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[英]Jpanels with Gridbaglayout inside a JPanel with GridbagLayout problems
[英]Too many JPanels inside a JPanel (with GridBagLayout)
所以基本上如果我把JPanel
放在一個使用GridBagLayout
的JPanel
,我用setPreferredSize
限制大小,最終它達到了無法容納所有這些的點,並且它展示了附圖中顯示的行為:
我正在制作手風琴 。 這只是一個展示我遇到的問題的例子。 手風琴的每個部分都可以單獨打開,它們具有任意大小,可以隨時添加。 它很容易達到所有單個面板的高度,並將它們與總高度進行比較,但是當添加太多時,它表現出我所展示的嘎吱嘎吱的行為。 這也縮小了高度,因此更難以確定何時發生嘎吱嘎吱聲。 我必須緩存高度,並以某種方式預先計算新部件的高度。 最終目標是在添加新面板並且沒有足夠空間時移除舊面板。
有沒有一種簡單的方法來確定如果它沒有受到限制會有什么高度,或者可能是一種支持的方法來檢測何時發生這樣的嘎吱嘎吱(所以我可以在再次塗漆之前快速將其稀釋)? 使GridBagLayout
像其他布局一樣運行並且溢出到Hammerspace而不是壓縮的選項也可以工作。
代碼例如:
import java.awt.*;
import java.awt.event.*;
import javaisms.out;
import javax.swing.*;
public class FoldDrag extends JLayeredPane {
public TexturedPanel backingPanel = new TexturedPanel(new GridBagLayout(),"data/gui/grayerbricks.png");
static JPanel windowbase=new JPanel();
static JPanel restrictedpanel=new JPanel(new GridBagLayout());
GridBagConstraints gbc = new GridBagConstraints();
public FoldDrag() {
JButton addpan = new JButton("Add things");
windowbase.add(addpan);
windowbase.add(restrictedpanel);
restrictedpanel.setBackground(Color.red);
restrictedpanel.setPreferredSize(new Dimension(200,200));
gbc.weighty=1;
gbc.weightx=1;
gbc.gridx=0;
gbc.gridy=0;
gbc.gridheight=1;
gbc.gridwidth=1;
gbc.fill=GridBagConstraints.HORIZONTAL;
addpan.addActionListener(new ActionListener() {
int number=0;
@Override
public void actionPerformed(ActionEvent e)
{
number++;
gbc.gridy=number;
JPanel tmppanel = new JPanel();
tmppanel.setPreferredSize(new Dimension(100,30));
if(number%3==0)
tmppanel.setBackground(Color.blue);
if(number%3==1)
tmppanel.setBackground(Color.yellow);
if(number%3==2)
tmppanel.setBackground(Color.green);
restrictedpanel.add(tmppanel,gbc);
restrictedpanel.validate();
}
});
windowbase.setVisible(true);
}
private static void createAndShowUI() {
JFrame frame = new JFrame("DragLabelOnLayeredPane");
frame.getContentPane().add(windowbase);
FoldDrag thedrag=new FoldDrag();
windowbase.add(thedrag);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setPreferredSize(new Dimension(300,300));
frame.pack();
frame.setResizable(true);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
out.active=true;
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
createAndShowUI();
}
});
}
}
編輯:似乎我沒有很好地描述我的手風琴版本。 這是一個鏈接 。
您有特殊的要求,通過使用它的布局管理器可以更好地服務。 這使您能夠控制布局的各個方面,而無需訴諸黑客或“解決方法”,這些工作從未完全奏效或具有奇怪的副作用
public class AccordionLayout implements LayoutManager {
// This "could" be controlled by constraints, but that would assume
// that more then one component could be expanded at a time
private Component expanded;
public void setExpanded(Component expanded) {
this.expanded = expanded;
}
public Component getExpanded() {
return expanded;
}
@Override
public void addLayoutComponent(String name, Component comp) {
}
@Override
public void removeLayoutComponent(Component comp) {
}
@Override
public Dimension preferredLayoutSize(Container parent) {
Dimension size = minimumLayoutSize(parent);
if (expanded != null) {
size.height -= expanded.getMinimumSize().height;
size.height += expanded.getPreferredSize().height;
}
return size;
}
@Override
public Dimension minimumLayoutSize(Container parent) {
int height = 0;
int width = 0;
for (Component comp : parent.getComponents()) {
width = Math.max(width, comp.getPreferredSize().width);
height += comp.getMinimumSize().height;
}
return new Dimension(width, height);
}
@Override
public void layoutContainer(Container parent) {
Insets insets = parent.getInsets();
int availableHeight = parent.getHeight() - (insets.top + insets.bottom);
int x = insets.left;
int y = insets.top;
int maxSize = 0;
Dimension minSize = minimumLayoutSize(parent);
if (expanded != null) {
minSize.height -= expanded.getMinimumSize().height;
// Try an honour the preferred size the expanded component...
maxSize = Math.max(expanded.getPreferredSize().height, availableHeight - minSize.height);
}
int width = parent.getWidth() - (insets.left + insets.right);
for (Component comp : parent.getComponents()) {
if (expanded != comp) {
comp.setSize(width, comp.getMinimumSize().height);
} else {
comp.setSize(width, maxSize);
}
comp.setLocation(x, y);
y += comp.getHeight();
}
}
}
可運行的例子......
這就是enth度,創建一個專門的組件來充當每個“折疊”,但這只是從外部降低了API的復雜性,這意味着,你只需要考慮標題和內容,然后讓剩下的API會照顧好自己
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.FlowLayout;
import java.awt.Insets;
import java.awt.LayoutManager;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.border.LineBorder;
public class Test {
public static void main(String[] args) {
new Test();
}
public Test() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
ex.printStackTrace();
}
JFrame frame = new JFrame("Testing");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private AccordionLayout layout;
public TestPane() {
layout = new AccordionLayout();
setLayout(layout);
AccordionListener listener = new AccordionListener() {
@Override
public void accordionSelected(Component comp) {
layout.setExpanded(comp);
revalidate();
repaint();
}
};
Color colors[] = {Color.RED, Color.BLUE, Color.CYAN, Color.GREEN, Color.MAGENTA, Color.ORANGE, Color.PINK, Color.YELLOW};
String titles[] = {"Red", "Blue", "Cyan", "Green", "Magenta", "Orange", "Pink", "Yellow"};
for (int index = 0; index < colors.length; index++) {
AccordionPanel panel = new AccordionPanel(titles[index], new ContentPane(colors[index]));
panel.setAccordionListener(listener);
add(panel);
}
}
}
public class ContentPane extends JPanel {
public ContentPane(Color background) {
setBackground(background);
}
@Override
public Dimension getPreferredSize() {
return new Dimension(100, 100);
}
}
public interface AccordionListener {
public void accordionSelected(Component comp);
}
public class AccordionPanel extends JPanel {
private JLabel title;
private JPanel header;
private Component content;
private AccordionListener accordionListener;
public AccordionPanel() {
setLayout(new BorderLayout());
title = new JLabel("Title");
header = new JPanel(new FlowLayout(FlowLayout.LEADING));
header.setBackground(Color.GRAY);
header.setBorder(new LineBorder(Color.BLACK));
header.add(title);
add(header, BorderLayout.NORTH);
header.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
AccordionListener listener = getAccordionListener();
if (listener != null) {
listener.accordionSelected(AccordionPanel.this);
}
}
});
}
public AccordionPanel(String title) {
this();
setTitle(title);
}
public AccordionPanel(String title, Component content) {
this(title);
setContentPane(content);
}
public void setAccordionListener(AccordionListener accordionListener) {
this.accordionListener = accordionListener;
}
public AccordionListener getAccordionListener() {
return accordionListener;
}
public void setTitle(String text) {
title.setText(text);
revalidate();
}
public String getText() {
return title.getText();
}
public void setContentPane(Component content) {
if (this.content != null) {
remove(this.content);
}
this.content = content;
if (this.content != null) {
add(this.content);
}
revalidate();
}
public Component getContent() {
return content;
}
@Override
public Dimension getMinimumSize() {
return header.getPreferredSize();
}
@Override
public Dimension getPreferredSize() {
Dimension size = content != null ? content.getPreferredSize() : super.getPreferredSize();
Dimension min = getMinimumSize();
size.width = Math.max(min.width, size.width);
size.height += min.height;
return size;
}
}
public class AccordionLayout implements LayoutManager {
// This "could" be controled by constraints, but that would assume
// that more then one component could be expanded at a time
private Component expanded;
public void setExpanded(Component expanded) {
this.expanded = expanded;
}
public Component getExpanded() {
return expanded;
}
@Override
public void addLayoutComponent(String name, Component comp) {
}
@Override
public void removeLayoutComponent(Component comp) {
}
@Override
public Dimension preferredLayoutSize(Container parent) {
Dimension size = minimumLayoutSize(parent);
if (expanded != null) {
size.height -= expanded.getMinimumSize().height;
size.height += expanded.getPreferredSize().height;
}
return size;
}
@Override
public Dimension minimumLayoutSize(Container parent) {
int height = 0;
int width = 0;
for (Component comp : parent.getComponents()) {
width = Math.max(width, comp.getPreferredSize().width);
height += comp.getMinimumSize().height;
}
return new Dimension(width, height);
}
@Override
public void layoutContainer(Container parent) {
Insets insets = parent.getInsets();
int availableHeight = parent.getHeight() - (insets.top + insets.bottom);
int x = insets.left;
int y = insets.top;
int maxSize = 0;
Dimension minSize = minimumLayoutSize(parent);
if (expanded != null) {
minSize.height -= expanded.getMinimumSize().height;
// Try an honour the preferred size the expanded component...
maxSize = Math.max(expanded.getPreferredSize().height, availableHeight - minSize.height);
}
int width = parent.getWidth() - (insets.left + insets.right);
for (Component comp : parent.getComponents()) {
if (expanded != comp) {
comp.setSize(width, comp.getMinimumSize().height);
} else {
comp.setSize(width, maxSize);
}
comp.setLocation(x, y);
y += comp.getHeight();
}
}
}
}
現在,如果你真的想要挑戰,你可以使用一些動畫布局代理,並做一些像...
最終目標是在添加新面板並且沒有足夠空間時移除舊面板
我猜想在添加一個面板后,你可以將首選高度與實際高度進行比較。 當首選高度較大時,您遇到問題,並根據需要刪除組件。
那么接下來的問題是使用不改變面板高度的布局管理器。 這仍然可以通過GridBagLayout完成。 您只需要覆蓋getMinimumSize()
方法以返回getPreferredSize()
維度。
手風琴的每個部分都可以單獨打開,它們具有任意大小,可以隨時添加
您可能需要考慮使用相對布局 。 您可以添加其首選大小將受到尊重的組件。 因此,您可以檢查首選高度何時大於實際高度。
然后,您還可以添加將根據面板中剩余的空間量調整大小的組件。 這些將是你的擴展面板。
因此,在您的示例中,您展示項目時的示例可以將該組件配置為占用整個可用空間。 如果展開兩個項目,那么每個項目將獲得一半的可用空間。
也許是這樣的:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ExpandingPanel extends JPanel
{
private JPanel expanding;
public ExpandingPanel(String text, Color color)
{
setLayout( new BorderLayout() );
JButton button = new JButton( text );
add(button, BorderLayout.NORTH);
expanding = new JPanel();
expanding.setBackground( color );
expanding.setVisible( false );
add(expanding, BorderLayout.CENTER);
button.addActionListener( new ActionListener()
{
@Override
public void actionPerformed(ActionEvent e)
{
expanding.setVisible( !expanding.isVisible() );
Container parent = ExpandingPanel.this.getParent();
LayoutManager2 layout = (LayoutManager2)parent.getLayout();
if (expanding.isVisible())
layout.addLayoutComponent(ExpandingPanel.this, new Float(1));
else
layout.addLayoutComponent(ExpandingPanel.this, null);
revalidate();
repaint();
}
});
}
private static void createAndShowGUI()
{
RelativeLayout rl = new RelativeLayout(RelativeLayout.Y_AXIS);
rl.setFill( true );
JPanel content = new JPanel( rl );
content.add( new ExpandingPanel("Red", Color.RED) );
content.add( new ExpandingPanel("Blue", Color.BLUE) );
content.add( new ExpandingPanel("Green", Color.GREEN) );
JFrame frame = new JFrame("Expanding Panel");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add( content);
frame.setLocationByPlatform( true );
frame.setSize(200, 300);
frame.setVisible( true );
}
public static void main(String[] args)
{
EventQueue.invokeLater(new Runnable()
{
public void run()
{
createAndShowGUI();
}
});
}
}
當panel.getPreferredSize().height != panel.getHeight()
和panel.getPreferredSize().width != panel.getWidth()
時,你可以告訴某事是“嘎吱嘎吱”的panel.getPreferredSize().height != panel.getHeight()
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