package org.eclipse.bpel.common.ui.details.widgets; import org.eclipse.swt.SWT; import org.eclipse.swt.SWTException; import org.eclipse.swt.accessibility.ACC; import org.eclipse.swt.accessibility.Accessible; import org.eclipse.swt.accessibility.AccessibleAdapter; import org.eclipse.swt.accessibility.AccessibleControlAdapter; import org.eclipse.swt.accessibility.AccessibleControlEvent; import org.eclipse.swt.accessibility.AccessibleEvent; import org.eclipse.swt.events.DisposeEvent; import org.eclipse.swt.events.DisposeListener; import org.eclipse.swt.events.PaintEvent; import org.eclipse.swt.events.PaintListener; import org.eclipse.swt.events.TraverseEvent; import org.eclipse.swt.events.TraverseListener; import org.eclipse.swt.graphics.Color; import org.eclipse.swt.graphics.Font; import org.eclipse.swt.graphics.GC; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.widgets.Canvas; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Display; /** * A Label which supports aligned text and/or an image and different border styles. * <p> * If there is not enough space a CLabel uses the following strategy to fit the * information into the available space: * <pre> * ignores the indent in left align mode * ignores the image and the gap * shortens the text by replacing the center portion of the label with an ellipsis * shortens the text by removing the center portion of the label * </pre> * <p> * <dl> * <dt><b>Styles:</b> * <dd>LEFT, RIGHT, CENTER, SHADOW_IN, SHADOW_OUT, SHADOW_NONE</dd> * <dt><b>Events:</b> * <dd></dd> * </dl> * * </p><p> * IMPORTANT: This class is <em>not</em> intended to be subclassed. * </p> */ public class DecoratedLabel extends Canvas { /** Gap between icon and text */ private static final int GAP = 5; /** Left and right margins */ private static final int INDENT = 2; /** a string inserted in the middle of text that has been shortened */ private static final String ELLIPSIS = "..."; //$NON-NLS-1$ // could use the ellipsis glyph on some platforms "\u2026" /** the alignment. Either CENTER, RIGHT, LEFT. Default is LEFT*/ private int align = SWT.LEFT; private int hIndent = 0; private int vIndent = INDENT; /** the current text */ private String text; /** the current icon */ private Image image; // The tooltip is used for two purposes - the application can set // a tooltip or the tooltip can be used to display the full text when the // the text has been truncated due to the label being too short. // The appToolTip stores the tooltip set by the application. Control.tooltiptext // contains whatever tooltip is currently being displayed. private String appToolTipText; private Image backgroundImage; private Color[] gradientColors; private int[] gradientPercents; private boolean gradientVertical; private Color background; private static int DRAW_FLAGS = SWT.DRAW_MNEMONIC | SWT.DRAW_TAB | SWT.DRAW_TRANSPARENT | SWT.DRAW_DELIMITER; /** * 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 widget which will be the parent of the new instance (cannot be null) * @param style the style of widget 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> * </ul> * * @see SWT#LEFT * @see SWT#RIGHT * @see SWT#CENTER * @see SWT#SHADOW_IN * @see SWT#SHADOW_OUT * @see SWT#SHADOW_NONE * @see #getStyle() */ public DecoratedLabel(Composite parent, int style) { super(parent, checkStyle(style)); if ((style & (SWT.CENTER | SWT.RIGHT)) == 0) style |= SWT.LEFT; if ((style & SWT.CENTER) != 0) align = SWT.CENTER; if ((style & SWT.RIGHT) != 0) align = SWT.RIGHT; if ((style & SWT.LEFT) != 0) align = SWT.LEFT; addPaintListener(new PaintListener(){ public void paintControl(PaintEvent event) { onPaint(event); } }); addDisposeListener(new DisposeListener(){ public void widgetDisposed(DisposeEvent event) { onDispose(event); } }); addTraverseListener(new TraverseListener() { public void keyTraversed(TraverseEvent event) { if (event.detail == SWT.TRAVERSE_MNEMONIC) { onMnemonic(event); } } }); initAccessible(); } /** * Check the style bits to ensure that no invalid styles are applied. */ private static int checkStyle (int style) { if ((style & SWT.BORDER) != 0) style |= SWT.SHADOW_IN; int mask = SWT.SHADOW_IN | SWT.SHADOW_OUT | SWT.SHADOW_NONE | SWT.LEFT_TO_RIGHT | SWT.RIGHT_TO_LEFT; style = style & mask; style |= SWT.NO_FOCUS | SWT.DOUBLE_BUFFERED; return style; } //protected void checkSubclass () { // String name = getClass().getName (); // String validName = CLabel.class.getName(); // if (!validName.equals(name)) { // SWT.error (SWT.ERROR_INVALID_SUBCLASS); // } //} @Override public Point computeSize(int wHint, int hHint, boolean changed) { checkWidget(); Point e = getTotalSize(image, text); if (wHint == SWT.DEFAULT){ e.x += 2*hIndent; } else { e.x = wHint; } if (hHint == SWT.DEFAULT) { e.y += 2*vIndent; } else { e.y = hHint; } return e; } /** * Draw a rectangle in the given colors. */ private void drawBevelRect(GC gc, int x, int y, int w, int h, Color topleft, Color bottomright) { gc.setForeground(bottomright); gc.drawLine(x+w, y, x+w, y+h); gc.drawLine(x, y+h, x+w, y+h); gc.setForeground(topleft); gc.drawLine(x, y, x+w-1, y); gc.drawLine(x, y, x, y+h-1); } /* * Return the lowercase of the first non-'&' character following * an '&' character in the given string. If there are no '&' * characters in the given string, return '\0'. */ char _findMnemonic (String string) { if (string == null) return '\0'; int index = 0; int length = string.length (); do { while (index < length && string.charAt (index) != '&') index++; if (++index >= length) return '\0'; if (string.charAt (index) != '&') return Character.toLowerCase (string.charAt (index)); index++; } while (index < length); return '\0'; } /** * Returns the alignment. * The alignment style (LEFT, CENTER or RIGHT) is returned. * * @return SWT.LEFT, SWT.RIGHT or SWT.CENTER */ public int getAlignment() { //checkWidget(); return align; } /** * Return the CLabel's image or <code>null</code>. * * @return the image of the label or null */ public Image getImage() { //checkWidget(); return image; } /** * Compute the minimum size. */ private Point getTotalSize(Image image, String text) { Point size = new Point(0, 0); if (image != null) { Rectangle r = image.getBounds(); size.x += r.width; size.y += r.height; } GC gc = new GC(this); if (text != null && text.length() > 0) { Point e = gc.textExtent(text, DRAW_FLAGS); size.x += e.x; size.y = Math.max(size.y, e.y); if (image != null) size.x += GAP; } else { size.y = Math.max(size.y, gc.getFontMetrics().getHeight()); } gc.dispose(); return size; } @Override public int getStyle () { int style = super.getStyle(); switch (align) { case SWT.RIGHT: style |= SWT.RIGHT; break; case SWT.CENTER: style |= SWT.CENTER; break; case SWT.LEFT: style |= SWT.LEFT; break; } return style; } /** * Return the Label's text. * * @return the text of the label or null */ public String getText() { //checkWidget(); return text; } @Override public String getToolTipText () { checkWidget(); return appToolTipText; } private void initAccessible() { Accessible accessible = getAccessible(); accessible.addAccessibleListener(new AccessibleAdapter() { @Override public void getName(AccessibleEvent e) { e.result = getText(); } @Override public void getHelp(AccessibleEvent e) { e.result = getToolTipText(); } @Override public void getKeyboardShortcut(AccessibleEvent e) { char mnemonic = _findMnemonic(DecoratedLabel.this.text); if (mnemonic != '\0') { e.result = "Alt+"+mnemonic; //$NON-NLS-1$ } } }); accessible.addAccessibleControlListener(new AccessibleControlAdapter() { @Override public void getChildAtPoint(AccessibleControlEvent e) { e.childID = ACC.CHILDID_SELF; } @Override public void getLocation(AccessibleControlEvent e) { Rectangle rect = getDisplay().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_LABEL; } @Override public void getState(AccessibleControlEvent e) { e.detail = ACC.STATE_READONLY; } }); } void onDispose(DisposeEvent event) { gradientColors = null; gradientPercents = null; backgroundImage = null; text = null; image = null; appToolTipText = null; } void onMnemonic(TraverseEvent event) { char mnemonic = _findMnemonic(text); if (mnemonic == '\0') return; if (Character.toLowerCase(event.character) != mnemonic) return; Composite control = this.getParent(); while (control != null) { Control [] children = control.getChildren(); int index = 0; while (index < children.length) { if (children [index] == this) break; index++; } index++; if (index < children.length) { if (children [index].setFocus ()) { event.doit = true; event.detail = SWT.TRAVERSE_NONE; } } control = control.getParent(); } } void onPaint(PaintEvent event) { Rectangle rect = getClientArea(); if (rect.width == 0 || rect.height == 0) return; boolean shortenText = false; String t = text; Image img = image; int availableWidth = Math.max(0, rect.width - 2*hIndent); Point extent = getTotalSize(img, t); if (extent.x > availableWidth) { img = null; extent = getTotalSize(img, t); if (extent.x > availableWidth) { shortenText = true; } } GC gc = event.gc; String[] lines = text == null ? null : splitString(text); // shorten the text if (shortenText) { extent.x = 0; for(int i = 0; i < lines.length; i++) { Point e = gc.textExtent(lines[i], DRAW_FLAGS); if (e.x > availableWidth) { lines[i] = shortenText(gc, lines[i], availableWidth); extent.x = Math.max(extent.x, getTotalSize(null, lines[i]).x); } else { extent.x = Math.max(extent.x, e.x); } } if (appToolTipText == null) { super.setToolTipText(text); } } else { super.setToolTipText(appToolTipText); } // determine horizontal position int x = rect.x + hIndent; if (align == SWT.CENTER) { x = (rect.width - extent.x)/2; } if (align == SWT.RIGHT) { x = rect.width - hIndent - extent.x; } // draw a background image behind the text try { if (backgroundImage != null) { // draw a background image behind the text Rectangle imageRect = backgroundImage.getBounds(); // tile image to fill space gc.setBackground(getBackground()); gc.fillRectangle(rect); int xPos = 0; while (xPos < rect.width) { int yPos = 0; while (yPos < rect.height) { gc.drawImage(backgroundImage, xPos, yPos); yPos += imageRect.height; } xPos += imageRect.width; } } else if (gradientColors != null) { // draw a gradient behind the text final Color oldBackground = gc.getBackground(); if (gradientColors.length == 1) { if (gradientColors[0] != null) gc.setBackground(gradientColors[0]); gc.fillRectangle(0, 0, rect.width, rect.height); } else { final Color oldForeground = gc.getForeground(); Color lastColor = gradientColors[0]; if (lastColor == null) lastColor = oldBackground; int pos = 0; for (int i = 0; i < gradientPercents.length; ++i) { gc.setForeground(lastColor); lastColor = gradientColors[i + 1]; if (lastColor == null) lastColor = oldBackground; gc.setBackground(lastColor); if (gradientVertical) { final int gradientHeight = (gradientPercents[i] * rect.height / 100) - pos; gc.fillGradientRectangle(0, pos, rect.width, gradientHeight, true); pos += gradientHeight; } else { final int gradientWidth = (gradientPercents[i] * rect.width / 100) - pos; gc.fillGradientRectangle(pos, 0, gradientWidth, rect.height, false); pos += gradientWidth; } } if (gradientVertical && pos < rect.height) { gc.setBackground(getBackground()); gc.fillRectangle(0, pos, rect.width, rect.height - pos); } if (!gradientVertical && pos < rect.width) { gc.setBackground(getBackground()); gc.fillRectangle(pos, 0, rect.width - pos, rect.height); } gc.setForeground(oldForeground); } gc.setBackground(oldBackground); } else { if (background != null || (getStyle() & SWT.DOUBLE_BUFFERED) == 0) { gc.setBackground(getBackground()); gc.fillRectangle(rect); } } } catch (SWTException e) { if ((getStyle() & SWT.DOUBLE_BUFFERED) == 0) { gc.setBackground(getBackground()); gc.fillRectangle(rect); } } // draw border int style = getStyle(); if ((style & SWT.SHADOW_IN) != 0 || (style & SWT.SHADOW_OUT) != 0) { paintBorder(gc, rect); } // draw the image if (img != null) { Rectangle imageRect = img.getBounds(); gc.drawImage(img, 0, 0, imageRect.width, imageRect.height, x, (rect.height-imageRect.height)/2, imageRect.width, imageRect.height); x += imageRect.width + GAP; extent.x -= imageRect.width + GAP; } // draw the text if (lines != null) { int lineHeight = gc.getFontMetrics().getHeight(); int textHeight = lines.length * lineHeight; int lineY = Math.max(vIndent, rect.y + (rect.height - textHeight) / 2); gc.setForeground(getForeground()); for (int i = 0; i < lines.length; i++) { int lineX = x; if (lines.length > 1) { if (align == SWT.CENTER) { int lineWidth = gc.textExtent(lines[i], DRAW_FLAGS).x; lineX = x + Math.max(0, (extent.x - lineWidth) / 2); } if (align == SWT.RIGHT) { int lineWidth = gc.textExtent(lines[i], DRAW_FLAGS).x; lineX = Math.max(x, rect.x + rect.width - hIndent - lineWidth); } } gc.drawText(lines[i], lineX, lineY, DRAW_FLAGS); lineY += lineHeight; } } } /** * Paint the Label's border. */ private void paintBorder(GC gc, Rectangle r) { Display disp= getDisplay(); Color c1 = null; Color c2 = null; int style = getStyle(); if ((style & SWT.SHADOW_IN) != 0) { c1 = disp.getSystemColor(SWT.COLOR_WIDGET_NORMAL_SHADOW); c2 = disp.getSystemColor(SWT.COLOR_WIDGET_HIGHLIGHT_SHADOW); } if ((style & SWT.SHADOW_OUT) != 0) { c1 = disp.getSystemColor(SWT.COLOR_WIDGET_LIGHT_SHADOW); c2 = disp.getSystemColor(SWT.COLOR_WIDGET_NORMAL_SHADOW); } if (c1 != null && c2 != null) { gc.setLineWidth(1); drawBevelRect(gc, r.x, r.y, r.width-1, r.height-1, c1, c2); } } /** * Set the alignment of the CLabel. * Use the values LEFT, CENTER and RIGHT to align image and text within the available space. * * @param align the alignment style of LEFT, RIGHT or CENTER * * @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> * <li>ERROR_INVALID_ARGUMENT - if the value of align is not one of SWT.LEFT, SWT.RIGHT or SWT.CENTER</li> * </ul> */ public void setAlignment(int align) { checkWidget(); if (align != SWT.LEFT && align != SWT.RIGHT && align != SWT.CENTER) { SWT.error(SWT.ERROR_INVALID_ARGUMENT); } if (this.align != align) { this.align = align; redraw(); } } @Override public void setBackground (Color color) { super.setBackground (color); // Are these settings the same as before? if (backgroundImage == null && gradientColors == null && gradientPercents == null) { if (color == null) { if (background == null) return; } else { if (color.equals(background)) return; } } background = color; backgroundImage = null; gradientColors = null; gradientPercents = null; redraw (); } /** * Specify a gradient of colours to be drawn in the background of the CLabel. * <p>For example, to draw a gradient that varies from dark blue to blue and then to * white and stays white for the right half of the label, use the following call * to setBackground:</p> * <pre> * clabel.setBackground(new Color[]{display.getSystemColor(SWT.COLOR_DARK_BLUE), * display.getSystemColor(SWT.COLOR_BLUE), * display.getSystemColor(SWT.COLOR_WHITE), * display.getSystemColor(SWT.COLOR_WHITE)}, * new int[] {25, 50, 100}); * </pre> * * @param colors an array of Color that specifies the colors to appear in the gradient * in order of appearance from left to right; The value <code>null</code> * clears the background gradient; the value <code>null</code> can be used * inside the array of Color to specify the background color. * @param percents an array of integers between 0 and 100 specifying the percent of the width * of the widget at which the color should change; the size of the percents * array must be one less than the size of the colors array. * * @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> * <li>ERROR_INVALID_ARGUMENT - if the values of colors and percents are not consistent</li> * </ul> */ public void setBackground(Color[] colors, int[] percents) { setBackground(colors, percents, false); } /** * Specify a gradient of colours to be drawn in the background of the CLabel. * <p>For example, to draw a gradient that varies from dark blue to white in the vertical, * direction use the following call * to setBackground:</p> * <pre> * clabel.setBackground(new Color[]{display.getSystemColor(SWT.COLOR_DARK_BLUE), * display.getSystemColor(SWT.COLOR_WHITE)}, * new int[] {100}, true); * </pre> * * @param colors an array of Color that specifies the colors to appear in the gradient * in order of appearance from left/top to right/bottom; The value <code>null</code> * clears the background gradient; the value <code>null</code> can be used * inside the array of Color to specify the background color. * @param percents an array of integers between 0 and 100 specifying the percent of the width/height * of the widget at which the color should change; the size of the percents * array must be one less than the size of the colors array. * @param vertical indicate the direction of the gradient. True is vertical and false is horizontal. * * @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> * <li>ERROR_INVALID_ARGUMENT - if the values of colors and percents are not consistent</li> * </ul> * * @since 3.0 */ public void setBackground(Color[] colors, int[] percents, boolean vertical) { checkWidget(); if (colors != null) { if (percents == null || percents.length != colors.length - 1) { SWT.error(SWT.ERROR_INVALID_ARGUMENT); } if (getDisplay().getDepth() < 15) { // Don't use gradients on low color displays colors = new Color[] {colors[colors.length - 1]}; percents = new int[] { }; } for (int i = 0; i < percents.length; i++) { if (percents[i] < 0 || percents[i] > 100) { SWT.error(SWT.ERROR_INVALID_ARGUMENT); } if (i > 0 && percents[i] < percents[i-1]) { SWT.error(SWT.ERROR_INVALID_ARGUMENT); } } } // Are these settings the same as before? final Color background = getBackground(); if (backgroundImage == null) { if ((gradientColors != null) && (colors != null) && (gradientColors.length == colors.length)) { boolean same = false; for (int i = 0; i < gradientColors.length; i++) { same = (gradientColors[i] == colors[i]) || ((gradientColors[i] == null) && (colors[i] == background)) || ((gradientColors[i] == background) && (colors[i] == null)); if (!same) break; } if (same) { for (int i = 0; i < gradientPercents.length; i++) { same = gradientPercents[i] == percents[i]; if (!same) break; } } if (same && this.gradientVertical == vertical) return; } } else { backgroundImage = null; } // Store the new settings if (colors == null) { gradientColors = null; gradientPercents = null; gradientVertical = false; } else { gradientColors = new Color[colors.length]; for (int i = 0; i < colors.length; ++i) gradientColors[i] = (colors[i] != null) ? colors[i] : background; gradientPercents = new int[percents.length]; for (int i = 0; i < percents.length; ++i) gradientPercents[i] = percents[i]; gradientVertical = vertical; } // Refresh with the new settings redraw(); } /** * Set the image to be drawn in the background of the label. * * @param image the image to be drawn in the background * * @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 setBackground(Image image) { checkWidget(); if (image == backgroundImage) return; if (image != null) { gradientColors = null; gradientPercents = null; } backgroundImage = image; redraw(); } @Override public void setFont(Font font) { super.setFont(font); redraw(); } /** * Set the label's Image. * The value <code>null</code> clears it. * * @param image the image to be displayed in the label or null * * @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 setImage(Image image) { checkWidget(); if (image != this.image) { this.image = image; redraw(); } } /** * Set the label's text. * The value <code>null</code> clears it. * * @param text the text to be displayed in the label or null * * @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 text) { checkWidget(); if (text == null) text = ""; //$NON-NLS-1$ if (! text.equals(this.text)) { this.text = text; redraw(); } } @Override public void setToolTipText (String string) { super.setToolTipText (string); appToolTipText = super.getToolTipText(); } /** * Shorten the given text <code>t</code> so that its length doesn't exceed * the given width. The default implementation replaces characters in the * center of the original string with an ellipsis ("..."). * Override if you need a different strategy. * * @param gc the gc to use for text measurement * @param t the text to shorten * @param width the width to shorten the text to, in pixels * @return the shortened text */ protected String shortenText(GC gc, String t, int width) { if (t == null) return null; int w = gc.textExtent(ELLIPSIS, DRAW_FLAGS).x; int l = t.length(); int pivot = l/2; int s = pivot; int e = pivot+1; while (s >= 0 && e < l) { String s1 = t.substring(0, s); String s2 = t.substring(e, l); int l1 = gc.textExtent(s1, DRAW_FLAGS).x; int l2 = gc.textExtent(s2, DRAW_FLAGS).x; if (l1+w+l2 < width) { t = s1 + ELLIPSIS + s2; break; } s--; e++; } return t; } private String[] splitString(String text) { String[] lines = new String[1]; int start = 0, pos; do { pos = text.indexOf('\n', start); if (pos == -1) { lines[lines.length - 1] = text.substring(start); } else { boolean crlf = (pos > 0) && (text.charAt(pos - 1) == '\r'); lines[lines.length - 1] = text.substring(start, pos - (crlf ? 1 : 0)); start = pos + 1; String[] newLines = new String[lines.length+1]; System.arraycopy(lines, 0, newLines, 0, lines.length); lines = newLines; } } while (pos != -1); return lines; } }