jscrollbar.java

gcc的组建

   *
   * @param unitIncrement The new unitIncrement.
   */
  public void setUnitIncrement(int unitIncrement)
  {
    if (unitIncrement != this.unitIncrement)
      {
	int oldInc = this.unitIncrement;
	this.unitIncrement = unitIncrement;
	firePropertyChange("unitIncrement", oldInc,
	                   this.unitIncrement);
      }
  }

  /**
   * The method returns how much the scrollbar's value
   * should change for a block increment depending on
   * the given direction.
   *
   * @param direction The direction to scroll in.
   *
   * @return The amount the scrollbar's value will change given the direction.
   */
  public int getBlockIncrement(int direction)
  {
    return direction * blockIncrement;
  }

  /**
   * This method sets the blockIncrement property.
   *
   * @param blockIncrement The new blockIncrement.
   */
  public void setBlockIncrement(int blockIncrement)
  {
    if (blockIncrement != this.blockIncrement)
      {
	int oldInc = this.blockIncrement;
	this.blockIncrement = blockIncrement;
	firePropertyChange("blockIncrement", oldInc,
	                   this.blockIncrement);
      }
  }

  /**
   * This method returns the unitIncrement.
   *
   * @return The unitIncrement.
   */
  public int getUnitIncrement()
  {
    return unitIncrement;
  }

  /**
   * This method returns the blockIncrement.
   *
   * @return The blockIncrement.
   */
  public int getBlockIncrement()
  {
    return blockIncrement;
  }

  /**
   * This method returns the value of the scrollbar.
   *
   * @return The value of the scrollbar.
   */
  public int getValue()
  {
    return model.getValue();
  }

  /**
   * This method changes the value of the scrollbar.
   *
   * @param value The new value of the scrollbar.
   */
  public void setValue(int value)
  {
    if (isEnabled() && value != getValue())
    {
      model.setValue(value);
      fireAdjustmentValueChanged(AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED,
                                 AdjustmentEvent.TRACK, value);
    }
  }

  /**
   * This method returns the visible amount (AKA extent). 
   * The visible amount can be used by UI delegates to 
   * determine the size of the thumb.
   *
   * @return The visible amount (AKA extent).
   */
  public int getVisibleAmount()
  {
    return model.getExtent();
  }

  /**
   * This method sets the visible amount (AKA extent).
   *
   * @param extent The visible amount (AKA extent).
   */
  public void setVisibleAmount(int extent)
  {
    if (extent != getVisibleAmount())
    {
      model.setExtent(extent);
      fireAdjustmentValueChanged(AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED,
                                 AdjustmentEvent.TRACK, extent);
    }
  }

  /**
   * This method returns the minimum value of the scrollbar.
   *
   * @return The minimum value of the scrollbar.
   */
  public int getMinimum()
  {
    return model.getMinimum();
  }

  /**
   * This method sets the minimum value of the scrollbar.
   *
   * @param minimum The minimum value of the scrollbar.
   */
  public void setMinimum(int minimum)
  {
    if (minimum != getMinimum())
    {
      model.setMinimum(minimum);
      fireAdjustmentValueChanged(AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED,
                                 AdjustmentEvent.TRACK, minimum);
    }
  }

  /**
   * This method returns the maximum value of the scrollbar.
   *
   * @return The maximum value of the scrollbar.
   */
  public int getMaximum()
  {
    return model.getMaximum();
  }

  /**
   * This method sets the maximum value of the scrollbar.
   *
   * @param maximum The maximum value of the scrollbar.
   */
  public void setMaximum(int maximum)
  {
    if (maximum != getMaximum())
    {
      model.setMaximum(maximum);
      fireAdjustmentValueChanged(AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED,
                                 AdjustmentEvent.TRACK, maximum);
    }
  }

  /**
   * This method returns the model's isAjusting value.
   *
   * @return The model's isAdjusting value.
   */
  public boolean getValueIsAdjusting()
  {
    return model.getValueIsAdjusting();
  }

  /**
   * This method sets the model's isAdjusting value.
   *
   * @param b The new isAdjusting value.
   */
  public void setValueIsAdjusting(boolean b)
  {
    model.setValueIsAdjusting(b);
  }

  /**
   * This method sets the value, extent, minimum and 
   * maximum.
   *
   * @param newValue The new value.
   * @param newExtent The new extent.
   * @param newMin The new minimum.
   * @param newMax The new maximum.
   */
  public void setValues(int newValue, int newExtent, int newMin, int newMax)
  {
    if (!isEnabled())
      newValue = model.getValue();
    // It seems to be that on any change the value is fired.
    if (newValue != getValue() || newExtent != getVisibleAmount() ||
        newMin != getMinimum() || newMax != getMaximum())
    {
      model.setRangeProperties(newValue, newExtent, newMin, newMax,
                               model.getValueIsAdjusting());
      fireAdjustmentValueChanged(AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED,
                                 AdjustmentEvent.TRACK, newValue);
    }
  }

  /**
   * This method adds an AdjustmentListener to the scroll bar.
   *
   * @param listener The listener to add.
   */
  public void addAdjustmentListener(AdjustmentListener listener)
  {
    listenerList.add(AdjustmentListener.class, listener);
  }

  /**
   * This method removes an AdjustmentListener from the scroll bar. 
   *
   * @param listener The listener to remove.
   */
  public void removeAdjustmentListener(AdjustmentListener listener)
  {
    listenerList.remove(AdjustmentListener.class, listener);
  }

  /**
   * This method returns an arry of all AdjustmentListeners listening to 
   * this scroll bar.
   *
   * @return An array of AdjustmentListeners listening to this scroll bar.
   */
  public AdjustmentListener[] getAdjustmentListeners()
  {
    return (AdjustmentListener[]) listenerList.getListeners(AdjustmentListener.class);
  }

  /**
   * This method is called to fired AdjustmentEvents to the listeners
   * of this scroll bar. All AdjustmentEvents that are fired
   * will have an ID of ADJUSTMENT_VALUE_CHANGED and a type of
   * TRACK. 
   *
   * @param id The ID of the adjustment event.
   * @param type The Type of change.
   * @param value The new value for the property that was changed..
   */
  protected void fireAdjustmentValueChanged(int id, int type, int value)
  {
    Object[] adjustmentListeners = listenerList.getListenerList();
    AdjustmentEvent adjustmentEvent = new AdjustmentEvent(this, 
                                            AdjustmentEvent.ADJUSTMENT_VALUE_CHANGED,
					    AdjustmentEvent.TRACK,
					    value);
    for (int i = adjustmentListeners.length - 2; i >= 0; i -= 2)
      {
	if (adjustmentListeners[i] == AdjustmentListener.class)
	  ((AdjustmentListener) adjustmentListeners[i + 1]).adjustmentValueChanged(adjustmentEvent);
      }
  }

  /**
   * This method returns the minimum size for this scroll bar.
   *
   * @return The minimum size.
   */
  public Dimension getMinimumSize()
  {
    return ui.getMinimumSize(this);
  }

  /**
   * This method returns the maximum size for this scroll bar.
   *
   * @return The maximum size.
   */
  public Dimension getMaximumSize()
  {
    return ui.getMaximumSize(this);
  }

  /**
   * This method overrides the setEnabled in JComponent.
   * When the scroll bar is disabled, the knob cannot
   * be moved.
   *
   * @param x Whether the scrollbar is enabled.
   */
  public void setEnabled(boolean x)
  {
    // nothing special needs to be done here since we 
    // just check the enabled setting before changing the value.
    super.setEnabled(x);
  }

  /**
   * A string that describes this JScrollBar. Normally only used
   * for debugging.
   *
   * @return A string describing this JScrollBar.
   */
  protected String paramString()
  {
    return "JScrollBar";
  }

  /**
   * DOCUMENT ME!
   *
   * @return DOCUMENT ME!
   */
  public AccessibleContext getAccessibleContext()
  {
    if (accessibleContext == null)
      accessibleContext = new AccessibleJScrollBar();
    return accessibleContext;
  }
}