Implement filter-based table viewer via the new FilterTable class

This moves the viewer-agnostic components of the FilterTree widget into
an abstract base class, which is then used to implement the FilterTable
widget.

bundles/org.eclipse.ui.workbench/META-INF/MANIFEST.MF

@@ -2,7 +2,7 @@ Manifest-Version: 1.0
 Bundle-ManifestVersion: 2
 Bundle-Name: %pluginName
 Bundle-SymbolicName: org.eclipse.ui.workbench; singleton:=true
-Bundle-Version: 3.134.100.qualifier
+Bundle-Version: 3.135.0.qualifier
 Bundle-Activator: org.eclipse.ui.internal.WorkbenchPlugin
 Bundle-ActivationPolicy: lazy
 Bundle-Vendor: %providerName

bundles/org.eclipse.ui.workbench/eclipseui/org/eclipse/ui/dialogs/AbstractFilteredViewer.java

@@ -0,0 +1,373 @@
+/*******************************************************************************
+ * Copyright (c) 2024 Patrick Ziegler and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     Patrick Ziegler - initial API and implementation
+ ******************************************************************************/
+package org.eclipse.ui.dialogs;
+
+import org.eclipse.core.runtime.jobs.Job;
+import org.eclipse.jface.viewers.ColumnViewer;
+import org.eclipse.swt.SWT;
+import org.eclipse.swt.events.FocusAdapter;
+import org.eclipse.swt.events.FocusEvent;
+import org.eclipse.swt.events.MouseAdapter;
+import org.eclipse.swt.events.MouseEvent;
+import org.eclipse.swt.layout.GridData;
+import org.eclipse.swt.layout.GridLayout;
+import org.eclipse.swt.widgets.Composite;
+import org.eclipse.swt.widgets.Display;
+import org.eclipse.swt.widgets.Text;
+import org.eclipse.ui.IWorkbenchPreferenceConstants;
+import org.eclipse.ui.PlatformUI;
+import org.eclipse.ui.internal.WorkbenchMessages;
+import org.eclipse.ui.progress.WorkbenchJob;
+
+/**
+ * The abstract base class for a composite containing both a column viewer and a
+ * text widget. The text drives the filter of the viewer. Current
+ * implementations support both table- and tree-based viewers.
+ *
+ * @since 3.135
+ */
+public abstract sealed class AbstractFilteredViewer extends Composite permits FilteredTable, FilteredTree {
+
+	/**
+	 * The filter text widget to be used by this tree. This value may be
+	 * <code>null</code> if there is no filter widget, or if the controls have not
+	 * yet been created.
+	 */
+	protected Text filterText;
+
+	/**
+	 * The Composite on which the filter controls are created. This is used to set
+	 * the background color of the filter controls to match the surrounding
+	 * controls.
+	 */
+	protected Composite filterComposite;
+
+	/**
+	 * The text to initially show in the filter text control.
+	 */
+	protected String initialText = ""; //$NON-NLS-1$
+
+	/**
+	 * The job used to refresh the tree.
+	 */
+	private Job refreshJob;
+
+	/**
+	 * The parent composite of the filtered tree.
+	 */
+	protected Composite parent;
+
+	/**
+	 * Whether or not to show the filter controls (text and clear button). The
+	 * default is to show these controls. This can be overridden by providing a
+	 * setting in the product configuration file. The setting to add to not show
+	 * these controls is:
+	 *
+	 * org.eclipse.ui/SHOW_FILTERED_TEXTS=false
+	 */
+	protected boolean showFilterControls;
+
+	/**
+	 * Tells whether this filtered tree is used to make quick selections. In this
+	 * mode the first match in the tree is automatically selected while filtering
+	 * and the 'Enter' key is not used to move the focus to the tree.
+	 */
+	private boolean quickSelectionMode = false;
+
+	/**
+	 * Time for refresh job delay in terms of expansion in long value
+	 */
+	private final long refreshJobDelayInMillis;
+
+	protected AbstractFilteredViewer(Composite parent, int style, long refreshJobDelayInMillis) {
+		super(parent, style);
+		this.parent = parent;
+		this.refreshJobDelayInMillis = refreshJobDelayInMillis;
+	}
+
+	/**
+	 * Create the viewer.
+	 *
+	 * @param style the style bits for the {@code viewer}.
+	 */
+	protected final void init(int style) {
+		showFilterControls = PlatformUI.getPreferenceStore()
+				.getBoolean(IWorkbenchPreferenceConstants.SHOW_FILTERED_TEXTS);
+		createControl(parent, style);
+		createRefreshJob();
+		setInitialText(WorkbenchMessages.FilteredTree_FilterMessage);
+		setFont(parent.getFont());
+		getViewer().getControl().addDisposeListener(e -> refreshJob.cancel());
+	}
+
+	/**
+	 * Create the filtered tree's controls. Subclasses should override.
+	 *
+	 * @param parent    the parent
+	 * @param treeStyle SWT style bits used to create the tree
+	 */
+	protected void createControl(Composite parent, int treeStyle) {
+		GridLayout layout = new GridLayout();
+		layout.marginHeight = 0;
+		layout.marginWidth = 0;
+		setLayout(layout);
+
+		if (parent.getLayout() instanceof GridLayout) {
+			setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
+		}
+
+		if (showFilterControls) {
+			filterComposite = new Composite(this, SWT.NONE);
+			GridLayout filterLayout = new GridLayout();
+			filterLayout.marginHeight = 0;
+			filterLayout.marginWidth = 0;
+			filterComposite.setLayout(filterLayout);
+			filterComposite.setFont(parent.getFont());
+
+			createFilterControls(filterComposite);
+			filterComposite.setLayoutData(new GridData(SWT.FILL, SWT.BEGINNING, true, false));
+		}
+	}
+
+	/**
+	 * Create the filter controls. By default, a text and corresponding tool bar
+	 * button that clears the contents of the text is created. Subclasses may
+	 * override.
+	 *
+	 * @param parent parent <code>Composite</code> of the filter controls
+	 * @return the <code>Composite</code> that contains the filter controls
+	 */
+	protected Composite createFilterControls(Composite parent) {
+		createFilterText(parent);
+		return parent;
+	}
+
+	/**
+	 * Create the refresh job for the receiver.
+	 */
+	private void createRefreshJob() {
+		refreshJob = doCreateRefreshJob();
+		refreshJob.setSystem(true);
+	}
+
+	/**
+	 * Creates a workbench job that will refresh the tree based on the current
+	 * filter text. Subclasses may override.
+	 *
+	 * @return a workbench job that can be scheduled to refresh the tree
+	 */
+	protected abstract WorkbenchJob doCreateRefreshJob();
+
+	/**
+	 * Creates the filter text and adds listeners. This method calls
+	 * {@link #doCreateFilterText(Composite)} to create the text control. Subclasses
+	 * should override {@link #doCreateFilterText(Composite)} instead of overriding
+	 * this method.
+	 *
+	 * @param parent <code>Composite</code> of the filter text
+	 */
+	protected void createFilterText(Composite parent) {
+		filterText = doCreateFilterText(parent);
+
+		filterText.addFocusListener(new FocusAdapter() {
+			@Override
+			public void focusGained(FocusEvent e) {
+				/*
+				 * Running in an asyncExec because the selectAll() does not appear to work when
+				 * using mouse to give focus to text.
+				 */
+				Display display = filterText.getDisplay();
+				display.asyncExec(() -> {
+					if (!filterText.isDisposed()) {
+						if (getInitialText().equals(filterText.getText().trim())) {
+							filterText.selectAll();
+						}
+					}
+				});
+			}
+
+			@Override
+			public void focusLost(FocusEvent e) {
+				if (filterText.getText().equals(initialText)) {
+					setFilterText(""); //$NON-NLS-1$
+					textChanged();
+				}
+			}
+		});
+
+		filterText.addMouseListener(new MouseAdapter() {
+			@Override
+			public void mouseDown(MouseEvent e) {
+				if (filterText.getText().equals(initialText)) {
+					// XXX: We cannot call clearText() due to
+					// https://bugs.eclipse.org/bugs/show_bug.cgi?id=260664
+					setFilterText(""); //$NON-NLS-1$
+					textChanged();
+				}
+			}
+		});
+
+		filterText.addModifyListener(e -> textChanged());
+
+		GridData gridData = new GridData(SWT.FILL, SWT.CENTER, true, false);
+		filterText.setLayoutData(gridData);
+	}
+
+	/**
+	 * Creates the text control for entering the filter text. Subclasses may
+	 * override.
+	 *
+	 * @param parent the parent composite
+	 * @return the text widget
+	 */
+	protected Text doCreateFilterText(Composite parent) {
+		return new Text(parent, SWT.SINGLE | SWT.BORDER | SWT.SEARCH | SWT.ICON_CANCEL);
+	}
+
+	/**
+	 * Update the receiver after the text has changed.
+	 */
+	protected void textChanged() {
+		// cancel currently running job first, to prevent unnecessary redraw
+		refreshJob.cancel();
+		refreshJob.schedule(getRefreshJobDelay());
+	}
+
+	/**
+	 * Return the time delay that should be used when scheduling the filter refresh
+	 * job. Subclasses may override.
+	 *
+	 * @return a time delay in milliseconds before the job should run
+	 */
+	protected long getRefreshJobDelay() {
+		return refreshJobDelayInMillis;
+	}
+
+	/**
+	 * Clears the text in the filter text widget.
+	 */
+	protected void clearText() {
+		setFilterText(""); //$NON-NLS-1$
+		textChanged();
+	}
+
+	/**
+	 * Set the text in the filter control.
+	 *
+	 * @param filterText the text to set.
+	 */
+	protected void setFilterText(String filterText) {
+		if (this.filterText != null) {
+			this.filterText.setText(filterText);
+			selectAll();
+		}
+	}
+
+	/**
+	 * Get the column viewer of the receiver.
+	 *
+	 * @return the column viewer
+	 */
+	public abstract ColumnViewer getViewer();
+
+	/**
+	 * Get the filter text for the receiver, if it was created. Otherwise return
+	 * <code>null</code>.
+	 *
+	 * @return the filter Text, or null if it was not created
+	 */
+	public Text getFilterControl() {
+		return filterText;
+	}
+
+	/**
+	 * Convenience method to return the text of the filter control. If the text
+	 * widget is not created, then null is returned.
+	 *
+	 * @return String in the text, or null if the text does not exist
+	 */
+	protected String getFilterString() {
+		return filterText != null ? filterText.getText() : null;
+	}
+
+	/**
+	 * Set the text that will be shown until the first focus. A default value is
+	 * provided, so this method only need be called if overriding the default
+	 * initial text is desired.
+	 *
+	 * @param text initial text to appear in text field
+	 */
+	public void setInitialText(String text) {
+		initialText = text;
+		if (filterText != null) {
+			filterText.setMessage(text);
+			if (filterText.isFocusControl()) {
+				setFilterText(initialText);
+				textChanged();
+			} else {
+				getDisplay().asyncExec(() -> {
+					if (!filterText.isDisposed() && filterText.isFocusControl()) {
+						setFilterText(initialText);
+						textChanged();
+					}
+				});
+			}
+		} else {
+			setFilterText(initialText);
+			textChanged();
+		}
+	}
+
+	/**
+	 * Sets whether this filtered tree is used to make quick selections. In this
+	 * mode the first match in the tree is automatically selected while filtering
+	 * and the 'Enter' key is not used to move the focus to the tree.
+	 * <p>
+	 * By default, this is set to <code>false</code>.
+	 * </p>
+	 *
+	 * @param enabled <code>true</code> if this filtered tree is used to make quick
+	 *                selections, <code>false</code> otherwise
+	 */
+	public void setQuickSelectionMode(boolean enabled) {
+		this.quickSelectionMode = enabled;
+	}
+
+	/**
+	 * Select all text in the filter text field.
+	 */
+	protected void selectAll() {
+		if (filterText != null) {
+			filterText.selectAll();
+		}
+	}
+
+	/**
+	 * Get the initial text for the receiver.
+	 *
+	 * @return String
+	 */
+	protected String getInitialText() {
+		return initialText;
+	}
+
+	/**
+	 * Get the quick selection mode.
+	 *
+	 * @return {@code true}, if enabled.
+	 */
+	protected boolean isQuickSelectionMode() {
+		return quickSelectionMode;
+	}
+}