y = insets.top + vgap;
int rowh = 0, start = 0;
for (int i = 0 ; i < nmembers ; i++) {
Component m = target.getComponent(i);
if (m.isVisible()) {
Dimension d = m.getPreferredSize();
m.setSize(d.width, d.height);
if ((x == 0) || ((x + d.width) <= maxwidth)) {
if (x > 0) {
x += hgap;
}
x += d.width;
rowh = Math.max(rowh, d.height);
} else {
moveComponents(target, insets.left + hgap, y, maxwidth - x, rowh, start, i);
x = d.width;
y += vgap + rowh;
rowh = d.height;
start = i;
}
}
}
moveComponents(target, insets.left + hgap, y, maxwidth - x, rowh, start, nmembers);
}
}
/**
* Returns a string representation of this <code>ToolbarLayout</code>
* object and its values.
* @return a string representation of this layout.
*/
public String toString() {
String str = "";
switch (align) {
case LEFT: str = ",align=left"; break;
case CENTER: str = ",align=center"; break;
case RIGHT: str = ",align=right"; break;
}
return getClass().getName() + "[hgap=" + hgap + ",vgap=" + vgap + str + "]";
}
}