/******************************************************************************* * Copyright (c) 2000, 2013 IBM Corporation 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: * IBM Corporation - initial API and implementation *******************************************************************************/ package org.eclipse.swt.widgets; import org.eclipse.swt.*; import org.eclipse.swt.internal.gtk.*; import org.eclipse.swt.graphics.*; import org.eclipse.swt.events.*; import org.eclipse.swt.accessibility.*; /** * Instances of this class represent a selectable * user interface object that displays a text with * links. * <p> * <dl> * <dt><b>Styles:</b></dt> * <dd>(none)</dd> * <dt><b>Events:</b></dt> * <dd>Selection</dd> * </dl> * <p> * IMPORTANT: This class is <em>not</em> intended to be subclassed. * </p> * * @see <a href="http://www.eclipse.org/swt/snippets/#link">Link snippets</a> * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a> * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> * * @since 3.1 * @noextend This class is not intended to be subclassed by clients. */ public class Link extends Control { String text; TextLayout layout; Color linkColor, disabledColor; Point [] offsets; Point selection; String [] ids; int [] mnemonics; int focusIndex; static final RGB LINK_DISABLED_FOREGROUND = new RGB (172, 168, 153); /** * Constructs a new instance of this class given its parent * and a style value describing its behavior and appearance. * <p> * The style value is either one of the style constants defined in * class <code>SWT</code> which is applicable to instances of this * class, or must be built by <em>bitwise OR</em>'ing together * (that is, using the <code>int</code> "|" operator) two or more * of those <code>SWT</code> style constants. The class description * lists the style constants that are applicable to the class. * Style bits are also inherited from superclasses. * </p> * * @param parent a composite control which will be the parent of the new instance (cannot be null) * @param style the style of control to construct * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the parent is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> * </ul> * * @see Widget#checkSubclass * @see Widget#getStyle */ public Link (Composite parent, int style) { super (parent, style); } /** * Adds the listener to the collection of listeners who will * be notified when the control is selected by the user, by sending * it one of the messages defined in the <code>SelectionListener</code> * interface. * <p> * <code>widgetSelected</code> is called when the control is selected by the user. * <code>widgetDefaultSelected</code> is not called. * </p> * * @param listener the listener which should be notified * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> * * @see SelectionListener * @see #removeSelectionListener * @see SelectionEvent */ public void addSelectionListener (SelectionListener listener) { checkWidget (); if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); TypedListener typedListener = new TypedListener (listener); addListener (SWT.Selection, typedListener); addListener (SWT.DefaultSelection, typedListener); } @Override public Point computeSize (int wHint, int hHint, boolean changed) { checkWidget (); if (wHint != SWT.DEFAULT && wHint < 0) wHint = 0; if (hHint != SWT.DEFAULT && hHint < 0) hHint = 0; int width, height; int layoutWidth = layout.getWidth (); //TEMPORARY CODE if (wHint == 0) { layout.setWidth (1); Rectangle rect = layout.getBounds (); width = 0; height = rect.height; } else { layout.setWidth (wHint); Rectangle rect = layout.getBounds (); width = rect.width; height = rect.height; } layout.setWidth (layoutWidth); if (wHint != SWT.DEFAULT) width = wHint; if (hHint != SWT.DEFAULT) height = hHint; int border = getBorderWidth (); width += border * 2; height += border * 2; return new Point (width, height); } @Override void createHandle(int index) { state |= HANDLE | THEME_BACKGROUND; handle = OS.g_object_new (display.gtk_fixed_get_type (), 0); if (handle == 0) error (SWT.ERROR_NO_HANDLES); gtk_widget_set_has_window (handle, true); gtk_widget_set_can_focus (handle, true); layout = new TextLayout (display); linkColor = display.getSystemColor(SWT.COLOR_LINK_FOREGROUND); disabledColor = new Color (display, LINK_DISABLED_FOREGROUND); offsets = new Point [0]; ids = new String [0]; mnemonics = new int [0]; selection = new Point (-1, -1); focusIndex = -1; } @Override void createWidget (int index) { super.createWidget (index); layout.setFont (getFont ()); text = ""; initAccessible (); } @Override void drawWidget(GC gc) { int selStart = selection.x; int selEnd = selection.y; if (selStart > selEnd) { selStart = selection.y; selEnd = selection.x; } // temporary code to disable text selection selStart = selEnd = -1; if ((state & DISABLED) != 0) gc.setForeground (disabledColor); layout.draw (gc, 0, 0, selStart, selEnd, null, null); if (hasFocus () && focusIndex != -1) { Rectangle [] rects = getRectangles (focusIndex); for (int i = 0; i < rects.length; i++) { Rectangle rect = rects [i]; gc.drawFocus (rect.x, rect.y, rect.width, rect.height); } } } @Override void enableWidget (boolean enabled) { super.enableWidget (enabled); if (isDisposed ()) return; TextStyle linkStyle = new TextStyle (null, enabled ? linkColor : disabledColor, null); linkStyle.underline = true; for (int i = 0; i < offsets.length; i++) { Point point = offsets [i]; layout.setStyle (linkStyle, point.x, point.y); } redraw (); } @Override void fixStyle () { fixStyle (handle); } void initAccessible () { Accessible accessible = getAccessible (); accessible.addAccessibleListener (new AccessibleAdapter () { @Override public void getName (AccessibleEvent e) { e.result = parse (text); } }); accessible.addAccessibleControlListener (new AccessibleControlAdapter () { @Override public void getChildAtPoint (AccessibleControlEvent e) { e.childID = ACC.CHILDID_SELF; } @Override public void getLocation (AccessibleControlEvent e) { Rectangle rect = display.map (getParent (), null, getBounds ()); e.x = rect.x; e.y = rect.y; e.width = rect.width; e.height = rect.height; } @Override public void getChildCount (AccessibleControlEvent e) { e.detail = 0; } @Override public void getRole (AccessibleControlEvent e) { e.detail = ACC.ROLE_LINK; } @Override public void getState (AccessibleControlEvent e) { e.detail = ACC.STATE_FOCUSABLE; if (hasFocus ()) e.detail |= ACC.STATE_FOCUSED; } @Override public void getDefaultAction (AccessibleControlEvent e) { e.result = SWT.getMessage ("SWT_Press"); //$NON-NLS-1$ } @Override public void getSelection (AccessibleControlEvent e) { if (hasFocus ()) e.childID = ACC.CHILDID_SELF; } @Override public void getFocus (AccessibleControlEvent e) { if (hasFocus ()) e.childID = ACC.CHILDID_SELF; } }); } @Override String getNameText () { return getText (); } Rectangle [] getRectangles (int linkIndex) { int lineCount = layout.getLineCount (); Rectangle [] rects = new Rectangle [lineCount]; int [] lineOffsets = layout.getLineOffsets (); Point point = offsets [linkIndex]; int lineStart = 1; while (point.x > lineOffsets [lineStart]) lineStart++; int lineEnd = 1; while (point.y > lineOffsets [lineEnd]) lineEnd++; int index = 0; if (lineStart == lineEnd) { rects [index++] = layout.getBounds (point.x, point.y); } else { rects [index++] = layout.getBounds (point.x, lineOffsets [lineStart]-1); rects [index++] = layout.getBounds (lineOffsets [lineEnd-1], point.y); if (lineEnd - lineStart > 1) { for (int i = lineStart; i < lineEnd - 1; i++) { rects [index++] = layout.getLineBounds (i); } } } if (rects.length != index) { Rectangle [] tmp = new Rectangle [index]; System.arraycopy (rects, 0, tmp, 0, index); rects = tmp; } return rects; } @Override int getClientWidth () { if ((state & ZERO_WIDTH) != 0) return 0; GtkAllocation allocation = new GtkAllocation(); gtk_widget_get_allocation (handle, allocation); return allocation.width; } /** * Returns the receiver's text, which will be an empty * string if it has never been set. * * @return the receiver's text * * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public String getText () { checkWidget (); return text; } @Override long /*int*/ gtk_button_press_event (long /*int*/ widget, long /*int*/ event) { long /*int*/ result = super.gtk_button_press_event (widget, event); if (result != 0) return result; GdkEventButton gdkEvent = new GdkEventButton (); OS.memmove (gdkEvent, event, GdkEventButton.sizeof); if (gdkEvent.button == 1 && gdkEvent.type == OS.GDK_BUTTON_PRESS) { if (focusIndex != -1) setFocus (); int x = (int) gdkEvent.x; int y = (int) gdkEvent.y; if ((style & SWT.MIRRORED) != 0) x = getClientWidth () - x; int offset = layout.getOffset (x, y, null); int oldSelectionX = selection.x; int oldSelectionY = selection.y; selection.x = offset; selection.y = -1; if (oldSelectionX != -1 && oldSelectionY != -1) { if (oldSelectionX > oldSelectionY) { int temp = oldSelectionX; oldSelectionX = oldSelectionY; oldSelectionY = temp; } Rectangle rect = layout.getBounds (oldSelectionX, oldSelectionY); redraw (rect.x, rect.y, rect.width, rect.height, false); } for (int j = 0; j < offsets.length; j++) { Rectangle [] rects = getRectangles (j); for (int i = 0; i < rects.length; i++) { Rectangle rect = rects [i]; if (rect.contains (x, y)) { focusIndex = j; redraw (); return result; } } } } return result; } @Override long /*int*/ gtk_button_release_event (long /*int*/ widget, long /*int*/ event) { long /*int*/ result = super.gtk_button_release_event (widget, event); if (result != 0) return result; if (focusIndex == -1) return result; GdkEventButton gdkEvent = new GdkEventButton (); OS.memmove (gdkEvent, event, GdkEventButton.sizeof); if (gdkEvent.button == 1) { int x = (int) gdkEvent.x; int y = (int) gdkEvent.y; if ((style & SWT.MIRRORED) != 0) x = getClientWidth () - x; Rectangle [] rects = getRectangles (focusIndex); for (int i = 0; i < rects.length; i++) { Rectangle rect = rects [i]; if (rect.contains (x, y)) { Event ev = new Event (); ev.text = ids [focusIndex]; sendSelectionEvent (SWT.Selection, ev, true); return result; } } } return result; } @Override long /*int*/ gtk_event_after (long /*int*/ widget, long /*int*/ gdkEvent) { long /*int*/ result = super.gtk_event_after (widget, gdkEvent); GdkEvent event = new GdkEvent (); OS.memmove (event, gdkEvent, GdkEvent.sizeof); switch (event.type) { case OS.GDK_FOCUS_CHANGE: redraw (); break; } return result; } @Override long /*int*/ gtk_key_press_event (long /*int*/ widget, long /*int*/ eventPtr) { long /*int*/ result = super.gtk_key_press_event (widget, eventPtr); if (result != 0) return result; if (focusIndex == -1) return result; GdkEventKey gdkEvent = new GdkEventKey (); OS.memmove (gdkEvent, eventPtr, GdkEventKey.sizeof); switch (gdkEvent.keyval) { case OS.GDK_Return: case OS.GDK_KP_Enter: case OS.GDK_space: Event event = new Event (); event.text = ids [focusIndex]; sendSelectionEvent (SWT.Selection, event, true); break; case OS.GDK_Tab: if (focusIndex < offsets.length - 1) { focusIndex++; redraw (); } break; case OS.GDK_ISO_Left_Tab: if (focusIndex > 0) { focusIndex--; redraw (); } break; } return result; } @Override long /*int*/ gtk_motion_notify_event (long /*int*/ widget, long /*int*/ event) { long /*int*/ result = super.gtk_motion_notify_event (widget, event); if (result != 0) return result; GdkEventMotion gdkEvent = new GdkEventMotion (); OS.memmove (gdkEvent, event, GdkEventMotion.sizeof); int x = (int) gdkEvent.x; int y = (int) gdkEvent.y; if ((style & SWT.MIRRORED) != 0) x = getClientWidth () - x; if ((gdkEvent.state & OS.GDK_BUTTON1_MASK) != 0) { int oldSelection = selection.y; selection.y = layout.getOffset (x, y, null); if (selection.y != oldSelection) { int newSelection = selection.y; if (oldSelection > newSelection) { int temp = oldSelection; oldSelection = newSelection; newSelection = temp; } Rectangle rect = layout.getBounds (oldSelection, newSelection); redraw (rect.x, rect.y, rect.width, rect.height, false); } } else { for (int j = 0; j < offsets.length; j++) { Rectangle [] rects = getRectangles (j); for (int i = 0; i < rects.length; i++) { Rectangle rect = rects [i]; if (rect.contains (x, y)) { setCursor (display.getSystemCursor (SWT.CURSOR_HAND)); return result; } } } setCursor (null); } return result; } @Override boolean hooksPaint () { return true; } @Override boolean mnemonicHit (char key) { char uckey = Character.toUpperCase (key); String parsedText = layout.getText(); for (int i = 0; i < mnemonics.length - 1; i++) { if (mnemonics[i] != -1) { char mnemonic = parsedText.charAt(mnemonics[i]); if (uckey == Character.toUpperCase (mnemonic)) { if (!setFocus ()) return false; focusIndex = i; redraw (); return true; } } } return false; } @Override boolean mnemonicMatch (char key) { char uckey = Character.toUpperCase (key); String parsedText = layout.getText(); for (int i = 0; i < mnemonics.length - 1; i++) { if (mnemonics[i] != -1) { char mnemonic = parsedText.charAt(mnemonics[i]); if (uckey == Character.toUpperCase (mnemonic)) { return true; } } } return false; } @Override void releaseWidget () { super.releaseWidget (); if (layout != null) layout.dispose (); layout = null; linkColor = null; if (disabledColor != null) disabledColor.dispose (); disabledColor = null; offsets = null; ids = null; mnemonics = null; text = null; } /** * Removes the listener from the collection of listeners who will * be notified when the control is selected by the user. * * @param listener the listener which should no longer be notified * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the listener is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> * * @see SelectionListener * @see #addSelectionListener */ public void removeSelectionListener (SelectionListener listener) { checkWidget (); if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); if (eventTable == null) return; eventTable.unhook (SWT.Selection, listener); eventTable.unhook (SWT.DefaultSelection, listener); } String parse (String string) { int length = string.length (); offsets = new Point [length / 4]; ids = new String [length / 4]; mnemonics = new int [length / 4 + 1]; StringBuffer result = new StringBuffer (); char [] buffer = new char [length]; string.getChars (0, string.length (), buffer, 0); int index = 0, state = 0, linkIndex = 0; int start = 0, tagStart = 0, linkStart = 0, endtagStart = 0, refStart = 0; while (index < length) { char c = Character.toLowerCase (buffer [index]); switch (state) { case 0: if (c == '<') { tagStart = index; state++; } break; case 1: if (c == 'a') state++; break; case 2: switch (c) { case 'h': state = 7; break; case '>': linkStart = index + 1; state++; break; default: if (Character.isWhitespace(c)) break; else state = 13; } break; case 3: if (c == '<') { endtagStart = index; state++; } break; case 4: state = c == '/' ? state + 1 : 3; break; case 5: state = c == 'a' ? state + 1 : 3; break; case 6: if (c == '>') { mnemonics [linkIndex] = parseMnemonics (buffer, start, tagStart, result); int offset = result.length (); parseMnemonics (buffer, linkStart, endtagStart, result); offsets [linkIndex] = new Point (offset, result.length () - 1); if (ids [linkIndex] == null) { ids [linkIndex] = new String (buffer, linkStart, endtagStart - linkStart); } linkIndex++; start = tagStart = linkStart = endtagStart = refStart = index + 1; state = 0; } else { state = 3; } break; case 7: state = c == 'r' ? state + 1 : 0; break; case 8: state = c == 'e' ? state + 1 : 0; break; case 9: state = c == 'f' ? state + 1 : 0; break; case 10: state = c == '=' ? state + 1 : 0; break; case 11: if (c == '"') { state++; refStart = index + 1; } else { state = 0; } break; case 12: if (c == '"') { ids[linkIndex] = new String (buffer, refStart, index - refStart); state = 2; } break; case 13: if (Character.isWhitespace (c)) { state = 0; } else if (c == '='){ state++; } break; case 14: state = c == '"' ? state + 1 : 0; break; case 15: if (c == '"') state = 2; break; default: state = 0; break; } index++; } if (start < length) { int tmp = parseMnemonics (buffer, start, tagStart, result); int mnemonic = parseMnemonics (buffer, Math.max (tagStart, linkStart), length, result); if (mnemonic == -1) mnemonic = tmp; mnemonics [linkIndex] = mnemonic; } else { mnemonics [linkIndex] = -1; } if (offsets.length != linkIndex) { Point [] newOffsets = new Point [linkIndex]; System.arraycopy (offsets, 0, newOffsets, 0, linkIndex); offsets = newOffsets; String [] newIDs = new String [linkIndex]; System.arraycopy (ids, 0, newIDs, 0, linkIndex); ids = newIDs; int [] newMnemonics = new int [linkIndex + 1]; System.arraycopy (mnemonics, 0, newMnemonics, 0, linkIndex + 1); mnemonics = newMnemonics; } return result.toString (); } int parseMnemonics (char[] buffer, int start, int end, StringBuffer result) { int mnemonic = -1, index = start; while (index < end) { if (buffer [index] == '&') { if (index + 1 < end && buffer [index + 1] == '&') { result.append (buffer [index]); index++; } else { mnemonic = result.length(); } } else { result.append (buffer [index]); } index++; } return mnemonic; } @Override int setBounds(int x, int y, int width, int height, boolean move, boolean resize) { int result = super.setBounds (x, y, width,height, move, resize); if ((result & RESIZED) != 0) { layout.setWidth (width > 0 ? width : -1); redraw (); } return result; } @Override void setFontDescription (long /*int*/ font) { super.setFontDescription (font); layout.setFont (Font.gtk_new (display, font)); } @Override void setOrientation (boolean create) { super.setOrientation (create); layout.setOrientation (style & (SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT)); if (!create) redraw (true); } /** * Sets the receiver's text. * <p> * The string can contain both regular text and hyperlinks. A hyperlink * is delimited by an anchor tag, <A> and </A>. Within an * anchor, a single HREF attribute is supported. When a hyperlink is * selected, the text field of the selection event contains either the * text of the hyperlink or the value of its HREF, if one was specified. * In the rare case of identical hyperlinks within the same string, the * HREF attribute can be used to distinguish between them. The string may * include the mnemonic character and line delimiters. The only delimiter * the HREF attribute supports is the quotation mark ("). * </p> * <p> * Mnemonics are indicated by an '&' that causes the next * character to be the mnemonic. The receiver can have a * mnemonic in the text preceding each link. When the user presses a * key sequence that matches the mnemonic, focus is assigned * to the link that follows the text. Mnemonics in links and in * the trailing text are ignored. On most platforms, * the mnemonic appears underlined but may be emphasised in a * platform specific manner. The mnemonic indicator character * '&' can be escaped by doubling it in the string, causing * a single '&' to be displayed. * </p> * * @param string the new text * * @exception IllegalArgumentException <ul> * <li>ERROR_NULL_ARGUMENT - if the text is null</li> * </ul> * @exception SWTException <ul> * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> * </ul> */ public void setText (String string) { checkWidget (); if (string == null) error (SWT.ERROR_NULL_ARGUMENT); if (string.equals (text)) return; text = string; layout.setText (parse (string)); focusIndex = offsets.length > 0 ? 0 : -1; selection.x = selection.y = -1; boolean enabled = (state & DISABLED) == 0; TextStyle linkStyle = new TextStyle (null, enabled ? linkColor : disabledColor, null); linkStyle.underline = true; int [] bidiSegments = new int [offsets.length*2]; for (int i = 0; i < offsets.length; i++) { Point point = offsets [i]; layout.setStyle (linkStyle, point.x, point.y); bidiSegments[i*2] = point.x; bidiSegments[i*2+1] = point.y+1; } layout.setSegments (bidiSegments); TextStyle mnemonicStyle = new TextStyle (null, null, null); mnemonicStyle.underline = true; for (int i = 0; i < mnemonics.length; i++) { int mnemonic = mnemonics [i]; if (mnemonic != -1) { layout.setStyle (mnemonicStyle, mnemonic, mnemonic); } } redraw (); } @Override void showWidget () { super.showWidget (); fixStyle (handle); } @Override int traversalCode (int key, GdkEventKey event) { if (offsets.length == 0) return 0; int bits = super.traversalCode (key, event); if (key == OS.GDK_Tab && focusIndex < offsets.length - 1) { return bits & ~SWT.TRAVERSE_TAB_NEXT; } if (key == OS.GDK_ISO_Left_Tab && focusIndex > 0) { return bits & ~SWT.TRAVERSE_TAB_PREVIOUS; } return bits; } }