adds a first gui integration, see #645

src/main/java/de/neemann/digital/gui/Main.java

@@ -63,6 +63,8 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.swing.*;
+import javax.swing.event.DocumentEvent;
+import javax.swing.event.DocumentListener;
 import javax.swing.filechooser.FileNameExtensionFilter;
 import javax.swing.text.DefaultEditorKit;
 import java.awt.*;
@@ -391,7 +393,7 @@ public final class Main extends JFrame implements ClosingWindowListener.ConfirmS
             if (treeCheckBox.isSelected()) {
                 JSplitPane split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT);
                 treeModel = new LibraryTreeModel(library);
-                split.setLeftComponent(new JScrollPane(new SelectTree(treeModel, circuitComponent, shapeFactory, insertHistory)));
+                split.setLeftComponent(createTreeComponent());
                 split.setRightComponent(circuitScrollPanel);
                 getContentPane().add(split);
                 componentOnPane = split;
@@ -450,6 +452,48 @@ public final class Main extends JFrame implements ClosingWindowListener.ConfirmS
         view.add(viewHelp.createJMenuItem());
     }
 
+    private JComponent createTreeComponent() {
+        JPanel panel = new JPanel(new BorderLayout());
+        JPanel field = new JPanel(new BorderLayout());
+        JTextField textField = new SearchTextField();
+        field.add(textField);
+        JButton clearButton = new JButton(new AbstractAction("\u2717") {
+            @Override
+            public void actionPerformed(ActionEvent actionEvent) {
+                textField.setText("");
+            }
+        });
+        clearButton.setBorder(BorderFactory.createEmptyBorder(2, 5, 2, 5));
+        field.add(clearButton, BorderLayout.EAST);
+        panel.add(field, BorderLayout.NORTH);
+
+        textField.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
+        SelectTree tree = new SelectTree(treeModel, circuitComponent, shapeFactory, insertHistory);
+        textField.getDocument().addDocumentListener(new DocumentListener() {
+            @Override
+            public void insertUpdate(DocumentEvent documentEvent) {
+                changedUpdate(documentEvent);
+            }
+
+            @Override
+            public void removeUpdate(DocumentEvent documentEvent) {
+                changedUpdate(documentEvent);
+            }
+
+            @Override
+            public void changedUpdate(DocumentEvent documentEvent) {
+                String text = textField.getText().trim();
+                if (text.isEmpty())
+                    treeModel = new LibraryTreeModel(library);
+                else
+                    treeModel = new LibraryTreeModel(library, new TextSearchFilter(text));
+                tree.setModel(treeModel);
+            }
+        });
+        panel.add(new JScrollPane(tree));
+        return panel;
+    }
+
     private void clearPane() {
         circuitComponent.setCircuit(new Circuit());
         setFilename(null, true);

src/main/java/de/neemann/digital/gui/SearchTextField.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2021 Helmut Neemann.
+ * Use of this source code is governed by the GPL v3 license
+ * that can be found in the LICENSE file.
+ */
+package de.neemann.digital.gui;
+
+import de.neemann.digital.lang.Lang;
+
+import javax.swing.*;
+import java.awt.*;
+import java.awt.event.FocusEvent;
+import java.awt.event.FocusListener;
+
+/**
+ * JTextField which shows the text "search" if the field is empty.
+ */
+public class SearchTextField extends JTextField {
+
+    /**
+     * Creates a new instance
+     */
+    public SearchTextField() {
+        addFocusListener(new FocusListener() {
+            @Override
+            public void focusGained(FocusEvent e) {
+                repaint();
+            }
+
+            @Override
+            public void focusLost(FocusEvent e) {
+                repaint();
+            }
+        });
+    }
+
+    @Override
+    public void paint(Graphics g) {
+        super.paint(g);
+        if (getText().isEmpty() && !hasFocus()) {
+            g.setColor(Color.GRAY);
+            g.drawString(Lang.get("msg_search"), 5, (getHeight() + getFont().getSize()) / 2);
+        }
+    }
+}

src/main/java/de/neemann/digital/gui/TextSearchFilter.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2021 Helmut Neemann.
+ * Use of this source code is governed by the GPL v3 license
+ * that can be found in the LICENSE file.
+ */
+package de.neemann.digital.gui;
+
+import de.neemann.digital.draw.library.LibraryNode;
+import de.neemann.digital.gui.components.tree.LibraryTreeModel;
+
+/**
+ * Used to filter nodes in the tree view
+ */
+public class TextSearchFilter implements LibraryTreeModel.Filter {
+    private final String filterStr;
+
+    /**
+     * Creates a new filter
+     *
+     * @param filterStr the search string
+     */
+    public TextSearchFilter(String filterStr) {
+        this.filterStr = filterStr.toLowerCase();
+    }
+
+    @Override
+    public boolean accept(LibraryNode node) {
+        return node.getName().toLowerCase().contains(filterStr)
+                || node.getTranslatedName().toLowerCase().contains(filterStr);
+    }
+}

src/main/java/de/neemann/digital/gui/components/tree/LibraryTreeModel.java

@@ -111,6 +111,13 @@ public class LibraryTreeModel implements TreeModel, LibraryListener {
         }
     }
 
+    /**
+     * @return true if this model is filtered
+     */
+    public boolean isFiltered() {
+        return filter != null;
+    }
+
     private Container getContainer(LibraryNode libraryNode) {
         Container c = map.get(libraryNode);
         if (c == null) {

src/main/java/de/neemann/digital/gui/components/tree/SelectTree.java

@@ -22,6 +22,7 @@ import java.awt.*;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
 import java.io.IOException;
+import java.util.Enumeration;
 
 /**
  * Tree to select items
@@ -29,6 +30,7 @@ import java.io.IOException;
 public class SelectTree extends JTree {
 
     private final ShapeFactory shapeFactory;
+    private Enumeration<TreePath> storedExpanded;
 
     /**
      * Create a new instance
@@ -68,6 +70,27 @@ public class SelectTree extends JTree {
         expandPath(new TreePath(model.getFirstLeafParent().getPath()));
     }
 
+    /**
+     * Sets a new model to this SelectTree.
+     *
+     * @param newModel the new model
+     */
+    public void setModel(LibraryTreeModel newModel) {
+        LibraryTreeModel oldModel = (LibraryTreeModel) getModel();
+        if (!oldModel.isFiltered() && newModel.isFiltered())
+            storedExpanded = getExpandedDescendants(new TreePath(getModel().getRoot()));
+
+        boolean restore = oldModel.isFiltered() && !newModel.isFiltered();
+
+        super.setModel(newModel);
+        if (restore && storedExpanded != null) {
+            while (storedExpanded.hasMoreElements())
+                expandPath(storedExpanded.nextElement());
+            storedExpanded = null;
+        } else
+            expandPath(new TreePath(newModel.getFirstLeafParent().getPath()));
+    }
+
     @Override
     public String getToolTipText(MouseEvent e) {
         TreePath selPath = getPathForLocation(e.getX(), e.getY());

src/main/resources/lang/lang_de.xml

@@ -51,7 +51,7 @@
     <string name="elem_Help_inputs">Eingänge</string>
     <string name="elem_Help_outputs">Ausgänge</string>
     <string name="elem_Help_attributes">Veränderbare Attribute</string>
-
+    <string name="msg_search">Suche</string>
 
     <!-- logik -->
 

src/main/resources/lang/lang_en.xml

@@ -51,6 +51,7 @@
     <string name="elem_Help_inputs">Inputs</string>
     <string name="elem_Help_outputs">Outputs</string>
     <string name="elem_Help_attributes">Attributes</string>
+    <string name="msg_search">search</string>
 
 
     <!-- logic -->