Attachment 147094 Details for Bug 289341 – Hyper links in tables or trees

Hyper links in tables or trees

TreeViewerLinkColumnSnippet.java (text/plain), 16.80 KB, created by Daniel Krügler

on 2009-09-14 08:16:19 EDT

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Creator: Daniel Krügler

Created: 2009-09-14 08:16:19 EDT

Size: 16.80 KB

patch

obsolete

>/**
> * Copyright (c) 2009 Daniel Kruegler and others.
> * All rights reserved. This program and the accompanying materials
> * are made available under the terms of the Eclipse Public License v1.0
> * which accompanies this distribution, and is available at
> * http://www.eclipse.org/legal/epl-v10.html
> *
> * Contributors:
> * Daniel Kruegler - initial API and implementation
> */
>package org.eclipse.jface.snippets.viewers;
>
>import org.eclipse.jface.dialogs.MessageDialog;
>import org.eclipse.jface.resource.JFaceColors;
>import org.eclipse.jface.viewers.ColumnLabelProvider;
>import org.eclipse.jface.viewers.ColumnViewer;
>import org.eclipse.jface.viewers.ITreeContentProvider;
>import org.eclipse.jface.viewers.StyledCellLabelProvider;
>import org.eclipse.jface.viewers.StyledString;
>import org.eclipse.jface.viewers.TreeViewer;
>import org.eclipse.jface.viewers.TreeViewerColumn;
>import org.eclipse.jface.viewers.Viewer;
>import org.eclipse.jface.viewers.ViewerCell;
>import org.eclipse.jface.viewers.ViewerColumn;
>import org.eclipse.jface.viewers.StyledString.Styler;
>import org.eclipse.swt.SWT;
>import org.eclipse.swt.events.MouseAdapter;
>import org.eclipse.swt.events.MouseEvent;
>import org.eclipse.swt.events.MouseListener;
>import org.eclipse.swt.events.MouseMoveListener;
>import org.eclipse.swt.events.MouseTrackListener;
>import org.eclipse.swt.graphics.Color;
>import org.eclipse.swt.graphics.Cursor;
>import org.eclipse.swt.graphics.Point;
>import org.eclipse.swt.graphics.TextStyle;
>import org.eclipse.swt.layout.GridData;
>import org.eclipse.swt.layout.GridLayout;
>import org.eclipse.swt.widgets.Control;
>import org.eclipse.swt.widgets.Display;
>import org.eclipse.swt.widgets.Shell;
>import org.eclipse.swt.widgets.Tree;
>
>/**
> * Demonstrate usage of {@link HyperlinkColumnLabelProvider}.
> * 
> * @author Daniel Kruegler
> * @since 3.4.2
> */
>public class TreeViewerLinkColumnSnippet {
>
>	public TreeViewerLinkColumnSnippet(final Shell shell) {
>		final TreeViewer v = new TreeViewer(shell, SWT.BORDER
>				| SWT.FULL_SELECTION);
>		Tree tree = v.getTree();
>
>		GridData data = new GridData(SWT.FILL, SWT.FILL, true, true);
>		data.heightHint = 250;
>
>		tree.setLayoutData(data);
>		tree.setLinesVisible(true);
>		tree.setHeaderVisible(true);
>
>		TreeViewerColumn column = new TreeViewerColumn(v, SWT.NONE);
>		column.getColumn().setWidth(200);
>		column.getColumn().setMoveable(true);
>		column.getColumn().setText("People");
>		column.setLabelProvider(new ColumnLabelProvider() {
>
>			public String getText(Object element) {
>				if (element instanceof Person) {
>					Person datum = (Person) element;
>					return datum.name;
>				} else {
>					Project datum = (Project) element;
>					return datum.name;
>				}
>			}
>
>		});
>
>		column = new TreeViewerColumn(v, SWT.NONE);
>		column.getColumn().setWidth(200);
>		column.getColumn().setMoveable(true);
>		column.getColumn().setText("E-mail");
>		column.setLabelProvider(new HyperlinkColumnLabelProvider() {
>
>			protected String getLinkText(Object element) {
>				if (element instanceof Person) {
>					Person datum = (Person) element;
>					return datum.email;
>				} else {
>					return null;
>				}
>			}
>
>			protected void linkActivated(Object element) {
>				MessageDialog.openInformation(getViewer().getControl()
>						.getShell(), null, "Selected element: " + element);
>			}
>
>		});
>
>		column = new TreeViewerColumn(v, SWT.NONE);
>		column.getColumn().setWidth(100);
>		column.getColumn().setMoveable(true);
>		column.getColumn().setText("Age");
>		column.setLabelProvider(new ColumnLabelProvider() {
>
>			public String getText(Object element) {
>				if (element instanceof Person) {
>					Person datum = (Person) element;
>					return String.valueOf(datum.age);
>				} else {
>					return null;
>				}
>			}
>
>		});
>
>		v.setContentProvider(new MyContentProvider());
>		v.setInput(createModel());
>	}
>
>	private static class Person {
>		String name;
>		String email;
>		int age;
>	}
>
>	private static class Project {
>		String name;
>		Person[] people;
>	}
>
>	private static Project[] createModel() {
>		Project[] result = new Project[2];
>		Person[] persons;
>		{
>			Project item = new Project();
>			item.name = "Project Pizza";
>			persons = new Person[2];
>			Person p1 = new Person();
>			p1.name = "Jane";
>			p1.age = 24;
>			p1.email = "jane@different";
>			persons[0] = p1;
>			Person p2 = new Person();
>			p2.name = "Bill";
>			p2.age = 53;
>			p2.email = "bill.sunshine@northpole";
>			persons[1] = p2;
>			item.people = persons;
>			result[0] = item;
>		}
>		{
>			Project item = new Project();
>			item.name = "Project Ice Cream";
>			persons = new Person[2];
>			Person p1 = new Person();
>			p1.name = "Herb";
>			p1.age = 12;
>			p1.email = "hb@santaclaus";
>			persons[0] = p1;
>			Person p2 = new Person();
>			p2.name = "Susan";
>			p2.age = 33;
>			p2.email = "susan.withness@something";
>			persons[1] = p2;
>			item.people = persons;
>			result[1] = item;
>		}
>		return result;
>	}
>
>	public static void main(String[] args) {
>		Display display = new Display();
>		Shell shell = new Shell(display);
>		shell.setLayout(new GridLayout(1, false));
>		GridData data = new GridData(SWT.FILL, SWT.FILL, true, true);
>		shell.setLayoutData(data);
>		new TreeViewerLinkColumnSnippet(shell);
>
>		shell.pack();
>		shell.open();
>
>		while (!shell.isDisposed()) {
>			if (!display.readAndDispatch())
>				display.sleep();
>		}
>
>		display.dispose();
>	}
>
>	private static class MyContentProvider implements ITreeContentProvider {
>
>		public Object[] getElements(Object inputElement) {
>			return ((Object[]) inputElement);
>		}
>
>		public void dispose() {
>		}
>
>		public void inputChanged(Viewer viewer, Object oldInput, Object newInput) {
>		}
>
>		public Object[] getChildren(Object parentElement) {
>			if (parentElement instanceof Project)
>				return ((Project) parentElement).people;
>			else
>				return getElements(parentElement);
>		}
>
>		public Object getParent(Object element) {
>			return null;
>		}
>
>		public boolean hasChildren(Object element) {
>			if (element instanceof Person)
>				return false;
>			Project result = (Project) element;
>			return result.people.length > 1;
>		}
>
>	}
>
>}
>
>/**
> * A specialized {@link org.eclipse.jface.viewers.CellLabelProvider}, which
> * simulates the look-and-feel and the behavior of a normal hyper-link. The link
> * behavior may be optional for some cells, therefore subclasses have to
> * implement {@link #getLinkText(Object)}, which has to return a non
> * <code>null</code> value for any link cell, or {@code null} otherwise. In
> * addition to the adaption of the mouse cursor, link activation behavior has to
> * be implemented by overriding {@link #linkActivated(Object)}.
> * 
> * This label provider implementation contains column-specific state, therefore
> * it cannot be used as a single label provider for a
> * {@link ColumnViewer}.
> * 
> * @author Daniel Kruegler
> */
>abstract class HyperlinkColumnLabelProvider extends StyledCellLabelProvider {
>
>	/**
>	 * Convenience short-cuts for typical link colors (Could be a Java 1.5
>	 * enum).
>	 * 
>	 * @see HyperlinkColumnLabelProvider#linkColor(Display)
>	 */
>	public static final class LinkColor {
>
>		private LinkColor() {
>		}
>
>		/**
>		 * The standard hyper-link color
>		 */
>		public static final LinkColor Normal = new LinkColor();
>		/**
>		 * The color for active hyper-links
>		 */
>		public static final LinkColor Active = new LinkColor();
>		/**
>		 * The color {@link SWT#COLOR_BLUE}
>		 */
>		public static final LinkColor Blue = new LinkColor();
>
>	};
>
>	private Control viewerCtrl;
>
>	private Color linkColor;
>
>	private Styler styler;
>
>	private Cursor linkCursor;
>
>	private Cursor busyCursor;
>
>	/**
>	 * Internal state variable for mouse movements that specifies whether the
>	 * current mouse cursor shows the typical hand.
>	 */
>	private boolean linkEntered;
>
>	/**
>	 * Lazy evaluation of the actual column index of this label provider. During
>	 * the first invocation of {@link #update(ViewerCell)} the proper column
>	 * index will be determined and set. This value is required to correctly
>	 * detect columns different from this column to ensure that the correct
>	 * mouse cursor is set.
>	 */
>	private int colIndex = -1;
>
>	private static class LinkStyler extends Styler {
>
>		private final boolean underline;
>
>		public LinkStyler(boolean underline) {
>			this.underline = underline;
>		}
>
>		public final void applyStyles(TextStyle textStyle) {
>			textStyle.underline = underline;
>		}
>
>	}
>
>	private MouseTrackListener listener = new MouseTrackListener() {
>
>		public void mouseHover(MouseEvent e) {
>		}
>
>		public void mouseExit(MouseEvent e) {
>			resetCursor();
>		}
>
>		public void mouseEnter(MouseEvent e) {
>			handleCursor(e);
>		}
>	};
>
>	private MouseMoveListener listener2 = new MouseMoveListener() {
>
>		public void mouseMove(MouseEvent e) {
>			handleCursor(e);
>		}
>
>	};
>
>	private MouseListener listener3 = new MouseAdapter() {
>
>		public void mouseDown(MouseEvent e) {
>			if (e.count != 2) {
>				handleMouseDown(e);
>			}
>		}
>
>		public void mouseDoubleClick(MouseEvent e) {
>			handleMouseDown(e);
>		}
>
>		private final void handleMouseDown(MouseEvent e) {
>			Point pt = new Point(e.x, e.y);
>			ViewerCell cell = getViewer().getCell(pt);
>			if (cell != null && isLinkCell(cell)) {
>				viewerCtrl.setCursor(busyCursor);
>				linkActivated(cell.getElement());
>				viewerCtrl.setCursor(linkCursor);
>			}
>		}
>
>	};
>
>	private final void handleCursor(MouseEvent e) {
>		Point pt = new Point(e.x, e.y);
>		ViewerCell cell = getViewer().getCell(pt);
>		if (cell != null && isLinkCell(cell)) {
>			if (!linkEntered) {
>				viewerCtrl.setCursor(linkCursor);
>				linkEntered = true;
>			}
>		} else {
>			resetCursor();
>		}
>	}
>
>	private final void resetCursor() {
>		if (linkEntered) {
>			viewerCtrl.setCursor(null);
>			linkEntered = false;
>		}
>	}
>
>	private final boolean isLinkCell(ViewerCell cell) {
>		final int colIdx = cell.getColumnIndex();
>		if (colIdx == colIndex) {
>			Object element = cell.getElement();
>			return isLink(element);
>		} else {
>			return false;
>		}
>	}
>
>	/**
>	 * Subclasses may override. If their implementation is stateful, they need
>	 * to ensure that the function return value is set, before a call to
>	 * {@link #initialize(ColumnViewer, ViewerColumn)} has finished. A possible
>	 * strategy is to override this {@code initialize} method as well and to set
>	 * the state which determines the result of this function before
>	 * the super class implementation has been called.
>	 * 
>	 * @return whether links will be underlined or not. The default
>	 * implementation returns {@code true}.
>	 * @see #initialize(ColumnViewer, ViewerColumn)
>	 */
>	public boolean underlineLink() {
>		return true;
>	}
>
>	/**
>	 * Subclasses may override. If their implementation is stateful, they need
>	 * to ensure that the function return value is set, before a call to
>	 * {@link #initialize(ColumnViewer, ViewerColumn)} has finished. A possible
>	 * strategy is to override this {@code initialize} method as well and to set
>	 * the state which determines the result of this function before
>	 * the super class implementation has been called. This class does
>	 * not automatically free the color resources, implementors have to
>	 * provide their own resource management to ensure that. It is recommended
>	 * to use {@link #toColor(LinkColor, Display)} where possible, which takes
>	 * care of the management.
>	 * 
>	 * @return The color used for links. The default implementation uses the
>	 * color corresponding to {@code LinkColor.Normal}.
>	 * @see #initialize(ColumnViewer, ViewerColumn)
>	 * @see #toColor(LinkColor, Display)
>	 */
>	public Color linkColor(Display disp) {
>		return toColor(LinkColor.Normal, disp);
>	}
>
>	/**
>	 * Initializes the label provider. Subclasses may override, but shall call
>	 * the super class method.
>	 * 
>	 * @see #underlineLink()
>	 * @see #linkColor(Display)
>	 */
>	public void initialize(ColumnViewer viewer, ViewerColumn column) {
>		super.initialize(viewer, column);
>		boolean theUnderlineLink = underlineLink();
>		Control theControl = viewer.getControl();
>		Display disp = theControl.getDisplay();
>		Color theLinkColor = linkColor(disp);
>		viewerCtrl = theControl;
>		linkColor = theLinkColor;
>		if (linkColor == null)
>			linkColor = disp.getSystemColor(SWT.COLOR_BLUE);
>		linkCursor = disp.getSystemCursor(SWT.CURSOR_HAND);
>		busyCursor = disp.getSystemCursor(SWT.CURSOR_WAIT);
>		viewerCtrl.addMouseTrackListener(listener);
>		viewerCtrl.addMouseMoveListener(listener2);
>		viewerCtrl.addMouseListener(listener3);
>		styler = new LinkStyler(theUnderlineLink);
>	}
>
>	public final void update(ViewerCell cell) {
>		if (colIndex == -1) {
>			colIndex = cell.getColumnIndex();
>		}
>		Object element = cell.getElement();
>		String text = getLinkText(element);
>		if (text != null) {
>			StyledString styledString = new StyledString(text, styler);
>			cell.setText(styledString.toString());
>			cell.setStyleRanges(styledString.getStyleRanges());
>			cell.setForeground(linkColor);
>		} else {
>			updateNonLink(cell);
>		}
>		super.update(cell);
>	}
>
>	/**
>	 * A helper function that automatically ensures that any null or empty
>	 * string returns {@code null} and thus users don't have to provide their
>	 * own logic that ensures that an empty string is presented with hyper-link
>	 * mouse cursor.
>	 * 
>	 * @param s
>	 * The link text or {@code null}
>	 * @return Returns {@code null}, if the text is {@code null} or an empty
>	 * string, otherwise the text.
>	 * @see #getLinkText(Object)
>	 */
>	public static final String emptyToNull(String s) {
>		return (s == null || s.length() == 0) ? null : s;
>	}
>
>	/**
>	 * Convenience function to get a typical hyper link color value. Callers
>	 * shall not dispose the returned color value.
>	 * 
>	 * @param c
>	 * the color specifier
>	 * @param disp
>	 * The display the color shall retrieved from
>	 * @return the color value corresponding to the given enumerator, which
>	 * shall not be {@code null}.
>	 */
>	public static final Color toColor(LinkColor c, Display disp) {
>		if (c == LinkColor.Active)
>			return JFaceColors.getActiveHyperlinkText(disp);
>		else if (c == LinkColor.Normal)
>			return JFaceColors.getHyperlinkText(disp);
>		else
>			return disp.getSystemColor(SWT.COLOR_BLUE);
>	}
>
>	/**
>	 * Used to determine whether a model element corresponds to a link. The
>	 * method return value shall be equivalent to the test {@code
>	 * getLinkText(element) != null}, which is also the default behavior.
>	 * Subclasses may override, but shall satisfy the above mentioned
>	 * equivalence; this allows an implementation to provide an optimized test.
>	 * 
>	 * @param element
>	 * a model element corresponding to the column of this label
>	 * provider.
>	 * @return Whether the element corresponds to a link or not.
>	 * @see #getLinkText(Object)
>	 */
>	protected boolean isLink(Object element) {
>		String text = getLinkText(element);
>		return text != null;
>	}
>
>	/**
>	 * @param element
>	 * a model element corresponding to the column of this label
>	 * provider.
>	 * @return the link text representation of the element, or {@code null}, if
>	 * no such link should be shown (This mean that a link text of
>	 * length 0 will also show a link-specific cursor representation).
>	 * @see #isLink(Object)
>	 */
>	protected abstract String getLinkText(Object element);
>
>	/**
>	 * This method is invoked, if a link cell is activated by a mouse click
>	 * inside the link client area, i.e. if the column index corresponds to that
>	 * of this label provider and if {@link #isLink(Object)} returns {@code
>	 * true}.
>	 * 
>	 * @param element
>	 * the model element
>	 */
>	protected abstract void linkActivated(Object element);
>
>	/**
>	 * This method is invoked as part of {@link #update(ViewerCell)}, when
>	 * {@link #getLinkText(Object)} returns {@code null}. The default
>	 * implementation just sets empty text, style range, and fore ground color.
>	 * Subclasses may override and are not required to invoke the super class
>	 * method.
>	 * 
>	 * @param cell
>	 * @see #update(ViewerCell)
>	 */
>	protected void updateNonLink(ViewerCell cell) {
>		cell.setText(null);
>		cell.setStyleRanges(null);
>		cell.setForeground(null);
>	}
>
>	public void dispose() {
>		if (viewerCtrl != null && !viewerCtrl.isDisposed()) {
>			if (listener != null) {
>				viewerCtrl.removeMouseTrackListener(listener);
>				listener = null;
>			}
>			if (listener2 != null) {
>				viewerCtrl.removeMouseMoveListener(listener2);
>				listener2 = null;
>			}
>			if (listener3 != null) {
>				viewerCtrl.removeMouseListener(listener3);
>				listener3 = null;
>			}
>			linkCursor = null;
>			busyCursor = null;
>			linkColor = null;
>			viewerCtrl = null;
>		}
>		super.dispose();
>	}
>
>}

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Attachments on bug 289341: 147094