28: Display empty packages.

lizzy-eclipse/lizzy-eclipse-plugin/src/main/java/de/intension/lizzy/plugin/dialogs/PackageBrowserDialog.java

@@ -20,7 +20,6 @@
 import java.util.List;
 
 import org.eclipse.core.resources.IProject;
-import org.eclipse.jdt.core.ICompilationUnit;
 import org.eclipse.jdt.core.IJavaElement;
 import org.eclipse.jdt.core.IJavaProject;
 import org.eclipse.jdt.core.IPackageFragment;
@@ -29,12 +28,18 @@
 import org.eclipse.jdt.core.JavaModelException;
 import org.eclipse.jface.dialogs.Dialog;
 import org.eclipse.swt.SWT;
+import org.eclipse.swt.graphics.GC;
+import org.eclipse.swt.graphics.Image;
 import org.eclipse.swt.layout.GridData;
 import org.eclipse.swt.layout.GridLayout;
-import org.eclipse.swt.widgets.Combo;
 import org.eclipse.swt.widgets.Composite;
 import org.eclipse.swt.widgets.Control;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Label;
+import org.eclipse.swt.widgets.Listener;
 import org.eclipse.swt.widgets.Shell;
+import org.eclipse.swt.widgets.Tree;
+import org.eclipse.swt.widgets.TreeItem;
 
 /**
  * SWT Dialog element to select a package from the selected project.
@@ -44,12 +49,15 @@
 public class PackageBrowserDialog extends Dialog
 {
 
-    private Combo    packages;
+    private Tree             packages;
+    private Label            error;
 
-    private IProject project;
-    private String   path;
+    private IProject         project;
+    private String           path;
 
-    private String   selectedPackage;
+    private String           selectedPackage;
+
+    private static final int IMAGE_MARGIN = 2;
 
     public PackageBrowserDialog(Shell parentShell)
     {
@@ -64,17 +72,69 @@ protected Control createDialogArea(Composite parent)
         layout.marginRight = 5;
         layout.marginLeft = 10;
         container.setLayout(layout);
-        packages = new Combo(container, SWT.READ_ONLY);
-        packages.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false, 1, 1));
+        packages = new Tree(container, SWT.VIRTUAL | SWT.BORDER);
+        packages.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true, 1, 1));
+        packages.addListener(SWT.MeasureItem, measureItemListener());
+        packages.addListener(SWT.PaintItem, paintItemListener());
+        packages.addListener(SWT.Selection, listener -> error.setText(""));
+        error = new Label(container, SWT.NONE);
+        error.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, false, 1, 1));
+        error.setForeground(parent.getDisplay().getSystemColor(SWT.COLOR_RED));
         fillPackageSelection();
         return container;
     }
 
     @Override
     protected void okPressed()
     {
-        selectedPackage = packages.getItem(packages.getSelectionIndex());
-        super.okPressed();
+        TreeItem[] items = packages.getSelection();
+        if (items.length == 1) {
+            TreeItem item = items[0];
+            String text = item.getText();
+            if (item.getData() instanceof Image && text != null) {
+                selectedPackage = text;
+                super.okPressed();
+            }
+        }
+        error.setText("Please select a package!");
+    }
+
+    @Override
+    protected boolean isResizable()
+    {
+        return true;
+    }
+
+    /**
+     * @return {@link SWT#PaintItem} listener for the tree so that the default foreground can be
+     *         augmented.
+     */
+    private Listener paintItemListener()
+    {
+        return event -> {
+            TreeItem item = (TreeItem)event.item;
+            Image trailingImage = (Image)item.getData();
+            if (trailingImage != null) {
+                int itemHeight = packages.getItemHeight();
+                int imageHeight = trailingImage.getBounds().height;
+                int y = event.y + (itemHeight - imageHeight) / 2;
+                event.gc.drawImage(trailingImage, 1, y);
+            }
+        };
+    }
+
+    /**
+     * @return {@link SWT#MeasureItem} listener for the tree so that item sizes can be specified.
+     */
+    private Listener measureItemListener()
+    {
+        return event -> {
+            TreeItem item = (TreeItem)event.item;
+            Image trailingImage = (Image)item.getData();
+            if (trailingImage != null) {
+                event.width += trailingImage.getBounds().width + IMAGE_MARGIN;
+            }
+        };
     }
 
     private void fillPackageSelection()
@@ -84,23 +144,46 @@ private void fillPackageSelection()
         }
         try {
             IJavaProject javaProject = JavaCore.create(project);
-            IPackageFragmentRoot testDir = null;
-            testDir = getPackageRoot(javaProject.getPackageFragmentRoots(), path);
+            IPackageFragmentRoot testDir = getPackageRoot(javaProject.getPackageFragmentRoots(), path);
             if (testDir == null) {
                 return;
             }
             IPackageFragment[] packs = getPackages(testDir.getChildren());
             for (IPackageFragment pack : packs) {
                 String packageName = pack.getElementName();
-                if (packageName != null && !packageName.isEmpty()) {
-                    packages.add(packageName);
+                if (packageName != null) {
+                    TreeItem treePackage = new TreeItem(packages, 0);
+                    treePackage.setText(packageName);
+                    treePackage.setData(getPackageIcon(!pack.containsJavaResources()));
                 }
             }
         } catch (JavaModelException jme) {
             Dialogs.error(jme);
         }
     }
 
+    /**
+     * Get the icon for the package tree.
+     * 
+     * @param isEmpty Defines whether the package is empty or not.
+     * @return Different package icon for empty/non empty package.
+     */
+    private Image getPackageIcon(boolean isEmpty)
+    {
+        String file = "/src/site/resources/images/";
+        if (isEmpty) {
+            file += "package_empty.png";
+        }
+        else {
+            file += "package.png";
+        }
+        Image image = new Image(Display.getDefault(), getClass().getResourceAsStream(file));
+        GC gc = new GC(image);
+        gc.drawImage(image, 16, 16);
+        gc.dispose();
+        return image;
+    }
+
     /**
      * Filters through an array of java elements (folders, packages, etc)
      * and only returns packages, that contain classes.
@@ -113,30 +196,13 @@ private IPackageFragment[] getPackages(IJavaElement[] elements)
     {
         List<IPackageFragment> packageList = new ArrayList<>();
         for (IJavaElement elem : elements) {
-            if (elem instanceof IPackageFragment && hasClasses((IPackageFragment)elem)) {
+            if (elem instanceof IPackageFragment && !((IPackageFragment)elem).hasSubpackages()) {
                 packageList.add((IPackageFragment)elem);
             }
         }
         return packageList.toArray(new IPackageFragment[0]);
     }
 
-    /**
-     * Looks for existing <code>.java</code> classes in the package.
-     * 
-     * @param pack The java package to search.
-     * @return true when existing classes where found.
-     */
-    private boolean hasClasses(IPackageFragment pack)
-        throws JavaModelException
-    {
-        for (IJavaElement elem : pack.getChildren()) {
-            if (elem instanceof ICompilationUnit) {
-                return true;
-            }
-        }
-        return false;
-    }
-
     private IPackageFragmentRoot getPackageRoot(IPackageFragmentRoot[] roots, String path)
     {
         for (IPackageFragmentRoot root : roots) {