Class ScrollbarBundle

Field Detail

• root

  protected final com.google.gwt.dom.client.Element root

  Root element for the scrollbar-composition.

• scrollSizeElement

  protected final com.google.gwt.dom.client.Element scrollSizeElement

  Scroll size element. The size of this element determines the number of pixels the scrollbar is able to scroll through

• isInvisibleScrollbar

  protected boolean isInvisibleScrollbar

  Is the scrollbar "invisible" (thickness set to 0).

Method Detail

• internalGetScrollSize

  protected abstract String internalGetScrollSize()

  Returns the width (for horizontal) or height (for vertical) css property for the scroll size element.

  Returns:

  the relevant size property based on orientation

• setStylePrimaryName

  public void setStylePrimaryName​(String primaryStyleName)

  Sets the primary style name.

  Parameters:

  primaryStyleName - The primary style name to use

• getElement

  public final com.google.gwt.dom.client.Element getElement()

  Gets the root element of this scrollbar-composition.

  Returns:

  the root element

• setScrollPosByDelta

  public final void setScrollPosByDelta​(double delta)

  Modifies the scroll position of this scrollbar by a number of pixels.

  Note: Even though double values are used, they are currently only used as integers as large int (or small but fast long). This means, all values are truncated to zero decimal places.

  Parameters:

  delta - the delta in pixels to change the scroll position by

• internalSetOffsetSize

  protected abstract void internalSetOffsetSize​(double px)

  Modifies root's dimensions in the axis the scrollbar is representing.

  Parameters:

  px - the new size of root in the dimension this scrollbar is representing

• setOffsetSize

  public final void setOffsetSize​(double px)

  Sets the length of the scrollbar.

  Parameters:

  px - the length of the scrollbar in pixels

  See Also:

  setOffsetSizeAndScrollSize(double, double)

• setOffsetSizeAndScrollSize

  public final void setOffsetSizeAndScrollSize​(double offsetPx,
                                               double scrollPx)

  Sets the length of the scrollbar and the amount of pixels the scrollbar needs to be able to scroll through.

  Parameters:

  offsetPx - the length of the scrollbar in pixels

  scrollPx - the number of pixels the scrollbar should be able to scroll through

• forceScrollbar

  protected void forceScrollbar​(boolean enable)

  Force the scrollbar to be visible with CSS. In practice, this means to set either overflow-x or overflow-y to " scroll" in the scrollbar's direction.

  This method is an IE8 workaround, since it doesn't always show scrollbars with overflow: auto enabled.

  Firefox on the other hand loses pending scroll events when the scrollbar is hidden, so the event must be fired manually.

  When IE8 support is dropped, this should really be simplified.

  Parameters:

  enable - true if the scrollbar should be forced to be visible, false otherwise.

• internalForceScrollbar

  protected abstract void internalForceScrollbar​(boolean enable)

  Sets the overflow-x (for horizontal) or overflow-y (for vertical) property to "scroll" if enabled, or clears the property if disabled.

  Parameters:

  enable - true if the overflow property should be set, false otherwise.

• getOffsetSize

  public double getOffsetSize()

  Gets the length of the scrollbar.

  Returns:

  the length of the scrollbar in pixels

• internalGetOffsetSize

  public abstract String internalGetOffsetSize()

  Returns the width (for horizontal) or height (for vertical) css property for the root element.

  Returns:

  the relevant size property based on orientation

• setScrollPos

  public final void setScrollPos​(double px)

  Sets the scroll position of the scrollbar in the axis the scrollbar is representing.

  Note: Even though double values are used, they are currently only used as integers as large int (or small but fast long). This means, all values are truncated to zero decimal places.

  Parameters:

  px - the new scroll position in pixels

• onLoad

  public void onLoad()

  Should be called whenever this bundle is attached to the DOM (typically, from the onLoad of the containing widget). Used to ensure the DOM scroll position is maintained when detaching and reattaching the bundle.

  Since:

  7.4.1

• internalSetScrollPos

  protected abstract void internalSetScrollPos​(int px)

  Modifies the element's scroll position (scrollTop or scrollLeft).

  Note: The parameter here is a type of integer (instead of a double) by design. The browsers internally convert all double values into an integer value. To make this fact explicit, this API has chosen to force integers already at this level.

  Parameters:

  px - integer pixel value to scroll to

• getScrollPos

  public final double getScrollPos()

  Gets the scroll position of the scrollbar in the axis the scrollbar is representing.

  Returns:

  the new scroll position in pixels

• internalGetScrollPos

  protected abstract int internalGetScrollPos()

  Retrieves the element's scroll position (scrollTop or scrollLeft).

  Note: The parameter here is a type of integer (instead of a double) by design. The browsers internally convert all double values into an integer value. To make this fact explicit, this API has chosen to force integers already at this level.

  Returns:

  integer pixel value of the scroll position

• internalSetScrollSize

  protected abstract void internalSetScrollSize​(double px)

  Modifies scrollSizeElement's dimensions in such a way that the scrollbar is able to scroll a certain number of pixels in the axis it is representing.

  Parameters:

  px - the new size of scrollSizeElement in the dimension this scrollbar is representing

• setScrollSize

  public final void setScrollSize​(double px)

  Sets the amount of pixels the scrollbar needs to be able to scroll through.

  Parameters:

  px - the number of pixels the scrollbar should be able to scroll through

  See Also:

  setOffsetSizeAndScrollSize(double, double)

• getScrollSize

  public double getScrollSize()

  Gets the amount of pixels the scrollbar needs to be able to scroll through.

  Returns:

  the number of pixels the scrollbar should be able to scroll through

• internalSetScrollbarThickness

  protected abstract void internalSetScrollbarThickness​(double px)

  Modifies scrollSizeElement's dimensions in the opposite axis to what the scrollbar is representing.

  Parameters:

  px - the dimension that scrollSizeElement should take in the opposite axis to what the scrollbar is representing

• setScrollbarThickness

  public final void setScrollbarThickness​(double px)

  Sets the scrollbar's thickness.

  If the thickness is set to 0, the scrollbar will be treated as an "invisible" scrollbar. This means, the DOM structure will be given a non-zero size, but getScrollbarThickness() will still return the value 0.

  Parameters:

  px - the scrollbar's thickness in pixels

• internalGetScrollbarThickness

  protected abstract String internalGetScrollbarThickness()

  Gets the scrollbar's thickness as defined in the DOM.

  Returns:

  the scrollbar's thickness as defined in the DOM, in pixels

• getScrollbarThickness

  public final double getScrollbarThickness()

  Gets the scrollbar's thickness.

  This value will differ from the value in the DOM, if the thickness was set to 0 with setScrollbarThickness(double), as the scrollbar is then treated as "invisible."

  Returns:

  the scrollbar's thickness in pixels

• showsScrollHandle

  public boolean showsScrollHandle()

  Checks whether the scrollbar's handle is visible.

  In other words, this method checks whether the contents is larger than can visually fit in the element.

  Returns:

  true if the scrollbar's handle is visible

• recalculateMaxScrollPos

  public void recalculateMaxScrollPos()

  Calculates and sets maximum scroll position based on the current scroll size and the scrollbar's length.

• getHandlerManager

  protected com.google.gwt.event.shared.HandlerManager getHandlerManager()

  Returns the handler manager for this scrollbar bundle.

  Returns:

  the handler manager

• addVisibilityHandler

  public com.google.gwt.event.shared.HandlerRegistration addVisibilityHandler​(ScrollbarBundle.VisibilityHandler handler)

  Adds handler for the scrollbar handle visibility.

  Parameters:

  handler - the ScrollbarBundle.VisibilityHandler to add

  Returns:

  HandlerRegistration used to remove the handler

• setLocked

  public void setLocked​(boolean isLocked)

  Locks or unlocks the scrollbar bundle.

  A locked scrollbar bundle will refuse to scroll, both programmatically and via user-triggered events.

  Parameters:

  isLocked - true to lock, false to unlock

• isLocked

  public boolean isLocked()

  Checks whether the scrollbar bundle is locked or not.

  Returns:

  true if the scrollbar bundle is locked

• getDirection

  public abstract ScrollbarBundle.Direction getDirection()

  Returns the scroll direction of this scrollbar bundle.

  Returns:

  the scroll direction of this scrollbar bundle

• addScrollHandler

  public com.google.gwt.event.shared.HandlerRegistration addScrollHandler​(ScrollHandler handler)

  Adds a scroll handler to the scrollbar bundle.

  Parameters:

  handler - the handler to add

  Returns:

  the registration object for the handler registration

• isWorkPending

  public boolean isWorkPending()

  Description copied from interface: DeferredWorker

  Checks whether there are operations pending for this widget or connector that must be executed before reaching a steady state.

  Specified by:

  isWorkPending in interface DeferredWorker