This method should be only called when the view's container * is valid. Naturally that would be the setParent() method however * that method is not overridden in the RI and that is why we chose * paint() instead.
*/ private void checkContainer() { Container c = getContainer(); if (c instanceof JTextField) { horizontalVisibility = ((JTextField) c).getHorizontalVisibility(); // Provokes a repaint when the BoundedRangeModel's values change // (which is what the RI does). horizontalVisibility.addChangeListener(new ChangeListener(){ public void stateChanged(ChangeEvent event) { getContainer().repaint(); } }); // It turned out that the span calculated at this point is wrong // and needs to be recalculated (e.g. a different font setting is // not taken into account). calculateHorizontalSpan(); // Initializes the BoundedRangeModel properly. updateVisibility(); } } private void updateVisibility() { JTextField tf = (JTextField) getContainer(); Insets insets = tf.getInsets(); int width = tf.getWidth() - insets.left - insets.right; horizontalVisibility.setMaximum(Math.max((int) ((cachedSpan != -1f) ? cachedSpan : calculateHorizontalSpan()), width)); horizontalVisibility.setExtent(width - 1); } protected FontMetrics getFontMetrics() { Component container = getContainer(); return container.getFontMetrics(container.getFont()); } /** * Vertically centers the single line of text within the * bounds of the input shape. The returned Rectangle is centered * vertically withinshape and has a height of the
* preferred span along the Y axis. Horizontal adjustment is done according
* to the horizontalAligment property of the component that is rendered.
*
* @param shape the shape within which the line is beeing centered
*/
protected Shape adjustAllocation(Shape shape)
{
// Return null when the original allocation is null (like the RI).
if (shape == null)
return null;
Rectangle rectIn = shape.getBounds();
// vertical adjustment
int height = (int) getPreferredSpan(Y_AXIS);
int y = rectIn.y + (rectIn.height - height) / 2;
// horizontal adjustment
JTextField textField = (JTextField) getContainer();
int width = (int) ((cachedSpan != -1f) ? cachedSpan : calculateHorizontalSpan());
int x;
if (horizontalVisibility != null && horizontalVisibility.getExtent() < width)
x = rectIn.x - horizontalVisibility.getValue();
else
switch (textField.getHorizontalAlignment())
{
case JTextField.CENTER:
x = rectIn.x + (rectIn.width - width) / 2;
break;
case JTextField.RIGHT:
x = rectIn.x + (rectIn.width - width - 1);
break;
case JTextField.TRAILING:
if (textField.getComponentOrientation().isLeftToRight())
x = rectIn.x + (rectIn.width - width - 1);
else
x = rectIn.x;
break;
case JTextField.LEADING:
if (textField.getComponentOrientation().isLeftToRight())
x = rectIn.x;
else
x = rectIn.x + (rectIn.width - width - 1);
break;
case JTextField.LEFT:
default:
x = rectIn.x;
break;
}
return new Rectangle(x, y, width, height);
}
public float getPreferredSpan(int axis)
{
if (axis != X_AXIS && axis != Y_AXIS)
throw new IllegalArgumentException();
if (axis == Y_AXIS)
return super.getPreferredSpan(axis);
if (cachedSpan != -1f)
return cachedSpan;
return calculateHorizontalSpan();
}
/** Calculates and sets the horizontal span and stores the value
* in cachedSpan.
*/
private float calculateHorizontalSpan()
{
Segment s = getLineBuffer();
Element elem = getElement();
try
{
elem.getDocument().getText(elem.getStartOffset(),
elem.getEndOffset() - 1,
s);
return cachedSpan = Utilities.getTabbedTextWidth(s, getFontMetrics(), 0, this, s.offset);
}
catch (BadLocationException e)
{
// Should never happen
AssertionError ae = new AssertionError();
ae.initCause(e);
throw ae;
}
}
public int getResizeWeight(int axis)
{
return axis == X_AXIS ? 1 : 0;
}
public Shape modelToView(int pos, Shape a, Position.Bias bias)
throws BadLocationException
{
Shape newAlloc = adjustAllocation(a);
return super.modelToView(pos, newAlloc, bias);
}
public void paint(Graphics g, Shape s)
{
if (horizontalVisibility == null)
checkContainer();
Shape newAlloc = adjustAllocation(s);
Shape clip = g.getClip();
if (clip != null)
{
// Reason for this: The allocation area is always determined by the
// size of the component (and its insets) regardless of whether
// parts of the component are invisible or not (e.g. when the
// component is part of a JScrollPane and partly moved out of
// the user-visible range). However the clip of the Graphics
// instance may be adjusted properly to that condition but
// does not handle insets. By calculating the intersection
// we get the correct clip to paint the text in all cases.
Rectangle r = s.getBounds();
Rectangle cb = clip.getBounds();
SwingUtilities.computeIntersection(r.x, r.y, r.width, r.height, cb);
g.setClip(cb);
}
else
g.setClip(s);
super.paint(g, newAlloc);
g.setClip(clip);
}
public void insertUpdate(DocumentEvent ev, Shape shape, ViewFactory vf)
{
cachedSpan = -1f;
if (horizontalVisibility != null)
updateVisibility();
Shape newAlloc = adjustAllocation(shape);
super.insertUpdate(ev, newAlloc, vf);
getContainer().repaint();
}
public void removeUpdate(DocumentEvent ev, Shape shape, ViewFactory vf)
{
cachedSpan = -1f;
if (horizontalVisibility != null)
updateVisibility();
Shape newAlloc = adjustAllocation(shape);
super.removeUpdate(ev, newAlloc, vf);
getContainer().repaint();
}
public void changedUpdate(DocumentEvent ev, Shape shape, ViewFactory vf)
{
cachedSpan = -1f;
if (horizontalVisibility != null)
updateVisibility();
Shape newAlloc = adjustAllocation(shape);
super.changedUpdate(ev, newAlloc, vf);
getContainer().repaint();
}
public int viewToModel(float fx, float fy, Shape a, Position.Bias[] bias)
{
return super.viewToModel(fx, fy, adjustAllocation(a), bias);
}
}