java.lang.Object
java.util.EventObject
java.awt.AWTEvent
java.awt.event.ComponentEvent
java.awt.event.InputEvent
java.awt.event.MouseEvent
java.awt.event.MouseWheelEvent
- All Implemented Interfaces:
- java.io.Serializable
- public class MouseWheelEvent
- extends MouseEvent
This event is generated for a mouse wheel rotation. The wheel (the middle
mouse button on most modern mice) can be rotated towards or away from the
user, and is often used for scrolling.
Because of the special use for scrolling components, MouseWheelEvents
often affect a different component than the one located at the point of
the event. If the component under the mouse cursor does not accept wheel
events, the event is passed to the first ancestor container which does. This
is often a ScrollPane, which knows how to scroll. If an AWT component is
built from a native widget that knows how to use mouse wheel events, that
component will consume the event.
The two most common scroll types are "units" (lines at a time) or
"blocks" (pages at a time). The initial setting is taken from the platform,
although the user can adjust the setting at any time.
- Since:
- 1.4
| Fields inherited from class java.awt.event.MouseEvent |
BUTTON1, BUTTON2, BUTTON3, MOUSE_CLICKED, MOUSE_DRAGGED, MOUSE_ENTERED, MOUSE_EXITED, MOUSE_FIRST, MOUSE_LAST, MOUSE_MOVED, MOUSE_PRESSED, MOUSE_RELEASED, MOUSE_WHEEL, NOBUTTON |
| Fields inherited from class java.awt.event.InputEvent |
ALT_DOWN_MASK, ALT_GRAPH_DOWN_MASK, ALT_GRAPH_MASK, ALT_MASK, BUTTON1_DOWN_MASK, BUTTON1_MASK, BUTTON2_DOWN_MASK, BUTTON2_MASK, BUTTON3_DOWN_MASK, BUTTON3_MASK, CONVERT_MASK, CTRL_DOWN_MASK, CTRL_MASK, META_DOWN_MASK, META_MASK, modifiers, modifiersEx, SHIFT_DOWN_MASK, SHIFT_MASK |
| Fields inherited from class java.awt.AWTEvent |
ACTION_EVENT_MASK, ADJUSTMENT_EVENT_MASK, COMPONENT_EVENT_MASK, consumed, CONTAINER_EVENT_MASK, FOCUS_EVENT_MASK, HIERARCHY_BOUNDS_EVENT_MASK, HIERARCHY_EVENT_MASK, id, INPUT_METHOD_EVENT_MASK, INVOCATION_EVENT_MASK, ITEM_EVENT_MASK, KEY_EVENT_MASK, MOUSE_EVENT_MASK, MOUSE_MOTION_EVENT_MASK, MOUSE_WHEEL_EVENT_MASK, PAINT_EVENT_MASK, RESERVED_ID_MAX, TEXT_EVENT_MASK, WINDOW_EVENT_MASK, WINDOW_FOCUS_EVENT_MASK, WINDOW_STATE_EVENT_MASK |
|
Constructor Summary |
MouseWheelEvent(java.awt.Component source,
int id,
long when,
int modifiers,
int x,
int y,
int clickCount,
boolean popupTrigger,
int scrollType,
int scrollAmount,
int wheelRotation)
Initializes a new instance of MouseWheelEvent with the
specified information. |
|
Method Summary |
int |
getScrollAmount()
Returns the number of units to scroll in response to this event. |
int |
getScrollType()
This method returns the scrolling pattern this event requests. |
int |
getUnitsToScroll()
This is a convenience method which aids in a common listener for scrolling
a scrollpane (although this is already built into ScrollPane and
JScrollPane). |
int |
getWheelRotation()
Gets the number of "clicks" the wheel was rotated. |
java.lang.String |
paramString()
Returns a string identifying this event. |
| Methods inherited from class java.awt.event.InputEvent |
consume, getModifiers, getModifiersEx, getModifiersExText, getWhen, isAltDown, isAltGraphDown, isConsumed, isControlDown, isMetaDown, isShiftDown |
serialVersionUID
private static final long serialVersionUID
- Compatible with JDK 1.4+.
- See Also:
- Constant Field Values
WHEEL_UNIT_SCROLL
public static final int WHEEL_UNIT_SCROLL
- Indicates scrolling by units (lines).
- See Also:
getScrollType() 55 ,
Constant Field Values
WHEEL_BLOCK_SCROLL
public static final int WHEEL_BLOCK_SCROLL
- Indicates scrolling by blocks (pages).
- See Also:
getScrollType() 55 ,
Constant Field Values
scrollType
private final int scrollType
- Indicates what scroll type should take place. This should be limited
to
WHEEL_UNIT_SCROLL 55 and WHEEL_BLOCK_SCROLL 55 .
scrollAmount
private final int scrollAmount
- Indicates the scroll amount. This is only meaningful if scrollType is
WHEEL_UNIT_SCROLL.
wheelRotation
private final int wheelRotation
- Indicates how far the mouse wheel was rotated.
MouseWheelEvent
public MouseWheelEvent(java.awt.Component source,
int id,
long when,
int modifiers,
int x,
int y,
int clickCount,
boolean popupTrigger,
int scrollType,
int scrollAmount,
int wheelRotation)
- Initializes a new instance of
MouseWheelEvent with the
specified information. Note that an invalid id leads to unspecified
results.
getScrollType
public int getScrollType()
- This method returns the scrolling pattern this event requests. Legal
values are
WHEEL_UNIT_SCROLL 55 and WHEEL_BLOCK_SCROLL 55 .
getScrollAmount
public int getScrollAmount()
- Returns the number of units to scroll in response to this event. This
only makes sense when the scroll type is WHEEL_UNIT_SCROLL.
getWheelRotation
public int getWheelRotation()
- Gets the number of "clicks" the wheel was rotated. Negative values move
up (away) from the user, positive values move down (towards) the user.
getUnitsToScroll
public int getUnitsToScroll()
- This is a convenience method which aids in a common listener for scrolling
a scrollpane (although this is already built into ScrollPane and
JScrollPane). This method only makes sense when getScrollType() returns
WHEEL_UNIT_SCROLL.
This accounts for direction of scroll and amount of wheel movement, as
interpreted by the platform settings.
paramString
public java.lang.String paramString()
- Returns a string identifying this event. For mouse wheel events, this
is
super.paramString() + ",scrollType=WHEEL_" +
(getScrollType() == WHEEL_UNIT_SCROLL ? "UNIT" : "BLOCK")
+ "_SCROLL,scrollAmount=" + getScrollAmount() + ",wheelRotation="
+ getWheelRotation().
- Overrides:
paramString in class MouseEvent
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