FieldView.java

/*
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation. Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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packagejavax.swing.text;

importjava.awt.*;
importjavax.swing.*;
importjavax.swing.event.*;

/**
 * Extends the multi-line plain text view to be suitable
 * for a single-line editor view. If the view is
 * allocated extra space, the field must adjust for it.
 * If the hosting component is a JTextField, this view
 * will manage the ranges of the associated BoundedRangeModel
 * and will adjust the horizontal allocation to match the
 * current visibility settings of the JTextField.
 *
 * @author Timothy Prinzing
 * @see View
 */
publicclassFieldViewextendsPlainView {

/**
 * Constructs a new FieldView wrapped on an element.
 *
 * @param elem the element
 */
publicFieldView(Elementelem) {
super(elem);
 }

/**
 * Fetches the font metrics associated with the component hosting
 * this view.
 *
 * @return the metrics
 */
protectedFontMetricsgetFontMetrics() {
Componentc = getContainer();
returnc.getFontMetrics(c.getFont());
 }

/**
 * Adjusts the allocation given to the view
 * to be a suitable allocation for a text field.
 * If the view has been allocated more than the
 * preferred span vertically, the allocation is
 * changed to be centered vertically. Horizontally
 * the view is adjusted according to the horizontal
 * alignment property set on the associated JTextField
 * (if that is the type of the hosting component).
 *
 * @param a the allocation given to the view, which may need
 * to be adjusted.
 * @return the allocation that the superclass should use.
 */
protectedShapeadjustAllocation(Shapea) {
if (a != null) {
Rectanglebounds = a.getBounds();
intvspan = (int) getPreferredSpan(Y_AXIS);
inthspan = (int) getPreferredSpan(X_AXIS);
if (bounds.height != vspan) {
intslop = bounds.height - vspan;
bounds.y += slop / 2;
bounds.height -= slop;
 }

// horizontal adjustments
Componentc = getContainer();
if (cinstanceofJTextField) {
JTextFieldfield = (JTextField) c;
BoundedRangeModelvis = field.getHorizontalVisibility();
intmax = Math.max(hspan, bounds.width);
intvalue = vis.getValue();
intextent = Math.min(max, bounds.width - 1);
if ((value + extent) > max) {
value = max - extent;
 }
vis.setRangeProperties(value, extent, vis.getMinimum(),
max, false);
if (hspan < bounds.width) {
// horizontally align the interior
intslop = bounds.width - 1 - hspan;

intalign = ((JTextField)c).getHorizontalAlignment();
if(Utilities.isLeftToRight(c)) {
if(align==LEADING) {
align = LEFT;
 }
elseif(align==TRAILING) {
align = RIGHT;
 }
 }
else {
if(align==LEADING) {
align = RIGHT;
 }
elseif(align==TRAILING) {
align = LEFT;
 }
 }

switch (align) {
caseSwingConstants.CENTER:
bounds.x += slop / 2;
bounds.width -= slop;
break;
caseSwingConstants.RIGHT:
bounds.x += slop;
bounds.width -= slop;
break;
 }
 } else {
// adjust the allocation to match the bounded range.
bounds.width = hspan;
bounds.x -= vis.getValue();
 }
 }
returnbounds;
 }
returnnull;
 }

/**
 * Update the visibility model with the associated JTextField
 * (if there is one) to reflect the current visibility as a
 * result of changes to the document model. The bounded
 * range properties are updated. If the view hasn't yet been
 * shown the extent will be zero and we just set it to be full
 * until determined otherwise.
 */
voidupdateVisibilityModel() {
Componentc = getContainer();
if (cinstanceofJTextField) {
JTextFieldfield = (JTextField) c;
BoundedRangeModelvis = field.getHorizontalVisibility();
inthspan = (int) getPreferredSpan(X_AXIS);
intextent = vis.getExtent();
intmaximum = Math.max(hspan, extent);
extent = (extent == 0) ? maximum : extent;
intvalue = maximum - extent;
intoldValue = vis.getValue();
if ((oldValue + extent) > maximum) {
oldValue = maximum - extent;
 }
value = Math.max(0, Math.min(value, oldValue));
vis.setRangeProperties(value, extent, 0, maximum, false);
 }
 }

// --- View methods -------------------------------------------

/**
 * Renders using the given rendering surface and area on that surface.
 * The view may need to do layout and create child views to enable
 * itself to render into the given allocation.
 *
 * @param g the rendering surface to use
 * @param a the allocated region to render into
 *
 * @see View#paint
 */
publicvoidpaint(Graphicsg, Shapea) {
Rectangler = (Rectangle) a;
g.clipRect(r.x, r.y, r.width, r.height);
super.paint(g, a);
 }

/**
 * Adjusts <code>a</code> based on the visible region and returns it.
 */
ShapeadjustPaintRegion(Shapea) {
returnadjustAllocation(a);
 }

/**
 * Determines the preferred span for this view along an
 * axis.
 *
 * @param axis may be either View.X_AXIS or View.Y_AXIS
 * @return the span the view would like to be rendered into &gt;= 0.
 * Typically the view is told to render into the span
 * that is returned, although there is no guarantee.
 * The parent may choose to resize or break the view.
 */
@SuppressWarnings("deprecation")
publicfloatgetPreferredSpan(intaxis) {
switch (axis) {
caseView.X_AXIS:
Segmentbuff = SegmentCache.getSharedSegment();
Documentdoc = getDocument();
intwidth;
try {
FontMetricsfm = getFontMetrics();
doc.getText(0, doc.getLength(), buff);
width = Utilities.getTabbedTextWidth(buff, fm, 0, this, 0);
if (buff.count > 0) {
Componentc = getContainer();
firstLineOffset = sun.swing.SwingUtilities2.
getLeftSideBearing((cinstanceofJComponent) ?
 (JComponent)c : null, fm,
buff.array[buff.offset]);
firstLineOffset = Math.max(0, -firstLineOffset);
 }
else {
firstLineOffset = 0;
 }
 } catch (BadLocationExceptionbl) {
width = 0;
 }
SegmentCache.releaseSharedSegment(buff);
returnwidth + firstLineOffset;
default:
returnsuper.getPreferredSpan(axis);
 }
 }

/**
 * Determines the resizability of the view along the
 * given axis. A value of 0 or less is not resizable.
 *
 * @param axis View.X_AXIS or View.Y_AXIS
 * @return the weight -&gt; 1 for View.X_AXIS, else 0
 */
publicintgetResizeWeight(intaxis) {
if (axis == View.X_AXIS) {
return1;
 }
return0;
 }

/**
 * Provides a mapping from the document model coordinate space
 * to the coordinate space of the view mapped to it.
 *
 * @param pos the position to convert &gt;= 0
 * @param a the allocated region to render into
 * @return the bounding box of the given position
 * @throws BadLocationException if the given position does not
 * represent a valid location in the associated document
 * @see View#modelToView
 */
publicShapemodelToView(intpos, Shapea, Position.Biasb) throwsBadLocationException {
returnsuper.modelToView(pos, adjustAllocation(a), b);
 }

/**
 * Provides a mapping from the view coordinate space to the logical
 * coordinate space of the model.
 *
 * @param fx the X coordinate &gt;= 0.0f
 * @param fy the Y coordinate &gt;= 0.0f
 * @param a the allocated region to render into
 * @return the location within the model that best represents the
 * given point in the view
 * @see View#viewToModel
 */
publicintviewToModel(floatfx, floatfy, Shapea, Position.Bias[] bias) {
returnsuper.viewToModel(fx, fy, adjustAllocation(a), bias);
 }

/**
 * Gives notification that something was inserted into the document
 * in a location that this view is responsible for.
 *
 * @param changes the change information from the associated document
 * @param a the current allocation of the view
 * @param f the factory to use to rebuild if the view has children
 * @see View#insertUpdate
 */
publicvoidinsertUpdate(DocumentEventchanges, Shapea, ViewFactoryf) {
super.insertUpdate(changes, adjustAllocation(a), f);
updateVisibilityModel();
 }

/**
 * Gives notification that something was removed from the document
 * in a location that this view is responsible for.
 *
 * @param changes the change information from the associated document
 * @param a the current allocation of the view
 * @param f the factory to use to rebuild if the view has children
 * @see View#removeUpdate
 */
publicvoidremoveUpdate(DocumentEventchanges, Shapea, ViewFactoryf) {
super.removeUpdate(changes, adjustAllocation(a), f);
updateVisibilityModel();
 }

}