Package com.google.gwt.user.client

Class Event

  • public class Event
extends NativeEvent

    An opaque handle to a native DOM Event. An Event cannot be created directly. Instead, use the Event type when returning a native DOM event from JSNI methods. An Event passed back into JSNI becomes the original DOM event the Event was created from, and can be accessed in JavaScript code as expected. This is typically done by calling methods in the DOM class.

    • Field Detail

      • ONBLUR

        public static final int ONBLUR
        Fired when an element loses keyboard focus.
        See Also:
        Constant Field Values

      • ONCHANGE

        public static final int ONCHANGE
        Fired when the value of an input element changes.
        See Also:
        Constant Field Values

      • ONCLICK

        public static final int ONCLICK
        Fired when the user clicks on an element.
        See Also:
        Constant Field Values

      • ONDBLCLICK

        public static final int ONDBLCLICK
        Fired when the user double-clicks on an element.
        See Also:
        Constant Field Values

      • ONERROR

        public static final int ONERROR
        Fired when an image encounters an error.
        See Also:
        Constant Field Values

      • ONFOCUS

        public static final int ONFOCUS
        Fired when an element receives keyboard focus.
        See Also:
        Constant Field Values

      • ONGESTURECHANGE

        public static final int ONGESTURECHANGE
        Fired when the user gesture changes.
        See Also:
        Constant Field Values

      • ONGESTUREEND

        public static final int ONGESTUREEND
        Fired when the user gesture ends.
        See Also:
        Constant Field Values

      • ONGESTURESTART

        public static final int ONGESTURESTART
        Fired when the user gesture starts.
        See Also:
        Constant Field Values

      • ONKEYDOWN

        public static final int ONKEYDOWN
        Fired when the user depresses a key.
        See Also:
        Constant Field Values

      • ONKEYPRESS

        public static final int ONKEYPRESS
        Fired when the a character is generated from a keypress (either directly or through auto-repeat).
        See Also:
        Constant Field Values

      • ONKEYUP

        public static final int ONKEYUP
        Fired when the user releases a key.
        See Also:
        Constant Field Values

      • ONLOAD

        public static final int ONLOAD
        Fired when an element (normally an IMG) finishes loading.
        See Also:
        Constant Field Values

      • ONLOSECAPTURE

        public static final int ONLOSECAPTURE
        Fired when an element that has mouse capture loses it.
        See Also:
        Constant Field Values

      • ONMOUSEDOWN

        public static final int ONMOUSEDOWN
        Fired when the user depresses a mouse button over an element.
        See Also:
        Constant Field Values

      • ONMOUSEMOVE

        public static final int ONMOUSEMOVE
        Fired when the mouse is moved within an element's area.
        See Also:
        Constant Field Values

      • ONMOUSEOUT

        public static final int ONMOUSEOUT
        Fired when the mouse is moved out of an element's area.
        See Also:
        Constant Field Values

      • ONMOUSEOVER

        public static final int ONMOUSEOVER
        Fired when the mouse is moved into an element's area.
        See Also:
        Constant Field Values

      • ONMOUSEUP

        public static final int ONMOUSEUP
        Fired when the user releases a mouse button over an element.
        See Also:
        Constant Field Values

      • ONMOUSEWHEEL

        public static final int ONMOUSEWHEEL
        Fired when the user scrolls the mouse wheel over an element.
        See Also:
        Constant Field Values

      • ONPASTE

        public static final int ONPASTE
        Fired when the user pastes text into an input element.
        See Also:
        Constant Field Values

      • ONSCROLL

        public static final int ONSCROLL
        Fired when a scrollable element's scroll offset changes.
        See Also:
        Constant Field Values

      • ONTOUCHCANCEL

        public static final int ONTOUCHCANCEL
        Fired when the user cancels touching an element.
        See Also:
        Constant Field Values

      • ONTOUCHEND

        public static final int ONTOUCHEND
        Fired when the user ends touching an element.
        See Also:
        Constant Field Values

      • ONTOUCHMOVE

        public static final int ONTOUCHMOVE
        Fired when the user moves while touching an element.
        See Also:
        Constant Field Values

      • ONTOUCHSTART

        public static final int ONTOUCHSTART
        Fired when the user starts touching an element.
        See Also:
        Constant Field Values

      • ONCONTEXTMENU

        public static final int ONCONTEXTMENU
        Fired when the user requests an element's context menu (usually by right-clicking).
        See Also:
        Constant Field Values

      • FOCUSEVENTS

        public static final int FOCUSEVENTS
        A bit-mask covering both focus events (focus and blur).
        See Also:
        Constant Field Values

      • KEYEVENTS

        public static final int KEYEVENTS
        A bit-mask covering all keyboard events (down, up, and press).
        See Also:
        Constant Field Values

      • MOUSEEVENTS

        public static final int MOUSEEVENTS
        A bit-mask covering all mouse events (down, up, move, over, and out), but not click, dblclick, or wheel events.
        See Also:
        Constant Field Values

      • TOUCHEVENTS

        public static final int TOUCHEVENTS
        A bit-mask covering all touch events (start, move, end, cancel).
        See Also:
        Constant Field Values

      • GESTUREEVENTS

        public static final int GESTUREEVENTS
        A bit-mask covering all gesture events (start, change, end).
        See Also:
        Constant Field Values

      • UNDEFINED

        @Deprecated
public static final int UNDEFINED
        Deprecated.
        Value returned by accessors when the actual integer value is undefined. In Development Mode, most accessors assert that the requested attribute is reliable across all supported browsers.
        See Also:
        Event, Constant Field Values

      • handlers

        static HandlerManager handlers
        The list of Event.NativePreviewHandler. We use a list instead of a handler manager for efficiency and because we want to fire the handlers in reverse order. When the last handler is removed, handlers is reset to null.

    • Constructor Detail

      • Event

        protected Event()
        Not directly instantiable. Subclasses should also define a protected no-arg constructor to prevent client code from directly instantiating the class.

    • Method Detail

      • addEventPreview

        @Deprecated
public static void addEventPreview​(EventPreview preview)
        Deprecated.
        replaced by addNativePreviewHandler(NativePreviewHandler)
        Adds an event preview to the preview stack. As long as this preview remains on the top of the stack, it will receive all events before they are fired to their listeners. Note that the event preview will receive all events, including those received due to bubbling, whereas normal event handlers only receive explicitly sunk events.
        Parameters:
        preview - the event preview to be added to the stack.

      • as

        public static Event as​(NativeEvent event)
        Converts the NativeEvent to Event. This is always safe.
        Parameters:
        event - the event to downcast

      • fireNativePreviewEvent

        public static boolean fireNativePreviewEvent​(NativeEvent nativeEvent)
        Fire a Event.NativePreviewEvent for the native event.
        Parameters:
        nativeEvent - the native event
        Returns:
        true to fire the event normally, false to cancel the event

      • getCurrentEvent

        public static Event getCurrentEvent()
        Gets the current event that is being fired. The current event is only available within the lifetime of the onBrowserEvent function. Once the onBrowserEvent method returns, the current event is reset to null.
        Returns:
        the current event

      • getEventListener

        public static EventListener getEventListener​(Element elem)
        Gets the EventListener that will receive events for the given element. Only one such listener may exist for a single element.
        Parameters:
        elem - the element whose listener is to be set
        Returns:
        the element's event listener

      • getEventsSunk

        public static int getEventsSunk​(Element elem)
        Gets the current set of events sunk by a given element.
        Parameters:
        elem - the element whose events are to be retrieved
        Returns:
        a bitfield describing the events sunk on this element (its possible values are described in Event)

      • getTypeInt

        public static int getTypeInt​(java.lang.String typeName)
        Gets the enumerated type of this event given a valid event type name.
        Parameters:
        typeName - the typeName to be tested
        Returns:
        the event's enumerated type, or -1 if not defined

      • releaseCapture

        public static void releaseCapture​(Element elem)
        Releases mouse capture on the given element. Calling this method has no effect if the element does not currently have mouse capture.
        Parameters:
        elem - the element to release capture
        See Also:
        setCapture(Element)

      • removeEventPreview

        @Deprecated
public static void removeEventPreview​(EventPreview preview)
        Deprecated.
        use HandlerRegistration returned from addNativePreviewHandler(NativePreviewHandler)
        Removes an element from the preview stack. This element will no longer capture events, though any preview underneath it will begin to do so.
        Parameters:
        preview - the event preview to be removed from the stack

      • setCapture

        public static void setCapture​(Element elem)
        Sets mouse-capture on the given element. This element will directly receive all mouse events until releaseCapture(Element) is called on it.
        Parameters:
        elem - the element on which to set mouse capture

      • setEventListener

        public static void setEventListener​(Element elem,
                                    EventListener listener)
        Sets the EventListener to receive events for the given element. Only one such listener may exist for a single element.
        Parameters:
        elem - the element whose listener is to be set
        listener - the listener to receive events

      • sinkEvents

        public static void sinkEvents​(Element elem,
                              int eventBits)
        Sets the current set of events sunk by a given element. These events will be fired to the nearest EventListener specified on any of the element's parents.
        Parameters:
        elem - the element whose events are to be retrieved
        eventBits - a bitfield describing the events sunk on this element (its possible values are described in Event)

      • cancelBubble

        @Deprecated
public final void cancelBubble​(boolean cancel)
        Deprecated.
        use NativeEvent.stopPropagation() instead
        Cancels bubbling for the given event. This will stop the event from being propagated to parent elements.
        Parameters:
        cancel - true to cancel bubbling

      • getCurrentTarget

        @Deprecated
public final Element getCurrentTarget()
        Deprecated.
        use NativeEvent.getCurrentEventTarget() instead
        Gets the current target element of this event. This is the element whose listener fired last, not the element which fired the event initially.
        Returns:
        the event's current target element

      • getFromElement

        @Deprecated
public final Element getFromElement()
        Deprecated.
        use NativeEvent.getRelatedEventTarget() instead
        Gets the element from which the mouse pointer was moved (only valid for ONMOUSEOVER).
        Returns:
        the element from which the mouse pointer was moved

      • getRepeat

        @Deprecated
public final boolean getRepeat()
        Deprecated.
        not supported on all browsers
        Gets the key-repeat state of this event.
        Returns:
        true if this key event was an auto-repeat

      • getTarget

        @Deprecated
public final Element getTarget()
        Deprecated.
        use NativeEvent.getEventTarget() instead
        Returns the element that was the actual target of the given event.
        Returns:
        the target element

      • getToElement

        @Deprecated
public final Element getToElement()
        Deprecated.
        use NativeEvent.getRelatedEventTarget() instead
        Gets the element to which the mouse pointer was moved (only valid for ONMOUSEOUT).
        Returns:
        the element to which the mouse pointer was moved

      • getTypeInt

        public final int getTypeInt()
        Gets the enumerated type of this event, as defined by ONCLICK, ONMOUSEDOWN, and so forth.
        Returns:
        the event's enumerated type