You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
697 lines
22 KiB
697 lines
22 KiB
/*
|
|
* Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
|
|
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*
|
|
*/
|
|
package java.awt;
|
|
|
|
import java.io.ObjectInputStream;
|
|
import java.io.IOException;
|
|
|
|
/**
|
|
* A flow layout arranges components in a directional flow, much
|
|
* like lines of text in a paragraph. The flow direction is
|
|
* determined by the container's <code>componentOrientation</code>
|
|
* property and may be one of two values:
|
|
* <ul>
|
|
* <li><code>ComponentOrientation.LEFT_TO_RIGHT</code>
|
|
* <li><code>ComponentOrientation.RIGHT_TO_LEFT</code>
|
|
* </ul>
|
|
* Flow layouts are typically used
|
|
* to arrange buttons in a panel. It arranges buttons
|
|
* horizontally until no more buttons fit on the same line.
|
|
* The line alignment is determined by the <code>align</code>
|
|
* property. The possible values are:
|
|
* <ul>
|
|
* <li>{@link #LEFT LEFT}
|
|
* <li>{@link #RIGHT RIGHT}
|
|
* <li>{@link #CENTER CENTER}
|
|
* <li>{@link #LEADING LEADING}
|
|
* <li>{@link #TRAILING TRAILING}
|
|
* </ul>
|
|
* <p>
|
|
* For example, the following picture shows an applet using the flow
|
|
* layout manager (its default layout manager) to position three buttons:
|
|
* <p>
|
|
* <img src="doc-files/FlowLayout-1.gif"
|
|
* ALT="Graphic of Layout for Three Buttons"
|
|
* style="float:center; margin: 7px 10px;">
|
|
* <p>
|
|
* Here is the code for this applet:
|
|
*
|
|
* <hr><blockquote><pre>
|
|
* import java.awt.*;
|
|
* import java.applet.Applet;
|
|
*
|
|
* public class myButtons extends Applet {
|
|
* Button button1, button2, button3;
|
|
* public void init() {
|
|
* button1 = new Button("Ok");
|
|
* button2 = new Button("Open");
|
|
* button3 = new Button("Close");
|
|
* add(button1);
|
|
* add(button2);
|
|
* add(button3);
|
|
* }
|
|
* }
|
|
* </pre></blockquote><hr>
|
|
* <p>
|
|
* A flow layout lets each component assume its natural (preferred) size.
|
|
*
|
|
* @author Arthur van Hoff
|
|
* @author Sami Shaio
|
|
* @since JDK1.0
|
|
* @see ComponentOrientation
|
|
*/
|
|
public class FlowLayout 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;
|
|
|
|
/**
|
|
* This value indicates that each row of components
|
|
* should be justified to the leading edge of the container's
|
|
* orientation, for example, to the left in left-to-right orientations.
|
|
*
|
|
* @see java.awt.Component#getComponentOrientation
|
|
* @see java.awt.ComponentOrientation
|
|
* @since 1.2
|
|
*/
|
|
public static final int LEADING = 3;
|
|
|
|
/**
|
|
* This value indicates that each row of components
|
|
* should be justified to the trailing edge of the container's
|
|
* orientation, for example, to the right in left-to-right orientations.
|
|
*
|
|
* @see java.awt.Component#getComponentOrientation
|
|
* @see java.awt.ComponentOrientation
|
|
* @since 1.2
|
|
*/
|
|
public static final int TRAILING = 4;
|
|
|
|
/**
|
|
* <code>align</code> is the property that determines
|
|
* how each row distributes empty space.
|
|
* It can be one of the following values:
|
|
* <ul>
|
|
* <li><code>LEFT</code>
|
|
* <li><code>RIGHT</code>
|
|
* <li><code>CENTER</code>
|
|
* </ul>
|
|
*
|
|
* @serial
|
|
* @see #getAlignment
|
|
* @see #setAlignment
|
|
*/
|
|
int align; // This is for 1.1 serialization compatibility
|
|
|
|
/**
|
|
* <code>newAlign</code> is the property that determines
|
|
* how each row distributes empty space for the Java 2 platform,
|
|
* v1.2 and greater.
|
|
* It can be one of the following three values:
|
|
* <ul>
|
|
* <li><code>LEFT</code>
|
|
* <li><code>RIGHT</code>
|
|
* <li><code>CENTER</code>
|
|
* <li><code>LEADING</code>
|
|
* <li><code>TRAILING</code>
|
|
* </ul>
|
|
*
|
|
* @serial
|
|
* @since 1.2
|
|
* @see #getAlignment
|
|
* @see #setAlignment
|
|
*/
|
|
int newAlign; // This is the one we actually use
|
|
|
|
/**
|
|
* The flow layout manager allows a seperation of
|
|
* components with gaps. The horizontal gap will
|
|
* specify the space between components and between
|
|
* the components and the borders of the
|
|
* <code>Container</code>.
|
|
*
|
|
* @serial
|
|
* @see #getHgap()
|
|
* @see #setHgap(int)
|
|
*/
|
|
int hgap;
|
|
|
|
/**
|
|
* The flow layout manager allows a seperation of
|
|
* components with gaps. The vertical gap will
|
|
* specify the space between rows and between the
|
|
* the rows and the borders of the <code>Container</code>.
|
|
*
|
|
* @serial
|
|
* @see #getHgap()
|
|
* @see #setHgap(int)
|
|
*/
|
|
int vgap;
|
|
|
|
/**
|
|
* If true, components will be aligned on their baseline.
|
|
*/
|
|
private boolean alignOnBaseline;
|
|
|
|
/*
|
|
* JDK 1.1 serialVersionUID
|
|
*/
|
|
private static final long serialVersionUID = -7262534875583282631L;
|
|
|
|
/**
|
|
* Constructs a new <code>FlowLayout</code> with a centered alignment and a
|
|
* default 5-unit horizontal and vertical gap.
|
|
*/
|
|
public FlowLayout() {
|
|
this(CENTER, 5, 5);
|
|
}
|
|
|
|
/**
|
|
* Constructs a new <code>FlowLayout</code> with the specified
|
|
* alignment and a default 5-unit horizontal and vertical gap.
|
|
* The value of the alignment argument must be one of
|
|
* <code>FlowLayout.LEFT</code>, <code>FlowLayout.RIGHT</code>,
|
|
* <code>FlowLayout.CENTER</code>, <code>FlowLayout.LEADING</code>,
|
|
* or <code>FlowLayout.TRAILING</code>.
|
|
* @param align the alignment value
|
|
*/
|
|
public FlowLayout(int align) {
|
|
this(align, 5, 5);
|
|
}
|
|
|
|
/**
|
|
* Creates a new flow layout manager with the indicated alignment
|
|
* and the indicated horizontal and vertical gaps.
|
|
* <p>
|
|
* The value of the alignment argument must be one of
|
|
* <code>FlowLayout.LEFT</code>, <code>FlowLayout.RIGHT</code>,
|
|
* <code>FlowLayout.CENTER</code>, <code>FlowLayout.LEADING</code>,
|
|
* or <code>FlowLayout.TRAILING</code>.
|
|
* @param align the alignment value
|
|
* @param hgap the horizontal gap between components
|
|
* and between the components and the
|
|
* borders of the <code>Container</code>
|
|
* @param vgap the vertical gap between components
|
|
* and between the components and the
|
|
* borders of the <code>Container</code>
|
|
*/
|
|
public FlowLayout(int align, int hgap, int vgap) {
|
|
this.hgap = hgap;
|
|
this.vgap = vgap;
|
|
setAlignment(align);
|
|
}
|
|
|
|
/**
|
|
* Gets the alignment for this layout.
|
|
* Possible values are <code>FlowLayout.LEFT</code>,
|
|
* <code>FlowLayout.RIGHT</code>, <code>FlowLayout.CENTER</code>,
|
|
* <code>FlowLayout.LEADING</code>,
|
|
* or <code>FlowLayout.TRAILING</code>.
|
|
* @return the alignment value for this layout
|
|
* @see java.awt.FlowLayout#setAlignment
|
|
* @since JDK1.1
|
|
*/
|
|
public int getAlignment() {
|
|
return newAlign;
|
|
}
|
|
|
|
/**
|
|
* Sets the alignment for this layout.
|
|
* Possible values are
|
|
* <ul>
|
|
* <li><code>FlowLayout.LEFT</code>
|
|
* <li><code>FlowLayout.RIGHT</code>
|
|
* <li><code>FlowLayout.CENTER</code>
|
|
* <li><code>FlowLayout.LEADING</code>
|
|
* <li><code>FlowLayout.TRAILING</code>
|
|
* </ul>
|
|
* @param align one of the alignment values shown above
|
|
* @see #getAlignment()
|
|
* @since JDK1.1
|
|
*/
|
|
public void setAlignment(int align) {
|
|
this.newAlign = align;
|
|
|
|
// this.align is used only for serialization compatibility,
|
|
// so set it to a value compatible with the 1.1 version
|
|
// of the class
|
|
|
|
switch (align) {
|
|
case LEADING:
|
|
this.align = LEFT;
|
|
break;
|
|
case TRAILING:
|
|
this.align = RIGHT;
|
|
break;
|
|
default:
|
|
this.align = align;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Gets the horizontal gap between components
|
|
* and between the components and the borders
|
|
* of the <code>Container</code>
|
|
*
|
|
* @return the horizontal gap between components
|
|
* and between the components and the borders
|
|
* of the <code>Container</code>
|
|
* @see java.awt.FlowLayout#setHgap
|
|
* @since JDK1.1
|
|
*/
|
|
public int getHgap() {
|
|
return hgap;
|
|
}
|
|
|
|
/**
|
|
* Sets the horizontal gap between components and
|
|
* between the components and the borders of the
|
|
* <code>Container</code>.
|
|
*
|
|
* @param hgap the horizontal gap between components
|
|
* and between the components and the borders
|
|
* of the <code>Container</code>
|
|
* @see java.awt.FlowLayout#getHgap
|
|
* @since JDK1.1
|
|
*/
|
|
public void setHgap(int hgap) {
|
|
this.hgap = hgap;
|
|
}
|
|
|
|
/**
|
|
* Gets the vertical gap between components and
|
|
* between the components and the borders of the
|
|
* <code>Container</code>.
|
|
*
|
|
* @return the vertical gap between components
|
|
* and between the components and the borders
|
|
* of the <code>Container</code>
|
|
* @see java.awt.FlowLayout#setVgap
|
|
* @since JDK1.1
|
|
*/
|
|
public int getVgap() {
|
|
return vgap;
|
|
}
|
|
|
|
/**
|
|
* Sets the vertical gap between components and between
|
|
* the components and the borders of the <code>Container</code>.
|
|
*
|
|
* @param vgap the vertical gap between components
|
|
* and between the components and the borders
|
|
* of the <code>Container</code>
|
|
* @see java.awt.FlowLayout#getVgap
|
|
* @since JDK1.1
|
|
*/
|
|
public void setVgap(int vgap) {
|
|
this.vgap = vgap;
|
|
}
|
|
|
|
/**
|
|
* Sets whether or not components should be vertically aligned along their
|
|
* baseline. Components that do not have a baseline will be centered.
|
|
* The default is false.
|
|
*
|
|
* @param alignOnBaseline whether or not components should be
|
|
* vertically aligned on their baseline
|
|
* @since 1.6
|
|
*/
|
|
public void setAlignOnBaseline(boolean alignOnBaseline) {
|
|
this.alignOnBaseline = alignOnBaseline;
|
|
}
|
|
|
|
/**
|
|
* Returns true if components are to be vertically aligned along
|
|
* their baseline. The default is false.
|
|
*
|
|
* @return true if components are to be vertically aligned along
|
|
* their baseline
|
|
* @since 1.6
|
|
*/
|
|
public boolean getAlignOnBaseline() {
|
|
return alignOnBaseline;
|
|
}
|
|
|
|
/**
|
|
* Adds the specified component to the layout.
|
|
* Not used by this class.
|
|
* @param name the name of the component
|
|
* @param comp the component to be added
|
|
*/
|
|
public void addLayoutComponent(String name, Component comp) {
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
* <i>visible</i> components in the specified target container.
|
|
*
|
|
* @param target the container that 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();
|
|
boolean firstVisibleComponent = true;
|
|
boolean useBaseline = getAlignOnBaseline();
|
|
int maxAscent = 0;
|
|
int maxDescent = 0;
|
|
|
|
for (int i = 0 ; i < nmembers ; i++) {
|
|
Component m = target.getComponent(i);
|
|
if (m.isVisible()) {
|
|
Dimension d = m.getPreferredSize();
|
|
dim.height = Math.max(dim.height, d.height);
|
|
if (firstVisibleComponent) {
|
|
firstVisibleComponent = false;
|
|
} else {
|
|
dim.width += hgap;
|
|
}
|
|
dim.width += d.width;
|
|
if (useBaseline) {
|
|
int baseline = m.getBaseline(d.width, d.height);
|
|
if (baseline >= 0) {
|
|
maxAscent = Math.max(maxAscent, baseline);
|
|
maxDescent = Math.max(maxDescent, d.height - baseline);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (useBaseline) {
|
|
dim.height = Math.max(maxAscent + maxDescent, dim.height);
|
|
}
|
|
Insets insets = target.getInsets();
|
|
dim.width += insets.left + insets.right + hgap*2;
|
|
dim.height += insets.top + insets.bottom + vgap*2;
|
|
return dim;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns the minimum dimensions needed to layout the <i>visible</i>
|
|
* components contained in the specified target container.
|
|
* @param target the container that 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()) {
|
|
boolean useBaseline = getAlignOnBaseline();
|
|
Dimension dim = new Dimension(0, 0);
|
|
int nmembers = target.getComponentCount();
|
|
int maxAscent = 0;
|
|
int maxDescent = 0;
|
|
boolean firstVisibleComponent = true;
|
|
|
|
for (int i = 0 ; i < nmembers ; i++) {
|
|
Component m = target.getComponent(i);
|
|
if (m.visible) {
|
|
Dimension d = m.getMinimumSize();
|
|
dim.height = Math.max(dim.height, d.height);
|
|
if (firstVisibleComponent) {
|
|
firstVisibleComponent = false;
|
|
} else {
|
|
dim.width += hgap;
|
|
}
|
|
dim.width += d.width;
|
|
if (useBaseline) {
|
|
int baseline = m.getBaseline(d.width, d.height);
|
|
if (baseline >= 0) {
|
|
maxAscent = Math.max(maxAscent, baseline);
|
|
maxDescent = Math.max(maxDescent,
|
|
dim.height - baseline);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (useBaseline) {
|
|
dim.height = Math.max(maxAscent + maxDescent, dim.height);
|
|
}
|
|
|
|
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
|
|
* @param useBaseline Whether or not to align on baseline.
|
|
* @param ascent Ascent for the components. This is only valid if
|
|
* useBaseline is true.
|
|
* @param descent Ascent for the components. This is only valid if
|
|
* useBaseline is true.
|
|
* @return actual row height
|
|
*/
|
|
private int moveComponents(Container target, int x, int y, int width, int height,
|
|
int rowStart, int rowEnd, boolean ltr,
|
|
boolean useBaseline, int[] ascent,
|
|
int[] descent) {
|
|
switch (newAlign) {
|
|
case LEFT:
|
|
x += ltr ? 0 : width;
|
|
break;
|
|
case CENTER:
|
|
x += width / 2;
|
|
break;
|
|
case RIGHT:
|
|
x += ltr ? width : 0;
|
|
break;
|
|
case LEADING:
|
|
break;
|
|
case TRAILING:
|
|
x += width;
|
|
break;
|
|
}
|
|
int maxAscent = 0;
|
|
int nonbaselineHeight = 0;
|
|
int baselineOffset = 0;
|
|
if (useBaseline) {
|
|
int maxDescent = 0;
|
|
for (int i = rowStart ; i < rowEnd ; i++) {
|
|
Component m = target.getComponent(i);
|
|
if (m.visible) {
|
|
if (ascent[i] >= 0) {
|
|
maxAscent = Math.max(maxAscent, ascent[i]);
|
|
maxDescent = Math.max(maxDescent, descent[i]);
|
|
}
|
|
else {
|
|
nonbaselineHeight = Math.max(m.getHeight(),
|
|
nonbaselineHeight);
|
|
}
|
|
}
|
|
}
|
|
height = Math.max(maxAscent + maxDescent, nonbaselineHeight);
|
|
baselineOffset = (height - maxAscent - maxDescent) / 2;
|
|
}
|
|
for (int i = rowStart ; i < rowEnd ; i++) {
|
|
Component m = target.getComponent(i);
|
|
if (m.isVisible()) {
|
|
int cy;
|
|
if (useBaseline && ascent[i] >= 0) {
|
|
cy = y + baselineOffset + maxAscent - ascent[i];
|
|
}
|
|
else {
|
|
cy = y + (height - m.height) / 2;
|
|
}
|
|
if (ltr) {
|
|
m.setLocation(x, cy);
|
|
} else {
|
|
m.setLocation(target.width - x - m.width, cy);
|
|
}
|
|
x += m.width + hgap;
|
|
}
|
|
}
|
|
return height;
|
|
}
|
|
|
|
/**
|
|
* Lays out the container. This method lets each
|
|
* <i>visible</i> component take
|
|
* its preferred size by reshaping the components in the
|
|
* target container in order to satisfy the alignment of
|
|
* this <code>FlowLayout</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.width - (insets.left + insets.right + hgap*2);
|
|
int nmembers = target.getComponentCount();
|
|
int x = 0, y = insets.top + vgap;
|
|
int rowh = 0, start = 0;
|
|
|
|
boolean ltr = target.getComponentOrientation().isLeftToRight();
|
|
|
|
boolean useBaseline = getAlignOnBaseline();
|
|
int[] ascent = null;
|
|
int[] descent = null;
|
|
|
|
if (useBaseline) {
|
|
ascent = new int[nmembers];
|
|
descent = new int[nmembers];
|
|
}
|
|
|
|
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 (useBaseline) {
|
|
int baseline = m.getBaseline(d.width, d.height);
|
|
if (baseline >= 0) {
|
|
ascent[i] = baseline;
|
|
descent[i] = d.height - baseline;
|
|
}
|
|
else {
|
|
ascent[i] = -1;
|
|
}
|
|
}
|
|
if ((x == 0) || ((x + d.width) <= maxwidth)) {
|
|
if (x > 0) {
|
|
x += hgap;
|
|
}
|
|
x += d.width;
|
|
rowh = Math.max(rowh, d.height);
|
|
} else {
|
|
rowh = moveComponents(target, insets.left + hgap, y,
|
|
maxwidth - x, rowh, start, i, ltr,
|
|
useBaseline, ascent, descent);
|
|
x = d.width;
|
|
y += vgap + rowh;
|
|
rowh = d.height;
|
|
start = i;
|
|
}
|
|
}
|
|
}
|
|
moveComponents(target, insets.left + hgap, y, maxwidth - x, rowh,
|
|
start, nmembers, ltr, useBaseline, ascent, descent);
|
|
}
|
|
}
|
|
|
|
//
|
|
// the internal serial version which says which version was written
|
|
// - 0 (default) for versions before the Java 2 platform, v1.2
|
|
// - 1 for version >= Java 2 platform v1.2, which includes "newAlign" field
|
|
//
|
|
private static final int currentSerialVersion = 1;
|
|
/**
|
|
* This represent the <code>currentSerialVersion</code>
|
|
* which is bein used. It will be one of two values :
|
|
* <code>0</code> versions before Java 2 platform v1.2..
|
|
* <code>1</code> versions after Java 2 platform v1.2..
|
|
*
|
|
* @serial
|
|
* @since 1.2
|
|
*/
|
|
private int serialVersionOnStream = currentSerialVersion;
|
|
|
|
/**
|
|
* Reads this object out of a serialization stream, handling
|
|
* objects written by older versions of the class that didn't contain all
|
|
* of the fields we use now..
|
|
*/
|
|
private void readObject(ObjectInputStream stream)
|
|
throws IOException, ClassNotFoundException
|
|
{
|
|
stream.defaultReadObject();
|
|
|
|
if (serialVersionOnStream < 1) {
|
|
// "newAlign" field wasn't present, so use the old "align" field.
|
|
setAlignment(this.align);
|
|
}
|
|
serialVersionOnStream = currentSerialVersion;
|
|
}
|
|
|
|
/**
|
|
* Returns a string representation of this <code>FlowLayout</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;
|
|
case LEADING: str = ",align=leading"; break;
|
|
case TRAILING: str = ",align=trailing"; break;
|
|
}
|
|
return getClass().getName() + "[hgap=" + hgap + ",vgap=" + vgap + str + "]";
|
|
}
|
|
|
|
|
|
}
|