Stack Layout, uses an orientation to determine if the contents should be arranged horizontally or vertically.
/*
* StackLayout.java
* 2005-07-15
*/
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Insets;
import java.awt.LayoutManager;
import javax.swing.JSeparator;
import javax.swing.JToolBar;
import javax.swing.SwingConstants;
/**
* Similar to BoxLayout, uses an orientation to determine if the contents
* should be arranged horizontally or vertically. By default, Resizes each
* item to equal width or height (depending on the orientation) based on the
* maximum preferred width or height of all items.
* @author Christopher Bach
*/
public class StackLayout implements LayoutManager
{
public static final int HORIZONTAL = SwingConstants.HORIZONTAL;
public static final int VERTICAL = SwingConstants.VERTICAL;
private int ourOrientation = HORIZONTAL;
private int ourSpacing = 0;
private boolean ourDepthsMatched = true;
private boolean ourLengthsMatched = false;
private boolean ourFill = false;
private boolean ourDrop = false;
private int ourSqueezeFactor = 100;
/**
* Creates a new StackLayout with a horizontal orientation.
*/
public StackLayout()
{
}
/**
* Creates a new StackLayout with the specified orientation.
*/
public StackLayout(int orientation)
{
setOrientation(orientation);
}
/**
* Creates a new StackLayout with the specified orientation and spacing.
*/
public StackLayout(int orientation, int spacing)
{
setOrientation(orientation);
setSpacing(spacing);
}
/**
* Creates a new StackLayout matching the component lengths and
* depths as indicated.
*/
public StackLayout(boolean matchLengths, boolean matchDepths)
{
setMatchesComponentLengths(matchLengths);
setMatchesComponentDepths(matchDepths);
}
/**
* Creates a new StackLayout with the specified orientation
* and spacing, matching the component lengths and depths
* as indicated.
*/
public StackLayout(int orientation, int spacing,
boolean matchLengths, boolean matchDepths)
{
setOrientation(orientation);
setSpacing(spacing);
setMatchesComponentLengths(matchLengths);
setMatchesComponentDepths(matchDepths);
}
/**
* Sets this StackLayout's orientation, either
* SwingConstants.HORIZONTAL or SwingConstants.VERTICAL.
*/
public void setOrientation(int orientation)
{
if (orientation == HORIZONTAL || orientation == VERTICAL)
{
ourOrientation = orientation;
}
}
/**
* Returns this StackLayout's orientation, either
* SwingConstants.HORIZONTAL or SwingConstants.VERTICAL.
*/
public int getOrientation()
{
return ourOrientation;
}
/**
* Sets the spacing between components that this StackLayout uses
* when laying out the components.
*/
public void setSpacing(int spacing)
{
ourSpacing = Math.max(0, spacing);
}
/**
* Returns the spacing between components that this StackLayout uses
* when laying out the components.
*/
public int getSpacing()
{
return ourSpacing;
}
/**
* Sets whether or not the last component in the stack
* should be stretched to fill any remaining space within
* the parent container. The default value is false.
*/
public void setFillsTrailingSpace(boolean shouldFill)
{
ourFill = shouldFill;
}
/**
* Returns whether or not the last component in the stack
* should be stretched to fill any remaining space within
* the parent container.
*/
public boolean fillsTrailingSpace()
{
return ourFill;
}
/**
* Sets whether or not components in the stack that do not
* fit in the parent container should be left out of the layout.
* The default value is false;
*/
public void setDropsPartialComponents(boolean shouldDrop)
{
ourDrop = shouldDrop;
}
/**
* Returns whether or not components in the stack that do not
* fit in the parent container should be left out of the layout.
*/
public boolean dropsPartialComponents()
{
return ourDrop;
}
/**
* Sets whether or not all components in the stack will be sized
* to the same height (when in a horizontal orientation) or width
* (when in a vertical orientation). The default value is true.
*/
public void setMatchesComponentDepths(boolean match)
{
ourDepthsMatched = match;
}
/**
* Returns whether or not all components in the stack will be sized
* to the same height (when in a horizontal orientation) or width
* (when in a vertical orientation).
*/
public boolean matchesComponentDepths()
{
return ourDepthsMatched;
}
/**
* Sets whether or not all components in the stack will be sized
* to the same width (when in a horizontal orientation) or height
* (when in a vertical orientation). The default value is false.
*/
public void setMatchesComponentLengths(boolean match)
{
ourLengthsMatched = match;
}
/**
* Returns whether or not all components in the stack will be sized
* to the same width (when in a horizontal orientation) or height
* (when in a vertical orientation).
*/
public boolean matchesComponentLengths()
{
return ourLengthsMatched;
}
/**
* Sets the percentage of a component's preferred size that it
* may be squeezed in order to attempt to fit all components
* into the layout. The squeeze factor will only be applied
* when this layout is set to match component lengths.
*
* For example, if the parent container is 100 pixels wide
* and holds two buttons, the largest having a preferred
* width of 80 pixels, a squeeze factor of 50 will allow each
* button to be sized to as small as 40 pixels wide (50 percent
* of the preferred width.
*
* The default value is 100.
*/
public void setSqueezeFactor(int factor)
{
if (factor < 0) ourSqueezeFactor = 0;
else if (factor > 100) ourSqueezeFactor = 100;
else ourSqueezeFactor = factor;
}
/**
* Returns the percentage of a component's preferred size that it
* may be squeezed in order to attempt to fit all components
* into the layout.
*/
public int getSqueezeFactor()
{
return ourSqueezeFactor;
}
////// LayoutManager implementation //////
/**
* Adds the specified component with the specified name to this layout.
*/
public void addLayoutComponent(String name, Component comp)
{
}
/**
* Removes the specified component from this layout.
*/
public void removeLayoutComponent(Component comp)
{
}
/**
* Returns the preferred size for this layout to arrange the
* indicated parent's children.
*/
public Dimension preferredLayoutSize(Container parent)
{
if (parent instanceof JToolBar)
{
setOrientation( ((JToolBar)parent).getOrientation() );
}
return preferredLayoutSize(parent, ourOrientation);
}
/**
* Returns the preferred size for this layout to arrange the
* indicated parent's children at the specified orientation.
*/
// public, because it's useful - not one of the LayoutManager methods
public Dimension preferredLayoutSize(Container parent, int orientation)
{
synchronized (parent.getTreeLock())
{
Component[] comps = parent.getComponents();
Dimension total = new Dimension(0, 0);
int depth = calculatePreferredDepth(comps, orientation);
int length = ( ourLengthsMatched ?
calculateAdjustedLength(comps, orientation, ourSpacing)
: calculatePreferredLength(comps, orientation, ourSpacing) );
total.width = (orientation == HORIZONTAL ? length : depth);
total.height = (orientation == HORIZONTAL ? depth : length);
Insets in = parent.getInsets();
total.width += in.left + in.right;
total.height += in.top + in.bottom;
return total;
}
}
/**
* Returns the minimum size for this layout to arrange the
* indicated parent's children at the specified orientation.
*/
public Dimension minimumLayoutSize(Container parent)
{
synchronized (parent.getTreeLock())
{
if (parent instanceof JToolBar)
{
setOrientation( ((JToolBar)parent).getOrientation() );
}
Component[] comps = parent.getComponents();
Dimension total = new Dimension(0, 0);
int depth = calculatePreferredDepth(comps, ourOrientation);
int length = calculateMinimumLength(comps, ourOrientation, ourSpacing);
total.width = (ourOrientation == HORIZONTAL ? length : depth);
total.height = (ourOrientation == HORIZONTAL ? depth : length);
Insets in = parent.getInsets();
total.width += in.left + in.right;
total.height += in.top + in.bottom;
return total;
}
}
/**
* Lays out the child components within the indicated parent container.
*/
public void layoutContainer(Container parent)
{
synchronized (parent.getTreeLock())
{
if (parent instanceof JToolBar)
{
setOrientation( ((JToolBar)parent).getOrientation() );
}
layoutComponents(parent);
}
}
private void layoutComponents(Container parent)
{
Component[] components = parent.getComponents();
Insets in = parent.getInsets();
int maxHeight = parent.getHeight() - in.top - in.bottom;
int maxWidth = parent.getWidth() - in.left - in.right;
boolean horiz = (ourOrientation == HORIZONTAL);
int totalDepth = calculatePreferredDepth(components, ourOrientation);
totalDepth = Math.max( totalDepth, (horiz ? maxHeight : maxWidth) );
int prefLength = ( ourLengthsMatched ?
calculateAdjustedLength(components, ourOrientation, ourSpacing)
: calculatePreferredLength(components, ourOrientation, ourSpacing) );
int totalLength = Math.min( prefLength, (horiz ? maxWidth : maxHeight) );
int a = (horiz ? in.left : in.top);
int b = (horiz ? in.top : in.left);
int l = 0, d = 0, sum = 0;
int matchedLength = 0;
Dimension prefsize = null;
if (ourLengthsMatched)
{
matchedLength = ( horiz ? getMaxPrefWidth(components)
: getMaxPrefHeight(components) );
if (prefLength > totalLength && ourSqueezeFactor < 100)
{
int minLength = calculateMinimumLength(components,
ourOrientation, ourSpacing);
if (minLength >= totalLength)
{
matchedLength = (matchedLength * ourSqueezeFactor) / 100;
}
else
{
int numSeparators = countSeparators(components);
int numComponents = components.length - numSeparators;
int diff = (prefLength - totalLength) / numComponents;
if ((prefLength - totalLength) % numComponents > 0) diff++;
matchedLength -= diff;
}
}
}
for (int i=0; i < components.length; i++)
{
prefsize = components[i].getPreferredSize();
if (!ourLengthsMatched) l = (horiz ? prefsize.width : prefsize.height);
else l = matchedLength;
if (components[i] instanceof JSeparator)
{
// l = Math.min(prefsize.width, prefsize.height);
l = (horiz ? prefsize.width : prefsize.height);
d = totalDepth;
sum += l;
if (ourDrop && sum > totalLength) l = 0;
}
else
{
sum += l;
if (ourDrop && sum > totalLength) l = 0;
else if (ourFill && !ourLengthsMatched && i == components.length - 1)
{
l = Math.max( l, (horiz ? maxWidth : maxHeight) );
}
if (ourDepthsMatched) d = totalDepth;
else d = (horiz ? prefsize.height : prefsize.width);
}
if (horiz) components[i].setBounds(a, b + (totalDepth - d) / 2, l, d);
else components[i].setBounds(b + (totalDepth - d) / 2, a, d, l);
a += l + ourSpacing;
sum += ourSpacing;
}
}
/**
* Returns the largest preferred width of the provided components.
*/
private int getMaxPrefWidth(Component[] components)
{
int maxWidth = 0;
int componentWidth = 0;
Dimension d = null;
for (int i=0; i < components.length; i++)
{
d = components[i].getPreferredSize();
componentWidth = d.width;
if (components[i] instanceof JSeparator)
{
componentWidth = Math.min(d.width, d.height);
}
maxWidth = Math.max(maxWidth, componentWidth);
}
return maxWidth;
}
/**
* Returns the largest preferred height of the provided components.
*/
private int getMaxPrefHeight(Component[] components)
{
int maxHeight = 0;
int componentHeight = 0;
Dimension d = null;
for (int i=0; i < components.length; i++)
{
d = components[i].getPreferredSize();
componentHeight = d.height;
if (components[i] instanceof JSeparator)
{
componentHeight = Math.min(d.width, d.height);
}
else maxHeight = Math.max(maxHeight, componentHeight);
}
return maxHeight;
}
/**
* Calculates the preferred "length" of this layout for the provided
* components based on the largest component preferred size.
*/
private int calculateAdjustedLength(Component[] components,
int orientation, int spacing)
{
int total = 0;
int componentLength = ( orientation == HORIZONTAL ?
getMaxPrefWidth(components) : getMaxPrefHeight(components) );
for (int i=0; i < components.length; i++)
{
if (components[i] instanceof JSeparator)
{
Dimension d = components[i].getPreferredSize();
// total += Math.min(d.width, d.height);
total += (orientation == HORIZONTAL ? d.width : d.height);
}
else total += componentLength;
}
int gaps = Math.max(0, spacing * (components.length - 1));
total += gaps;
return total;
}
/**
* Calculates the minimum "length" of this layout for the provided
* components, taking the squeeze factor into account when necessary.
*/
private int calculateMinimumLength(Component[] components,
int orientation, int spacing)
{
if (!ourLengthsMatched) return calculatePreferredLength(
components, orientation, spacing );
if (ourSqueezeFactor == 100) return calculateAdjustedLength(
components, orientation, spacing);
int total = 0;
int componentLength = ( orientation == HORIZONTAL ?
getMaxPrefWidth(components) : getMaxPrefHeight(components) );
componentLength = (componentLength * ourSqueezeFactor) / 100;
for (int i=0; i < components.length; i++)
{
if (components[i] instanceof JSeparator)
{
Dimension d = components[i].getPreferredSize();
// total += Math.min(d.width, d.height);
total += (orientation == HORIZONTAL ? d.width : d.height);
}
else total += componentLength;
}
int gaps = Math.max(0, spacing * (components.length - 1));
total += gaps;
return total;
}
/**
* Calculates the preferred "length" of this layout for the provided
* components.
*/
private int calculatePreferredLength(Component[] components,
int orientation, int spacing)
{
int total = 0;
Dimension d = null;
for (int i=0; i < components.length; i++)
{
d = components[i].getPreferredSize();
// if (components[i] instanceof JSeparator)
// {
// total += Math.min(d.width, d.height);
// }
//
// else
total += (orientation == HORIZONTAL ? d.width : d.height);
}
int gaps = Math.max(0, spacing * (components.length - 1));
total += gaps;
return total;
}
/**
* Returns the preferred "depth" of this layout for the provided
* components.
*/
private int calculatePreferredDepth(Component[] components, int orientation)
{
if (orientation == HORIZONTAL) return getMaxPrefHeight(components);
else if (orientation == VERTICAL) return getMaxPrefWidth(components);
else return 0;
}
private int countSeparators(Component[] components)
{
int count = 0;
for (int i=0; i < components.length; i++)
{
if (components[i] instanceof JSeparator) count++;
}
return count;
}
}
Related examples in the same category
