/* * Copyright (c) 1997, 2005, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * 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 * or visit www.oracle.com if you need additional information or have any * questions. */package javax.swing.text; import java.awt.*;import javax.swing.*;import javax.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 */public class FieldView extends PlainView {     /**     * Constructs a new FieldView wrapped on an element.     *     * @param elem the element     */    public FieldView(Element elem) {        super(elem);    }     /**     * Fetches the font metrics associated with the component hosting     * this view.     *     * @return the metrics     */    protected FontMetrics getFontMetrics() {        Component c = getContainer();        return c.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.     */    protected Shape adjustAllocation(Shape a) {        if (a != null) {            Rectangle bounds = a.getBounds();            int vspan = (int) getPreferredSpan(Y_AXIS);            int hspan = (int) getPreferredSpan(X_AXIS);            if (bounds.height != vspan) {                int slop = bounds.height - vspan;                bounds.y += slop / 2;                bounds.height -= slop;            }             // horizontal adjustments            Component c = getContainer();            if (c instanceof JTextField) {                JTextField field = (JTextField) c;                BoundedRangeModel vis = field.getHorizontalVisibility();                int max = Math.max(hspan, bounds.width);                int value = vis.getValue();                int extent = 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                    int slop = bounds.width - 1 - hspan;                     int align = ((JTextField)c).getHorizontalAlignment();                    if(Utilities.isLeftToRight(c)) {                        if(align==LEADING) {                            align = LEFT;                        }                        else if(align==TRAILING) {                            align = RIGHT;                        }                    }                    else {                        if(align==LEADING) {                            align = RIGHT;                        }                        else if(align==TRAILING) {                            align = LEFT;                        }                    }                     switch (align) {                    case SwingConstants.CENTER:                        bounds.x += slop / 2;                        bounds.width -= slop;                        break;                    case SwingConstants.RIGHT:                        bounds.x += slop;                        bounds.width -= slop;                        break;                    }                } else {                    // adjust the allocation to match the bounded range.                    bounds.width = hspan;                    bounds.x -= vis.getValue();                }            }            return bounds;        }        return null;    }     /**     * 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.     */    void updateVisibilityModel() {        Component c = getContainer();        if (c instanceof JTextField) {            JTextField field = (JTextField) c;            BoundedRangeModel vis = field.getHorizontalVisibility();            int hspan = (int) getPreferredSpan(X_AXIS);            int extent = vis.getExtent();            int maximum = Math.max(hspan, extent);            extent = (extent == 0) ? maximum : extent;            int value = maximum - extent;            int oldValue = 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     */    public void paint(Graphics g, Shape a) {        Rectangle r = (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.     */    Shape adjustPaintRegion(Shape a) {        return adjustAllocation(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 >= 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.     */    public float getPreferredSpan(int axis) {        switch (axis) {        case View.X_AXIS:            Segment buff = SegmentCache.getSharedSegment();            Document doc = getDocument();            int width;            try {                FontMetrics fm = getFontMetrics();                doc.getText(0, doc.getLength(), buff);                width = Utilities.getTabbedTextWidth(buff, fm, 0, this, 0);                if (buff.count > 0) {                    Component c = getContainer();                    firstLineOffset = sun.swing.SwingUtilities2.                        getLeftSideBearing((c instanceof JComponent) ?                                           (JComponent)c : null, fm,                                           buff.array[buff.offset]);                    firstLineOffset = Math.max(0, -firstLineOffset);                }                else {                    firstLineOffset = 0;                }            } catch (BadLocationException bl) {                width = 0;            }            SegmentCache.releaseSharedSegment(buff);            return width + firstLineOffset;        default:            return super.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 -> 1 for View.X_AXIS, else 0     */    public int getResizeWeight(int axis) {        if (axis == View.X_AXIS) {            return 1;        }        return 0;    }     /**     * 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 >= 0     * @param a the allocated region to render into     * @return the bounding box of the given position     * @exception BadLocationException  if the given position does not     *   represent a valid location in the associated document     * @see View#modelToView     */    public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException {        return super.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 >= 0.0f     * @param fy the Y coordinate >= 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     */    public int viewToModel(float fx, float fy, Shape a, Position.Bias[] bias) {        return super.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     */    public void insertUpdate(DocumentEvent changes, Shape a, ViewFactory f) {        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     */    public void removeUpdate(DocumentEvent changes, Shape a, ViewFactory f) {        super.removeUpdate(changes, adjustAllocation(a), f);        updateVisibilityModel();    } }