Class Label

java.lang.Object

org.eclipse.swt.widgets.Widget

org.eclipse.swt.widgets.Control

org.eclipse.swt.widgets.Label

All Implemented Interfaces:

Drawable

public class Label
extends Control

Instances of this class represent a non-selectable user interface object that displays a string or image. When SEPARATOR is specified, displays a single vertical or horizontal line.

Shadow styles are hints and may not be honored by the platform. To create a separator label with the default shadow style for the platform, do not specify a shadow style.

Styles:

SEPARATOR, HORIZONTAL, VERTICAL

SHADOW_IN, SHADOW_OUT, SHADOW_NONE

CENTER, LEFT, RIGHT, WRAP

Events:

(none)

Note: Only one of SHADOW_IN, SHADOW_OUT and SHADOW_NONE may be specified. SHADOW_NONE is a HINT. Only one of HORIZONTAL and VERTICAL may be specified. Only one of CENTER, LEFT and RIGHT may be specified.

IMPORTANT: This class is not intended to be subclassed.

See Also:

• Label snippets
• SWT Example: ControlExample
• Sample code and further information

Field Summary

Fields

Modifier and Type	Field	Description
(package private) long	boxHandle
(package private) long	frameHandle
(package private) Image	image
(package private) long	imageHandle
(package private) long	labelHandle
(package private) String	text

Fields inherited from class Control

accessible, autoScale, backgroundAlpha, backgroundImage, cachedNoBackground, checkScaleFactor, cssBackground, cssForeground, cursor, DISABLE_EMOJI, dragDetectionQueue, dragGesture, drawCount, drawRegion, enableWindow, eventRegion, firstFixedHandle, fixedHandle, font, gestureBegin, gestureEnd, gestureRotation, gestureSwipe, gestureZoom, keyController, labelRelation, lastInput, layoutData, menu, mouseDown, panGesture, parent, provider, redrawWindow, region, regionHandle, rotateGesture, toolTipText, zoomGesture

Fields inherited from class Widget

ACTIVATE, ACTIVATE_INVERSE, AUTO_TEXT_DIRECTION, BACKGROUND, BACKSPACE, BACKSPACE_INVERSE, BUTTON_PRESS_EVENT, BUTTON_PRESS_EVENT_INVERSE, BUTTON_RELEASE_EVENT, BUTTON_RELEASE_EVENT_INVERSE, CANVAS, CHANGE_VALUE, CHANGED, CHECK_SUBWINDOW, CLICKED, CLOSE_REQUEST, COMMIT, COMPUTE_SIZE, CONFIGURE_EVENT, COPY_CLIPBOARD, COPY_CLIPBOARD_INVERSE, CREATE_MENU_PROXY, CUT_CLIPBOARD, CUT_CLIPBOARD_INVERSE, data, DAY_SELECTED, DAY_SELECTED_DOUBLE_CLICK, DECELERATE, DEFAULT_HEIGHT, DEFAULT_WIDTH, DELETE_EVENT, DELETE_FROM_CURSOR, DELETE_FROM_CURSOR_INVERSE, DELETE_RANGE, DELETE_TEXT, DIRECTION_CHANGED, DISABLED, display, DISPOSE_SENT, DISPOSED, DPI_CHANGED, DRAG_DETECT, DRAW, ENTER, ENTER_NOTIFY_EVENT, EVENT, EVENT_AFTER, eventTable, EXPAND_COLLAPSE_CURSOR_ROW, EXPOSE_EVENT, EXPOSE_EVENT_INVERSE, FOCUS, FOCUS_IN, FOCUS_IN_EVENT, FOCUS_OUT, FOCUS_OUT_EVENT, FONT, FOREGROUND, FOREIGN_HANDLE, gdkSeatGrabPrepareFunc, GESTURE_PRESSED, GESTURE_RELEASED, GRAB_FOCUS, handle, HANDLE, HAS_AUTO_DIRECTION, HIDDEN, HIDE, ICON_RELEASE, IM_UPDATE, INPUT, INSERT_TEXT, IS_ACTIVE, KEY_CHECK_SUBWINDOW, KEY_GTK_CSS, KEY_PRESS_EVENT, KEY_PRESSED, KEY_RELEASE_EVENT, KEY_RELEASED, KEYED_DATA, LAST_SIGNAL, LAYOUT_CHANGED, LAYOUT_CHILD, LAYOUT_NEEDED, LEAVE, LEAVE_NOTIFY_EVENT, MAP, MAP_EVENT, MENU, MNEMONIC_ACTIVATE, MONTH_CHANGED, MOTION, MOTION_INVERSE, MOTION_NOTIFY_EVENT, MOTION_NOTIFY_EVENT_INVERSE, MOVE_CURSOR, MOVE_CURSOR_INVERSE, MOVE_FOCUS, MOVED, NOTIFY_DEFAULT_HEIGHT, NOTIFY_DEFAULT_WIDTH, NOTIFY_MAXIMIZED, NOTIFY_STATE, OBSCURED, OUTPUT, PARENT_BACKGROUND, PASTE_CLIPBOARD, PASTE_CLIPBOARD_INVERSE, POPPED_UP, POPULATE_POPUP, POPUP_MENU, PREEDIT_CHANGED, REALIZE, RELEASED, RESIZED, ROW_ACTIVATED, ROW_DELETED, ROW_HAS_CHILD_TOGGLED, ROW_INSERTED, SCROLL, SCROLL_BEGIN, SCROLL_CHILD, SCROLL_END, SCROLL_EVENT, SELECT, SELECTION_DONE, SHOW, SHOW_HELP, SIZE_ALLOCATE, SIZE_ALLOCATE_GTK4, SKIN_NEEDED, START_INTERACTIVE_SEARCH, state, STATUS_ICON_POPUP_MENU, style, STYLE_UPDATED, SWITCH_PAGE, TEST_COLLAPSE_ROW, TEST_EXPAND_ROW, TEXT_BUFFER_INSERT_TEXT, THEME_BACKGROUND, TOGGLED, UNMAP, UNMAP_EVENT, UNREALIZE, VALUE_CHANGED, WINDOW_STATE_EVENT, ZERO_HEIGHT, ZERO_WIDTH

Constructor Summary

Constructors

Constructor	Description
Label(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

Modifier and Type	Method	Description
(package private) void	addRelation(Control control)
(package private) static int	checkStyle(int style)
(package private) Point	computeNativeSize(long h, int wHint, int hHint, boolean changed)
(package private) Point	computeSizeInPixels(int wHint, int hHint, boolean changed)
(package private) void	createHandle(int index)
(package private) void	createWidget(int index)
(package private) long	cssHandle()
(package private) void	deregister()
(package private) long	dpiChanged(long object, long arg0)
(package private) long	eventHandle()
int	getAlignment()	Returns a value which describes the position of the text or image in the receiver.
(package private) int	getBorderWidthInPixels()
Image	getImage()	Returns the receiver's image if it has one, or null if it does not.
(package private) String	getNameText()
String	getText()	Returns the receiver's text, which will be an empty string if it has never been set or if the receiver is a SEPARATOR label.
private void	gtk_label_set_align(float xalign, float yalign)
(package private) void	hookEvents()
(package private) boolean	isDescribedByLabel()
(package private) boolean	mnemonicHit(char key)
(package private) boolean	mnemonicMatch(char key)
(package private) void	register()
(package private) void	releaseHandle()
(package private) void	releaseWidget()
(package private) void	resizeHandle(int width, int height)
(package private) void	setAlignment()
void	setAlignment(int alignment)	Controls how text and images will be displayed in the receiver.
(package private) int	setBounds(int x, int y, int width, int height, boolean move, boolean resize)
(package private) void	setFontDescription(long font)
(package private) void	setForegroundGdkRGBA(GdkRGBA rgba)
void	setImage(Image image)	Sets the receiver's image to the argument, which may be null indicating that no image should be displayed.
(package private) void	setOrientation(boolean create)
void	setText(String string)	Sets the receiver's text.
(package private) void	setWidgetBackground()
(package private) void	showWidget()
(package private) long	windowProc(long handle, long arg0, long user_data)

Methods inherited from class Control

_getAccessible, _getShell, addControlListener, addDragDetectListener, addFocusListener, addGestureListener, addHelpListener, addKeyListener, addMenuDetectListener, addMouseListener, addMouseMoveListener, addMouseTrackListener, addMouseWheelListener, addPaintListener, addTouchListener, addTraverseListener, adjustChildClipping, cairoClipRegion, cairoCopyRegion, cairoDisposeRegion, checkBackground, checkBorder, checkBuffered, checkMirrored, checkSubwindow, cleanupEnableWindow, computeSize, computeSize, computeSizeInPixels, computeTabGroup, computeTabList, computeTabRoot, containedInRegion, defaultBackground, defaultFont, destroyWidget, dragDetect, dragDetect, dragDetect, dragDetect, drawBackground, drawGripper, drawWidget, enableWidget, enterExitHandle, eventSurface, eventWindow, filterKey, findBackgroundControl, findMenus, fixChildren, fixFocus, fixGdkEventTypeValues, fixModal, fixParentGdkResource, fixStyle, fixStyle, flushQueueOnDnd, focusHandle, fontHandle, forceFocus, forceFocus, forceResize, gestureBeginProc, gestureEndProc, gestureHandle, getAccessible, getBackground, getBackgroundGdkRGBA, getBackgroundImage, getBaseGdkRGBA, getBgGdkRGBA, getBorderWidth, getBounds, getBoundsInPixels, getClientWidth, getContextBackgroundGdkRGBA, getContextColorGdkRGBA, getControl, getControlOrigin, getCursor, getDragDetect, getEnabled, getFont, getFontDescription, getForeground, getForegroundGdkRGBA, getIMCaretPos, getLayoutData, getLocation, getLocationInPixels, getMenu, getMonitor, getOrientation, getParent, getPath, getRegion, getShell, getSize, getSizeInPixels, getSurfaceOrigin, getTextDirection, getThickness, getToolTipText, getTouchEnabled, getVisible, getWindowOrigin, gtk_button_press_event, gtk_button_press_event, gtk_button_release_event, gtk_commit, gtk_css_provider_load_from_css, gtk_draw, gtk_enter_notify_event, gtk_focus, gtk_focus_in_event, gtk_focus_out_event, gtk_gesture_press_event, gtk_gesture_release_event, gtk_label_set_align, gtk_leave_notify_event, gtk_mnemonic_activate, gtk_motion_notify_event, gtk_preedit_changed, gtk_realize, gtk_scroll_event, gtk_style_context_get_border, gtk_style_context_get_padding, gtk_style_updated, gtk_unrealize, gtk_widget_reparent, gtk_widget_set_align, gtk3_event_after, gtk3_key_press_event, gtk3_key_release_event, gtk3_popup_menu, gtk3_show_help, gtk4_draw, gtk4_enter_event, gtk4_focus_enter_event, gtk4_focus_leave_event, gtk4_focus_window_event, gtk4_key_press_event, gtk4_key_release_event, gtk4_leave_event, gtk4_motion_event, gtk4_scroll_event, hasFocus, hooksPaint, hoverProc, imHandle, internal_dispose_GC, internal_new_GC, isActive, isAutoScalable, isEnabled, isFocusAncestor, isFocusControl, isFocusHandle, isReparentable, isShowing, isTabGroup, isTabItem, isVisible, magnifyProc, markLayout, menuShell, moveAbove, moveBelow, moveChildren, moveHandle, mustBeVisibleOnInitBounds, pack, pack, paintHandle, paintSurface, paintWindow, print, printWidget, printWindow, redraw, redraw, redraw, redrawChildren, redrawWidget, release, releaseParent, removeControlListener, removeDragDetectListener, removeFocusListener, removeGestureListener, removeHelpListener, removeKeyListener, removeMenuDetectListener, removeMouseListener, removeMouseMoveListener, removeMouseTrackListener, removeMouseWheelListener, removePaintListener, removeRelation, removeTouchListener, removeTraverseListener, requestLayout, resizeCalculationsGTK3, restackWindow, rotateProc, sendDragEvent, sendFocusEvent, sendGestureEvent, sendGestureEvent, sendGestureEvent, sendHelpEvent, sendLeaveNotify, sendMouseEvent, sendMouseEvent, setBackground, setBackground, setBackgroundGdkRGBA, setBackgroundGdkRGBA, setBackgroundGdkRGBA, setBackgroundImage, setBackgroundSurface, setBounds, setBounds, setBoundsInPixels, setBoundsInPixels, setCapture, setCursor, setCursor, setDragDetect, setEnabled, setFocus, setFont, setForeground, setForegroundGdkRGBA, setInitialBounds, setLayoutData, setLocation, setLocation, setLocationInPixels, setLocationInPixels, setMenu, setOrientation, setParent, setParentBackground, setParentGdkResource, setRadioSelection, setRedraw, setRegion, setRelations, setSize, setSize, setSizeInPixels, setSizeInPixels, setTabItemFocus, setTextDirection, setToolTipText, setToolTipText, setTouchEnabled, setVisible, setZOrder, setZOrder, showMenu, showMenu, sort, swipeProc, toControl, toControl, toDisplay, toDisplay, toDisplayInPixels, topHandle, translateMnemonic, translateMnemonic, translateTraversal, traversalCode, traverse, traverse, traverse, traverse, traverse, traverseEscape, traverseGroup, traverseItem, traverseMnemonic, traversePage, traverseReturn, update, update, updateBackgroundMode, updateLayout, wantDragDropDetection

Methods inherited from class Widget

_addListener, addDisposeListener, addListener, addTypedListener, cellDataProc, checkBits, checkOpen, checkOrientation, checkParent, checkSubclass, checkWidget, convertPangoFontDescriptionToCss, dispose, enterMotionProc, error, filterProc, filters, fixMnemonic, fixMnemonic, fixMnemonic, focusProc, fontHeight, gdk_event_free, gdk_event_get_state, gdk_event_get_surface_or_window, gdk_pointer_grab, gdk_pointer_ungrab, gdk_surface_get_size, gdk_window_get_size, GdkSeatGrabPrepareFunc, gesturePressReleaseProc, getData, getData, getDisplay, getListeners, getName, getStyle, getTypedListeners, gtk_activate, gtk_adjustment_get, gtk_box_new, gtk_box_pack_end, gtk_box_set_child_packing, gtk_cell_renderer_get_preferred_size, gtk_change_value, gtk_changed, gtk_clicked, gtk_close_request, gtk_configure_event, gtk_container_get_border_width_or_margin, gtk_container_set_border_width, gtk_create_menu_proxy, gtk_day_selected, gtk_day_selected_double_click, gtk_delete_event, gtk_delete_range, gtk_delete_text, gtk_expand_collapse_cursor_row, gtk_grab_focus, gtk_hide, gtk_icon_release, gtk_input, gtk_insert_text, gtk_map, gtk_map_event, gtk_menu_popped_up, gtk_month_changed, gtk_move_focus, gtk_output, gtk_populate_popup, gtk_row_activated, gtk_row_has_child_toggled, gtk_scroll_child, gtk_select, gtk_selection_done, gtk_show, gtk_size_allocate, gtk_start_interactive_search, gtk_status_icon_popup_menu, gtk_switch_page, gtk_test_collapse_row, gtk_test_expand_row, gtk_text_buffer_insert_text, gtk_timer, gtk_toggled, gtk_tree_view_column_cell_get_position, gtk_unmap, gtk_unmap_event, gtk_value_changed, gtk_widget_get_preferred_size, gtk_widget_get_surface, gtk_widget_get_window, gtk_widget_hide, gtk_widget_show, gtk_widget_size_allocate, gtk_window_state_event, hooks, isAutoDirection, isDisposed, isListening, isValidSubclass, isValidThread, keyPressReleaseProc, leaveProc, mnemonicHit, mnemonicMatch, notifyCreationTracker, notifyDisposalTracker, notifyListeners, notifyProc, notifyState, postEvent, postEvent, releaseChildren, removeDisposeListener, removeListener, removeListener, removeListener, removeTypedListener, rendererGetPreferredWidthProc, rendererRenderProc, rendererSnapshotProc, reskin, reskinChildren, reskinWidget, scrollProc, sendEvent, sendEvent, sendEvent, sendEvent, sendIMKeyEvent, sendKeyEvent, sendSelectionEvent, sendSelectionEvent, setButtonState, setData, setData, setFontDescription, setInputState, setKeyState, setLocationState, setTabGroupFocus, setToolTipText, shellMapProc, sizeAllocateProc, sizeRequestProc, snapshotToDraw, timerProc, toString, translateTraversal, windowActiveProc, windowProc, windowProc, windowProc, windowProc

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

frameHandle

long frameHandle

labelHandle

long labelHandle

imageHandle

long imageHandle

boxHandle

long boxHandle

image

Image image

text

String text

Constructor Details

Label

public Label(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 composite control which will be the parent of the new instance (cannot be null)

style - the style of control to construct

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the parent is null

SWTException -

• ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
• ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass

See Also:

• SWT.SEPARATOR
• SWT.HORIZONTAL
• SWT.VERTICAL
• SWT.SHADOW_IN
• SWT.SHADOW_OUT
• SWT.SHADOW_NONE
• SWT.CENTER
• SWT.LEFT
• SWT.RIGHT
• SWT.WRAP
• Widget.checkSubclass()
• Widget.getStyle()

Method Details

checkStyle

static int checkStyle(int style)

addRelation

void addRelation(Control control)

Overrides:

addRelation in class Control

computeNativeSize

Point computeNativeSize(long h,
 int wHint,
 int hHint,
 boolean changed)

Overrides:

computeNativeSize in class Control

computeSizeInPixels

Point computeSizeInPixels(int wHint,
 int hHint,
 boolean changed)

Overrides:

computeSizeInPixels in class Control

createHandle

void createHandle(int index)

Overrides:

createHandle in class Widget

createWidget

void createWidget(int index)

Overrides:

createWidget in class Control

deregister

void deregister()

Overrides:

deregister in class Control

eventHandle

long eventHandle()

Overrides:

eventHandle in class Control

cssHandle

long cssHandle()

Overrides:

cssHandle in class Widget

getAlignment

public int getAlignment()

Returns a value which describes the position of the text or image in the receiver. The value will be one of LEFT, RIGHT or CENTER unless the receiver is a SEPARATOR label, in which case, NONE is returned.

Returns:

the alignment

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

getBorderWidthInPixels

int getBorderWidthInPixels()

Overrides:

getBorderWidthInPixels in class Control

getImage

public Image getImage()

Returns the receiver's image if it has one, or null if it does not.

Returns:

the receiver's image

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

getNameText

String getNameText()

Overrides:

getNameText in class Widget

getText

public String getText()

Returns the receiver's text, which will be an empty string if it has never been set or if the receiver is a SEPARATOR label.

Returns:

the receiver's text

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

hookEvents

void hookEvents()

Overrides:

hookEvents in class Control

isDescribedByLabel

boolean isDescribedByLabel()

Overrides:

isDescribedByLabel in class Control

mnemonicHit

boolean mnemonicHit(char key)

Overrides:

mnemonicHit in class Control

mnemonicMatch

boolean mnemonicMatch(char key)

Overrides:

mnemonicMatch in class Control

register

void register()

Overrides:

register in class Control

releaseHandle

void releaseHandle()

Overrides:

releaseHandle in class Control

releaseWidget

void releaseWidget()

Overrides:

releaseWidget in class Control

resizeHandle

void resizeHandle(int width,
 int height)

Overrides:

resizeHandle in class Control

setAlignment

public void setAlignment(int alignment)

Controls how text and images will be displayed in the receiver. The argument should be one of LEFT, RIGHT or CENTER. If the receiver is a SEPARATOR label, the argument is ignored and the alignment is not changed.

Parameters:

alignment - the new alignment

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

setAlignment

void setAlignment()

gtk_label_set_align

private void gtk_label_set_align(float xalign,
 float yalign)

setBounds

int setBounds(int x,
 int y,
 int width,
 int height,
 boolean move,
 boolean resize)

Overrides:

setBounds in class Control

setFontDescription

void setFontDescription(long font)

Overrides:

setFontDescription in class Control

setForegroundGdkRGBA

void setForegroundGdkRGBA(GdkRGBA rgba)

Overrides:

setForegroundGdkRGBA in class Control

setOrientation

void setOrientation(boolean create)

Overrides:

setOrientation in class Control

setImage

public void setImage(Image image)

Sets the receiver's image to the argument, which may be null indicating that no image should be displayed.

Parameters:

image - the image to display on the receiver (may be null)

Throws:

IllegalArgumentException -

• ERROR_INVALID_ARGUMENT - if the image has been disposed

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(String string)

Sets the receiver's text.

This method sets the widget label. The label may include the mnemonic character and line delimiters.

Mnemonics are indicated by an '&' that causes the next character to be the mnemonic. When the user presses a key sequence that matches the mnemonic, focus is assigned to the control that follows the label. 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.

Note: If control characters like '\n', '\t' etc. are used in the string, then the behavior is platform dependent.

Parameters:

string - the new text

Throws:

IllegalArgumentException -

• ERROR_NULL_ARGUMENT - if the text is null

SWTException -

• ERROR_WIDGET_DISPOSED - if the receiver has been disposed
• ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver

setWidgetBackground

void setWidgetBackground()

Overrides:

setWidgetBackground in class Control

showWidget

void showWidget()

Overrides:

showWidget in class Control

windowProc

long windowProc(long handle,
 long arg0,
 long user_data)

Overrides:

windowProc in class Control

dpiChanged

long dpiChanged(long object,
 long arg0)

Overrides:

dpiChanged in class Widget