Eclipse Rich Ajax Platform

org.eclipse.swt.custom
Class CLabel

java.lang.Object
  extended by org.eclipse.swt.widgets.Widget
      extended by org.eclipse.swt.widgets.Control
          extended by org.eclipse.swt.widgets.Scrollable
              extended by org.eclipse.swt.widgets.Composite
                  extended by org.eclipse.swt.widgets.Canvas
                      extended by org.eclipse.swt.custom.CLabel
All Implemented Interfaces:
Adaptable, Drawable

public class CLabel
extends Canvas

A Label which supports aligned text and/or an image and different border styles.

If there is not enough space a CLabel uses the following strategy to fit the information into the available space:

                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
 

Styles:
LEFT, RIGHT, CENTER, SHADOW_IN, SHADOW_OUT, SHADOW_NONE
Events:

IMPORTANT: This class is not intended to be subclassed.

Since:
1.0

Constructor Summary
CLabel(Composite parent, int style)
          Constructs a new instance of this class given its parent and a style value describing its behavior and appearance.
 
Method Summary
 Point computeSize(int wHint, int hHint, boolean changed)
          Returns the preferred size of the receiver.
 int getAlignment()
          Returns the alignment.
 int getBottomMargin()
          Return the CLabel's bottom margin.
 Image getImage()
          Return the CLabel's image or null.
 int getLeftMargin()
          Return the CLabel's left margin.
 int getRightMargin()
          Return the CLabel's right margin.
 int getStyle()
          Returns the receiver's style information.
 java.lang.String getText()
          Return the Label's text.
 java.lang.String getToolTipText()
          Returns the receiver's tool tip text, or null if it has not been set.
 int getTopMargin()
          Return the CLabel's top margin.
 void setAlignment(int align)
          Set the alignment of the CLabel.
 void setBackground(Color color)
          Sets the receiver's background color to the color specified by the argument, or to the default system color for the control if the argument is null.
 void setBackground(Color[] colors, int[] percents)
          Specify a gradient of colours to be drawn in the background of the CLabel.
 void setBackground(Color[] colors, int[] percents, boolean vertical)
          Specify a gradient of colours to be drawn in the background of the CLabel.
 void setBackground(Image image)
          Set the image to be drawn in the background of the label.
 void setBottomMargin(int bottomMargin)
          Set the label's bottom margin, in pixels.
 void setData(java.lang.String key, java.lang.Object value)
          Sets the application defined property of the receiver with the specified name to the given value.
 void setFont(Font font)
          Sets the font that the receiver will use to paint textual information to the font specified by the argument, or to the default font for that kind of control if the argument is null.
 void setImage(Image image)
          Set the label's Image.
 void setLeftMargin(int leftMargin)
          Set the label's horizontal left margin, in pixels.
 void setMargins(int leftMargin, int topMargin, int rightMargin, int bottomMargin)
          Set the label's margins, in pixels.
 void setRightMargin(int rightMargin)
          Set the label's right margin, in pixels.
 void setText(java.lang.String text)
          Set the label's text.
 void setToolTipText(java.lang.String string)
          Sets the receiver's tool tip text to the argument, which may be null indicating that no tool tip text should be shown.
 void setTopMargin(int topMargin)
          Set the label's top margin, in pixels.
 
Methods inherited from class org.eclipse.swt.widgets.Canvas
addPaintListener, getAdapter, removePaintListener
 
Methods inherited from class org.eclipse.swt.widgets.Composite
changed, getBackgroundMode, getChildren, getLayout, getLayoutDeferred, getTabList, isLayoutDeferred, layout, layout, layout, layout, layout, setBackgroundMode, setFocus, setLayout, setLayoutDeferred, setTabList
 
Methods inherited from class org.eclipse.swt.widgets.Scrollable
computeTrim, getClientArea, getHorizontalBar, getVerticalBar
 
Methods inherited from class org.eclipse.swt.widgets.Control
addControlListener, addDragDetectListener, addFocusListener, addGestureListener, addHelpListener, addKeyListener, addMenuDetectListener, addMouseListener, addTouchListener, addTraverseListener, computeSize, forceFocus, getAccessible, getBackground, getBackgroundImage, getBorderWidth, getBounds, getCursor, getEnabled, getFont, getForeground, getLayoutData, getLocation, getMenu, getMonitor, getOrientation, getParent, getShell, getSize, getTouchEnabled, getVisible, isEnabled, isFocusControl, isReparentable, isVisible, moveAbove, moveBelow, pack, pack, redraw, redraw, removeControlListener, removeDragDetectListener, removeFocusListener, removeGestureListener, removeHelpListener, removeKeyListener, removeMenuDetectListener, removeMouseListener, removeTouchListener, removeTraverseListener, setBackgroundImage, setBounds, setBounds, setCursor, setEnabled, setForeground, setLayoutData, setLocation, setLocation, setMenu, setOrientation, setParent, setRedraw, setSize, setSize, setTouchEnabled, setVisible, toControl, toControl, toDisplay, toDisplay, update
 
Methods inherited from class org.eclipse.swt.widgets.Widget
addDisposeListener, addListener, checkSubclass, checkWidget, dispose, getData, getData, getDisplay, getListeners, isDisposed, isListening, notifyListeners, removeDisposeListener, removeListener, reskin, setData, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

CLabel

public CLabel(Composite parent,
              int style)
Constructs a new instance of this class given its parent and a style value describing its behavior and appearance.

The style value is either one of the style constants defined in class SWT which is applicable to instances of this class, or must be built by bitwise OR'ing together (that is, using the int "|" operator) two or more of those SWT style constants. The class description lists the style constants that are applicable to the class. Style bits are also inherited from superclasses.

Parameters:
parent - a widget which will be the parent of the new instance (cannot be null)
style - the style of widget to construct
Throws:
java.lang.IllegalArgumentException -
  • ERROR_NULL_ARGUMENT - if the parent is null
SWTException -
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
See Also:
SWT.LEFT, SWT.RIGHT, SWT.CENTER, SWT.SHADOW_IN, SWT.SHADOW_OUT, SWT.SHADOW_NONE, getStyle()
Method Detail

computeSize

public Point computeSize(int wHint,
                         int hHint,
                         boolean changed)
Description copied from class: Control
Returns the preferred size of the receiver.

The preferred size of a control is the size that it would best be displayed at. The width hint and height hint arguments allow the caller to ask a control questions such as "Given a particular width, how high does the control need to be to show all of the contents?" To indicate that the caller does not wish to constrain a particular dimension, the constant SWT.DEFAULT is passed for the hint.

If the changed flag is true, it indicates that the receiver's contents have changed, therefore any caches that a layout manager containing the control may have been keeping need to be flushed. When the control is resized, the changed flag will be false, so layout manager caches can be retained.

Overrides:
computeSize in class Composite
Parameters:
wHint - the width hint (can be SWT.DEFAULT)
hHint - the height hint (can be SWT.DEFAULT)
changed - true if the control's contents have changed, and false otherwise
Returns:
the preferred size of the control.
See Also:
Layout, Control.getBorderWidth(), Control.getBounds(), Control.getSize(), Control.pack(boolean), "computeTrim, getClientArea for controls that implement them"

getAlignment

public int getAlignment()
Returns the alignment. The alignment style (LEFT, CENTER or RIGHT) is returned.

Returns:
SWT.LEFT, SWT.RIGHT or SWT.CENTER

getImage

public Image getImage()
Return the CLabel's image or null.

Returns:
the image of the label or null

getStyle

public int getStyle()
Description copied from class: Widget
Returns the receiver's style information.

Note that the value which is returned by this method may not match the value which was provided to the constructor when the receiver was created. This can occur when the underlying operating system does not support a particular combination of requested styles. For example, if the platform widget used to implement a particular SWT widget always has scroll bars, the result of calling this method would always have the SWT.H_SCROLL and SWT.V_SCROLL bits set.

Overrides:
getStyle in class Widget
Returns:
the style bits

getText

public java.lang.String getText()
Return the Label's text.

Returns:
the text of the label or null

getToolTipText

public java.lang.String getToolTipText()
Description copied from class: Control
Returns the receiver's tool tip text, or null if it has not been set.

Overrides:
getToolTipText in class Control
Returns:
the receiver's tool tip text

setAlignment

public void setAlignment(int align)
Set the alignment of the CLabel. Use the values LEFT, CENTER and RIGHT to align image and text within the available space.

Parameters:
align - the alignment style of LEFT, RIGHT or CENTER
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
  • ERROR_INVALID_ARGUMENT - if the value of align is not one of SWT.LEFT, SWT.RIGHT or SWT.CENTER

setBackground

public void setBackground(Color color)
Description copied from class: Control
Sets the receiver's background color to the color specified by the argument, or to the default system color for the control if the argument is null.

Overrides:
setBackground in class Control
Parameters:
color - the new color (or null)

setBackground

public void setBackground(Image image)
Set the image to be drawn in the background of the label.

Parameters:
image - the image to be drawn in the background
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

setBackground

public void setBackground(Color[] colors,
                          int[] percents)
Specify a gradient of colours to be drawn in the background of the CLabel.

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:

  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});
 

Parameters:
colors - an array of Color that specifies the colors to appear in the gradient in order of appearance from left to right; The value null clears the background gradient; the value null can be used inside the array of Color to specify the background color.
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.
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
  • ERROR_INVALID_ARGUMENT - if the values of colors and percents are not consistent
Since:
1.4

setBackground

public void setBackground(Color[] colors,
                          int[] percents,
                          boolean vertical)
Specify a gradient of colours to be drawn in the background of the CLabel.

For example, to draw a gradient that varies from dark blue to white in the vertical, direction use the following call to setBackground:

  clabel.setBackground(new Color[]{display.getSystemColor(SWT.COLOR_DARK_BLUE),
                               display.getSystemColor(SWT.COLOR_WHITE)},
                     new int[] {100}, true);
 

Parameters:
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 null clears the background gradient; the value null can be used inside the array of Color to specify the background color.
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.
vertical - indicate the direction of the gradient. True is vertical and false is horizontal.
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
  • ERROR_INVALID_ARGUMENT - if the values of colors and percents are not consistent
Since:
1.4

setFont

public void setFont(Font font)
Description copied from class: Control
Sets the font that the receiver will use to paint textual information to the font specified by the argument, or to the default font for that kind of control if the argument is null.

Overrides:
setFont in class Control
Parameters:
font - the new font (or null)

setImage

public void setImage(Image image)
Set the label's Image. The value null clears it.

Parameters:
image - the image to be displayed in the label or null
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

setText

public void setText(java.lang.String text)
Set the label's text. The value null clears it.

Parameters:
text - the text to be displayed in the label or null
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

setToolTipText

public void setToolTipText(java.lang.String string)
Description copied from class: Control
Sets the receiver's tool tip text to the argument, which may be null indicating that no tool tip text should be shown.

Overrides:
setToolTipText in class Control
Parameters:
string - the new tool tip text (or null)

setMargins

public void setMargins(int leftMargin,
                       int topMargin,
                       int rightMargin,
                       int bottomMargin)
Set the label's margins, in pixels.

Parameters:
leftMargin - the left margin.
topMargin - the top margin.
rightMargin - the right margin.
bottomMargin - the bottom margin.
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
Since:
1.3

setLeftMargin

public void setLeftMargin(int leftMargin)
Set the label's horizontal left margin, in pixels.

Parameters:
leftMargin - the left margin of the label, which must be equal to or greater than zero
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
Since:
1.3

getLeftMargin

public int getLeftMargin()
Return the CLabel's left margin.

Returns:
the left margin of the label
Since:
1.3

setTopMargin

public void setTopMargin(int topMargin)
Set the label's top margin, in pixels.

Parameters:
topMargin - the top margin of the label, which must be equal to or greater than zero
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
Since:
1.3

getTopMargin

public int getTopMargin()
Return the CLabel's top margin.

Returns:
the top margin of the label
Since:
1.3

setRightMargin

public void setRightMargin(int rightMargin)
Set the label's right margin, in pixels.

Parameters:
rightMargin - the right margin of the label, which must be equal to or greater than zero
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
Since:
1.3

getRightMargin

public int getRightMargin()
Return the CLabel's right margin.

Returns:
the right margin of the label
Since:
1.3

setBottomMargin

public void setBottomMargin(int bottomMargin)
Set the label's bottom margin, in pixels.

Parameters:
bottomMargin - the bottom margin of the label, which must be equal to or greater than zero
Throws:
SWTException -
  • ERROR_WIDGET_DISPOSED - if the receiver has been disposed
  • ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
Since:
1.3

getBottomMargin

public int getBottomMargin()
Return the CLabel's bottom margin.

Returns:
the bottom margin of the label
Since:
1.3

setData

public void setData(java.lang.String key,
                    java.lang.Object value)
Description copied from class: Widget
Sets the application defined property of the receiver with the specified name to the given value.

Applications may associate arbitrary objects with the receiver in this fashion. If the objects stored in the properties need to be notified when the widget is disposed of, it is the application's responsibility to hook the Dispose event on the widget and do so.

Overrides:
setData in class Widget
Parameters:
key - the name of the property
value - the new value for the property
See Also:
Widget.getData(String)

Eclipse Rich Ajax Platform

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