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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
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 * particular file as subject to the "Classpath" exception as provided
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 *
 * 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).
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 *
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package javax.swing.plaf.basic;

import java.awt.*;
import java.awt.event.KeyEvent;
import java.awt.event.FocusEvent;
import java.awt.event.InputEvent;
import java.beans.PropertyChangeEvent;
import java.io.Reader;
import javax.swing.*;
import javax.swing.border.*;
import javax.swing.event.*;
import javax.swing.text.*;
import javax.swing.plaf.*;
import sun.swing.DefaultLookup;


Basis of a look and feel for a JTextField.


Warning:
Serialized objects of this class will not be compatible with
future Swing releases. The current serialization support is
appropriate for short term storage or RMI between applications running
the same version of Swing.  As of 1.4, support for long term storage
of all JavaBeans™
has been added to the java.beans package. Please see XMLEncoder. 
Author: Timothy Prinzing
/**
 * Basis of a look and feel for a JTextField.
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @author  Timothy Prinzing
 */
public class BasicTextFieldUI extends BasicTextUI {

    
Creates a UI for a JTextField.

Params:
  • c – the text field
Returns:the UI
/**
     * Creates a UI for a JTextField.
     *
     * @param c the text field
     * @return the UI
     */
    public static ComponentUI createUI(JComponent c) {
        return new BasicTextFieldUI();
    }

    
Creates a new BasicTextFieldUI.

/**
     * Creates a new BasicTextFieldUI.
     */
    public BasicTextFieldUI() {
        super();
    }

    
Fetches the name used as a key to lookup properties through the
UIManager.  This is used as a prefix to all the standard
text properties.

Returns:the name ("TextField")
/**
     * Fetches the name used as a key to lookup properties through the
     * UIManager.  This is used as a prefix to all the standard
     * text properties.
     *
     * @return the name ("TextField")
     */
    protected String getPropertyPrefix() {
        return "TextField";
    }

    
Creates a view (FieldView) based on an element.

Params:
  • elem – the element
Returns:the view
/**
     * Creates a view (FieldView) based on an element.
     *
     * @param elem the element
     * @return the view
     */
    public View create(Element elem) {
        Document doc = elem.getDocument();
        Object i18nFlag = doc.getProperty("i18n"/*AbstractDocument.I18NProperty*/);
        if (Boolean.TRUE.equals(i18nFlag)) {
            // To support bidirectional text, we build a more heavyweight
            // representation of the field.
            String kind = elem.getName();
            if (kind != null) {
                if (kind.equals(AbstractDocument.ContentElementName)) {
                    return new GlyphView(elem){
                        @Override
                        public float getMinimumSpan(int axis) {
                            // no wrap
                            return getPreferredSpan(axis);
                        }
                    };
                } else if (kind.equals(AbstractDocument.ParagraphElementName)) {
                    return new I18nFieldView(elem);
                }
            }
            // this shouldn't happen, should probably throw in this case.
        }
        return new FieldView(elem);
    }

    
Returns the baseline.

Throws:
See Also:
Since:1.6
/**
     * Returns the baseline.
     *
     * @throws NullPointerException {@inheritDoc}
     * @throws IllegalArgumentException {@inheritDoc}
     * @see javax.swing.JComponent#getBaseline(int, int)
     * @since 1.6
     */
    public int getBaseline(JComponent c, int width, int height) {
        super.getBaseline(c, width, height);
        View rootView = getRootView((JTextComponent)c);
        if (rootView.getViewCount() > 0) {
            Insets insets = c.getInsets();
            height = height - insets.top - insets.bottom;
            if (height > 0) {
                int baseline = insets.top;
                View fieldView = rootView.getView(0);
                int vspan = (int)fieldView.getPreferredSpan(View.Y_AXIS);
                if (height != vspan) {
                    int slop = height - vspan;
                    baseline += slop / 2;
                }
                if (fieldView instanceof I18nFieldView) {
                    int fieldBaseline = BasicHTML.getBaseline(
                            fieldView, width - insets.left - insets.right,
                            height);
                    if (fieldBaseline < 0) {
                        return -1;
                    }
                    baseline += fieldBaseline;
                }
                else {
                    FontMetrics fm = c.getFontMetrics(c.getFont());
                    baseline += fm.getAscent();
                }
                return baseline;
            }
        }
        return -1;
    }

    
Returns an enum indicating how the baseline of the component
changes as the size changes.

Throws:
  • NullPointerException – {@inheritDoc}
See Also:
Since:1.6
/**
     * Returns an enum indicating how the baseline of the component
     * changes as the size changes.
     *
     * @throws NullPointerException {@inheritDoc}
     * @see javax.swing.JComponent#getBaseline(int, int)
     * @since 1.6
     */
    public Component.BaselineResizeBehavior getBaselineResizeBehavior(
            JComponent c) {
        super.getBaselineResizeBehavior(c);
        return Component.BaselineResizeBehavior.CENTER_OFFSET;
    }


    
A field view that support bidirectional text via the
support provided by ParagraphView.

/**
     * A field view that support bidirectional text via the
     * support provided by ParagraphView.
     */
    static class I18nFieldView extends ParagraphView {

        I18nFieldView(Element elem) {
            super(elem);
        }

        
Fetch the constraining span to flow against for
the given child index.  There is no limit for
a field since it scrolls, so this is implemented to
return Integer.MAX_VALUE.

/**
         * Fetch the constraining span to flow against for
         * the given child index.  There is no limit for
         * a field since it scrolls, so this is implemented to
         * return <code>Integer.MAX_VALUE</code>.
         */
        public int getFlowSpan(int index) {
            return Integer.MAX_VALUE;
        }

        protected void setJustification(int j) {
            // Justification is done in adjustAllocation(), so disable
            // ParagraphView's justification handling by doing nothing here.
        }

        static boolean isLeftToRight( java.awt.Component c ) {
            return c.getComponentOrientation().isLeftToRight();
        }

        
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).

Params:
  • a – the allocation given to the view, which may need
 to be adjusted.
Returns:the allocation that the superclass should use.
/**
         * 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.
         */
        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(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.

/**
         * 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.

Params:
  • g – the rendering surface to use
  • a – the allocated region to render into
See Also:
/**
         * 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, adjustAllocation(a));
        }

        
Determines the resizability of the view along the
given axis.  A value of 0 or less is not resizable.

Params:
  • axis – View.X_AXIS or View.Y_AXIS
Returns:the weight -> 1 for View.X_AXIS, else 0
/**
         * 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.

Params:
  • pos – the position to convert >= 0
  • a – the allocated region to render into
Throws:
  • BadLocationException –  if the given position does not
  represent a valid location in the associated document
See Also:
Returns:the bounding box of the given position
/**
         * 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 document model coordinate space
to the coordinate space of the view mapped to it.

Params:
  • p0 – the position to convert >= 0
  • b0 – the bias toward the previous character or the
 next character represented by p0, in case the
 position is a boundary of two views.
  • p1 – the position to convert >= 0
  • b1 – the bias toward the previous character or the
 next character represented by p1, in case the
 position is a boundary of two views.
  • a – the allocated region to render into
Throws:
See Also:
Returns:the bounding box of the given position is returned
/**
         * Provides a mapping from the document model coordinate space
         * to the coordinate space of the view mapped to it.
         *
         * @param p0 the position to convert >= 0
         * @param b0 the bias toward the previous character or the
         *  next character represented by p0, in case the
         *  position is a boundary of two views.
         * @param p1 the position to convert >= 0
         * @param b1 the bias toward the previous character or the
         *  next character represented by p1, in case the
         *  position is a boundary of two views.
         * @param a the allocated region to render into
         * @return the bounding box of the given position is returned
         * @exception BadLocationException  if the given position does
         *   not represent a valid location in the associated document
         * @exception IllegalArgumentException for an invalid bias argument
         * @see View#viewToModel
         */
        public Shape modelToView(int p0, Position.Bias b0,
                                 int p1, Position.Bias b1, Shape a)
            throws BadLocationException
        {
            return super.modelToView(p0, b0, p1, b1, adjustAllocation(a));
        }

        
Provides a mapping from the view coordinate space to the logical
coordinate space of the model.

Params:
  • fx – the X coordinate >= 0.0f
  • fy – the Y coordinate >= 0.0f
  • a – the allocated region to render into
See Also:
Returns:the location within the model that best represents the
 given point in the view
/**
         * 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.

Params:
  • changes – the change information from the associated document
  • a – the current allocation of the view
  • f – the factory to use to rebuild if the view has children
See Also:
/**
         * 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.

Params:
  • changes – the change information from the associated document
  • a – the current allocation of the view
  • f – the factory to use to rebuild if the view has children
See Also:
/**
         * 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();
        }

    }

}