Java JTree条目渲染问题
在我的项目GUI中,我使用Java JTree条目渲染问题,java,swing,jtree,Java,Swing,Jtree,在我的项目GUI中,我使用JTree来显示文件系统,我遇到了一个特定于渲染的问题:所述JTree中的某些条目似乎能够正确渲染,也能够在先前选择的条目上渲染自己。这很难解释,所以我认为包括一个截图是最容易理解的 为了实现这一点,我用箭头键从上到下快速移动 我不太清楚这个问题的来源,但我怀疑这可能是我的TreeModel或CellRenderer的问题,这两个都包含在下面 欢迎任何可以帮助我解决此问题的帮助 import java.awt.Component; import java.awt.im
JTree
来显示文件系统,我遇到了一个特定于渲染的问题:所述JTree
中的某些条目似乎能够正确渲染,也能够在先前选择的条目上渲染自己。这很难解释,所以我认为包括一个截图是最容易理解的
为了实现这一点,我用箭头键从上到下快速移动
我不太清楚这个问题的来源,但我怀疑这可能是我的TreeModel
或CellRenderer
的问题,这两个都包含在下面
欢迎任何可以帮助我解决此问题的帮助
import java.awt.Component;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Vector;
import javax.imageio.ImageIO;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.WindowConstants;
import javax.swing.event.TreeModelListener;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.TreeModel;
import javax.swing.tree.TreePath;
public class MCVE {
public static void main(String[] args) throws Throwable {
JFrame frame = new JFrame();
frame.getContentPane().add(new FileSystemTree(new File(System.getProperty("user.home"))));
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
}
class FileSystemTree extends JPanel {
private File root;
private FileSystemTreeModel model;
private final JTree fileSystem;
public FileSystemTree(File root) throws IOException {
this.root = root;
model = new FileSystemTreeModel(root);
fileSystem = new JTree(model);
fileSystem.setEditable(false);
fileSystem.setCellRenderer(new FileSystemTreeCellRenderer());
fileSystem.putClientProperty("JTree.lineStyle", "None");
add(new JScrollPane(fileSystem));
}
}
class FileSystemTreeCellRenderer extends DefaultTreeCellRenderer {
private final Icon folderSpecial;
private final Icon folderOther;
private final Icon fileSpecial;
private final Icon fileOther;
public FileSystemTreeCellRenderer() throws IOException {
InputStream stream;
BufferedImage image;
stream = new FileInputStream("folder-special.png");
image = ImageIO.read(stream);
folderSpecial = new ImageIcon(image);
stream.close();
stream = new FileInputStream("folder-other.png");
image = ImageIO.read(stream);
folderOther = new ImageIcon(image);
stream.close();
stream = new FileInputStream("file-special.png");
image = ImageIO.read(stream);
fileSpecial = new ImageIcon(image);
stream.close();
stream = new FileInputStream("file-other.png");
image = ImageIO.read(stream);
fileOther = new ImageIcon(image);
stream.close();
}
@Override
public Component getTreeCellRendererComponent(JTree tree, Object value, boolean sel, boolean expanded, boolean leaf, int row, boolean hasFocus) {
super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf, row, hasFocus);
if (value instanceof File) {
Icon icon = null;
File file = (File) value;
if (file.isDirectory()) {
if (file.getName().endsWith("-special")) {
icon = folderSpecial;
} else {
icon = folderOther;
}
} else if (file.isFile()) {
if (file.getName().endsWith(".special")) {
icon = fileSpecial;
} else {
icon = fileOther;
}
}
setIcon(icon);
}
return this;
}
}
class FileSystemTreeModel implements TreeModel, Comparator<File> {
private final File root;
private final Vector<TreeModelListener> listeners = new Vector<>();
public FileSystemTreeModel(File root) {
if (!root.isDirectory()) throw new IllegalArgumentException();
this.root = root;
}
@Override
public int compare(File a, File b) {
if (a.isDirectory() && !b.isDirectory()) return -1;
if (!a.isDirectory() && b.isDirectory()) return 1;
return a.getName().compareToIgnoreCase(b.getName());
}
@Override
public File getRoot() {
return root;
}
@Override
public File getChild(Object parent, int index) {
File dir = (File) parent;
File[] files = dir.listFiles();
String[] children = new String[files.length];
Arrays.sort(files, this::compare);
for (int i = 0; i < files.length; i++) {
children[i] = files[i].getName();
}
return new TreeFile(dir, children[index]);
}
@Override
public int getChildCount(Object parent) {
File file = (File) parent;
if (file.isDirectory()) {
String[] fileList = file.list();
if (fileList != null) return fileList.length;
}
return 0;
}
@Override
public boolean isLeaf(Object node) {
File file = (File) node;
return file.isFile();
}
@Override
public int getIndexOfChild(Object parent, Object child) {
File dir = (File) parent;
File file = (File) child;
File[] children = dir.listFiles();
Arrays.sort(children, this::compare);
for (int i = 0; i < children.length; i++) {
if (file.equals(children[i])) return i;
}
return -1;
}
@Override
public void valueForPathChanged(TreePath path, Object value) {}
@Override
public void addTreeModelListener(TreeModelListener listener) {
listeners.add(listener);
}
@Override
public void removeTreeModelListener(TreeModelListener listener) {
listeners.remove(listener);
}
private static class TreeFile extends File {
public TreeFile(File parent, String path) {
super(parent, path);
}
@Override
public String toString() {
return getName();
}
}
}
导入java.awt.Component;
导入java.awt.image.buffereImage;
导入java.io.File;
导入java.io.FileInputStream;
导入java.io.IOException;
导入java.io.InputStream;
导入java.util.array;
导入java.util.Comparator;
导入java.util.Vector;
导入javax.imageio.imageio;
导入javax.swing.Icon;
导入javax.swing.ImageIcon;
导入javax.swing.JFrame;
导入javax.swing.JPanel;
导入javax.swing.JScrollPane;
导入javax.swing.JTree;
导入javax.swing.WindowConstants;
导入javax.swing.event.TreeModelListener;
导入javax.swing.tree.DefaultTreeCellRenderer;
导入javax.swing.tree.TreeModel;
导入javax.swing.tree.TreePath;
公共级MCVE{
公共静态void main(字符串[]args)抛出可丢弃的{
JFrame=新JFrame();
frame.getContentPane().add(新文件系统树(新文件(System.getProperty(“user.home”)));
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.pack();
frame.setVisible(true);
}
}
类FileSystemTree扩展了JPanel{
私有文件根;
私有文件系统树模型;
私有最终JTree文件系统;
公共文件系统树(文件根目录)引发IOException{
this.root=根;
模型=新文件系统树模型(根);
文件系统=新的JTree(模型);
fileSystem.setEditable(false);
setCellRenderer(新的FileSystemTreeCellRenderer());
putClientProperty(“JTree.lineStyle”,“无”);
添加(新的JScrollPane(文件系统));
}
}
类FileSystemTreeCellRenderer扩展了DefaultTreeCellRenderer{
私人最终图标folderSpecial;
私人最终图标folderOther;
私有最终图标文件专用;
私人最终图标文件其他;
公共文件系统TreeCellRenderer()引发IOException{
输入流;
缓冲图像;
stream=newfileinputstream(“folder special.png”);
image=ImageIO.read(流);
folderSpecial=新图像图标(图像);
stream.close();
stream=newfileinputstream(“folder other.png”);
image=ImageIO.read(流);
folderOther=新图像图标(图像);
stream.close();
stream=newfileinputstream(“file special.png”);
image=ImageIO.read(流);
fileSpecial=新图像图标(图像);
stream.close();
stream=newfileinputstream(“file other.png”);
image=ImageIO.read(流);
fileOther=新图像图标(图像);
stream.close();
}
@凌驾
公共组件GetTreeCellRenderComponent(JTree树、对象值、布尔sel、布尔扩展、布尔叶、int行、布尔hasFocus){
super.gettreeCellrenderComponent(树、值、sel、展开、叶、行、hasFocus);
if(文件实例的值){
图标=空;
文件=(文件)值;
if(file.isDirectory()){
if(file.getName().endsWith(“-special”)){
icon=folderSpecial;
}否则{
图标=折叠其他;
}
}else if(file.isFile()){
if(file.getName().endsWith(“.special”)){
图标=文件专用;
}否则{
icon=fileOther;
}
}
设置图标(图标);
}
归还这个;
}
}
类FileSystemTreeModel实现TreeModel、Comparator{
私有最终文件根;
私有最终向量侦听器=新向量();
公共文件系统树模型(文件根){
如果(!root.isDirectory())抛出新的IllegalArgumentException();
this.root=根;
}
@凌驾
公共整数比较(文件a、文件b){
if(a.isDirectory()&&!b.isDirectory())返回-1;
如果(!a.isDirectory()&&b.isDirectory())返回1;
返回a.getName().compareToIgnoreCase(b.getName());
}
@凌驾
公共文件getRoot(){
返回根;
}
@凌驾
公共文件getChild(对象父对象,int索引){
文件目录=(文件)父级;
File[]files=dir.listFiles();
String[]children=新字符串[files.length];
sort(文件,this::compare);
对于(int i=0;ipublic class FileSystemTreeCellRenderer implements TreeCellRenderer {
protected Color foregroundColor = null;
protected Color backgroundColor = null;
protected Color selectionForegroundColor = null;
protected Color selectionBackgroundColor = null;
protected Map<Object, JLabel> labels = new HashMap<>();
protected final Icon folderSpecial;
protected final Icon folderOther;
protected final Icon fileSpecial;
protected final Icon fileOther;
public FileSystemTreeCellRenderer() throws IOException {
InputStream stream;
BufferedImage image;
stream = new FileInputStream("folder-special.png");
image = ImageIO.read(stream);
folderSpecial = new ImageIcon(image);
stream.close();
stream = new FileInputStream("folder-other.png");
image = ImageIO.read(stream);
folderOther = new ImageIcon(image);
stream.close();
stream = new FileInputStream("file-special.png");
image = ImageIO.read(stream);
fileSpecial = new ImageIcon(image);
stream.close();
stream = new FileInputStream("file-other.png");
image = ImageIO.read(stream);
fileOther = new ImageIcon(image);
stream.close();
}
protected JLabel getLabelFor(Object object) {
JLabel label = labels.get(object);
if(label == null) {
label = new JLabel();
labels.put(object, label);
}
return label;
}
public Color getForegroundColor() {
if (foregroundColor == null) return UIManager.getColor("Tree.textForeground");
return foregroundColor;
}
public Color getBackgroundColor() {
if (backgroundColor == null) return UIManager.getColor("Tree.textBackground");
return backgroundColor;
}
public Color getSelectionForegroundColor() {
if (selectionForegroundColor == null) return UIManager.getColor("Tree.selectionForeground");
return selectionForegroundColor;
}
public Color getSelectionBackgroundColor() {
if (selectionBackgroundColor == null) return UIManager.getColor("Tree.selectionBackground");
return selectionBackgroundColor;
}
@Override
public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected, boolean expanded, boolean leaf, int row, boolean hasFocus) {
JLabel label = getLabelFor(value);
label.setText(Objects.toString(value, ""));
label.setOpaque(true);
label.setBackground(selected ? getSelectionBackgroundColor() : getBackgroundColor());
label.setForeground(selected ? getSelectionForegroundColor() : getForegroundColor());
label.setEnabled(tree.isEnabled());
label.setComponentOrientation(tree.getComponentOrientation());
if (value instanceof File) {
Icon icon = null;
File file = (File) value;
if (file.isDirectory()) {
if (file.getName().endsWith("-special")) {
icon = folderSpecial;
} else {
icon = folderOther;
}
} else if (file.isFile()) {
if (file.getName().endsWith(".special")) {
icon = fileSpecial;
} else {
icon = fileOther;
}
}
label.setIcon(icon);
}
return label;
}
}