basictextui.java

java1.6众多例子参考

     * @param c the editor component
     * @see ComponentUI#installUI
     */
    public void installUI(JComponent c) {
        if (c instanceof JTextComponent) {
            editor = (JTextComponent) c;

            // install defaults
            installDefaults();
            installDefaults2();

            // This is a workaround as these should not override what synth has
            // set them to
            if (!(this instanceof sun.swing.plaf.synth.SynthUI)){
                // common case is background painted... this can
                // easily be changed by subclasses or from outside
                // of the component.
                LookAndFeel.installProperty(editor, "opaque", Boolean.TRUE);
                LookAndFeel.installProperty(editor, "autoscrolls", Boolean.TRUE);
            }

            // attach to the model and editor
            editor.addPropertyChangeListener(updateHandler);
            Document doc = editor.getDocument();
            if (doc == null) {
                // no model, create a default one.  This will
                // fire a notification to the updateHandler 
                // which takes care of the rest. 
                editor.setDocument(getEditorKit(editor).createDefaultDocument());
            } else {
                doc.addDocumentListener(updateHandler);
                modelChanged();
            }

            // install keymap
            installListeners();
            installKeyboardActions();

	    LayoutManager oldLayout = editor.getLayout();
	    if ((oldLayout == null) || (oldLayout instanceof UIResource)) {
		// by default, use default LayoutManger implementation that
		// will position the components associated with a View object.
		editor.setLayout(updateHandler);
	    }

            updateBackground(editor);
        } else {
            throw new Error("TextUI needs JTextComponent");
        }
    }

    /**
     * Deinstalls the UI for a component.  This removes the listeners,
     * uninstalls the highlighter, removes views, and nulls out the keymap.
     *
     * @param c the editor component
     * @see ComponentUI#uninstallUI
     */
    public void uninstallUI(JComponent c) {
        // detach from the model
        editor.removePropertyChangeListener(updateHandler);
        editor.getDocument().removeDocumentListener(updateHandler);

        // view part
        painted = false;
        uninstallDefaults();
        rootView.setView(null);
        c.removeAll();
	LayoutManager lm = c.getLayout();
	if (lm instanceof UIResource) {
	    c.setLayout(null);
	}

        // controller part
        uninstallKeyboardActions();
        uninstallListeners();

        editor = null;
    }

    /**
     * Superclass paints background in an uncontrollable way
     * (i.e. one might want an image tiled into the background).
     * To prevent this from happening twice, this method is
     * reimplemented to simply paint.
     * <p>
     * <em>NOTE:</em> Superclass is also not thread-safe in 
     * it's rendering of the background, although that's not
     * an issue with the default rendering.
     */
    public void update(Graphics g, JComponent c) {
	paint(g, c);
    }

    /**
     * Paints the interface.  This is routed to the
     * paintSafely method under the guarantee that
     * the model won't change from the view of this thread
     * while it's rendering (if the associated model is
     * derived from AbstractDocument).  This enables the 
     * model to potentially be updated asynchronously.
     *
     * @param g the graphics context
     * @param c the editor component
     */
    public final void paint(Graphics g, JComponent c) {
	if ((rootView.getViewCount() > 0) && (rootView.getView(0) != null)) {
	    Document doc = editor.getDocument();
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readLock();
	    }
	    try {
		paintSafely(g);
	    } finally {
		if (doc instanceof AbstractDocument) {
		    ((AbstractDocument)doc).readUnlock();
		}
	    }
	}
    }

    /**
     * Gets the preferred size for the editor component.  If the component
     * has been given a size prior to receiving this request, it will
     * set the size of the view hierarchy to reflect the size of the component
     * before requesting the preferred size of the view hierarchy.  This
     * allows formatted views to format to the current component size before
     * answering the request.  Other views don't care about currently formatted
     * size and give the same answer either way.
     *
     * @param c the editor component
     * @return the size
     */
    public Dimension getPreferredSize(JComponent c) {
	Document doc = editor.getDocument();
	Insets i = c.getInsets();
	Dimension d = c.getSize();

	if (doc instanceof AbstractDocument) {
	    ((AbstractDocument)doc).readLock();
	}
	try {
	    if ((d.width > (i.left + i.right)) && (d.height > (i.top + i.bottom))) {
		rootView.setSize(d.width - i.left - i.right, d.height - i.top - i.bottom);
	    }
            else if (d.width == 0 && d.height == 0) {
                // Probably haven't been layed out yet, force some sort of
                // initial sizing.
                rootView.setSize(Integer.MAX_VALUE, Integer.MAX_VALUE);
            }
	    d.width = (int) Math.min((long) rootView.getPreferredSpan(View.X_AXIS) +
				     (long) i.left + (long) i.right, Integer.MAX_VALUE);
	    d.height = (int) Math.min((long) rootView.getPreferredSpan(View.Y_AXIS) +
				      (long) i.top + (long) i.bottom, Integer.MAX_VALUE);
	} finally {
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readUnlock();
	    }
	}
	return d;
    }

    /**
     * Gets the minimum size for the editor component.
     *
     * @param c the editor component
     * @return the size
     */
    public Dimension getMinimumSize(JComponent c) {
	Document doc = editor.getDocument();
        Insets i = c.getInsets();
	Dimension d = new Dimension();
	if (doc instanceof AbstractDocument) {
	    ((AbstractDocument)doc).readLock();
	}
	try {
	    d.width = (int) rootView.getMinimumSpan(View.X_AXIS) + i.left + i.right;
	    d.height = (int)  rootView.getMinimumSpan(View.Y_AXIS) + i.top + i.bottom;
	} finally {
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readUnlock();
	    }
	}
        return d;
    }

    /**
     * Gets the maximum size for the editor component.
     *
     * @param c the editor component
     * @return the size
     */
    public Dimension getMaximumSize(JComponent c) {
	Document doc = editor.getDocument();
        Insets i = c.getInsets();
	Dimension d = new Dimension();
	if (doc instanceof AbstractDocument) {
	    ((AbstractDocument)doc).readLock();
	}
	try {
	    d.width = (int) Math.min((long) rootView.getMaximumSpan(View.X_AXIS) + 
				     (long) i.left + (long) i.right, Integer.MAX_VALUE);
	    d.height = (int) Math.min((long) rootView.getMaximumSpan(View.Y_AXIS) + 
				      (long) i.top + (long) i.bottom, Integer.MAX_VALUE);
	} finally {
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readUnlock();
	    }
	}
        return d;
    }

    // ---- TextUI methods -------------------------------------------


    /**
     * Gets the allocation to give the root View.  Due
     * to an unfortunate set of historical events this 
     * method is inappropriately named.  The Rectangle
     * returned has nothing to do with visibility.  
     * The component must have a non-zero positive size for 
     * this translation to be computed.
     *
     * @return the bounding box for the root view
     */
    protected Rectangle getVisibleEditorRect() {
	Rectangle alloc = editor.getBounds();
	if ((alloc.width > 0) && (alloc.height > 0)) {
	    alloc.x = alloc.y = 0;
	    Insets insets = editor.getInsets();
	    alloc.x += insets.left;
	    alloc.y += insets.top;
	    alloc.width -= insets.left + insets.right;
	    alloc.height -= insets.top + insets.bottom;
	    return alloc;
	}
	return null;
    }

    /**
     * Converts the given location in the model to a place in
     * the view coordinate system.
     * The component must have a non-zero positive size for 
     * this translation to be computed.
     *
     * @param tc the text component for which this UI is installed
     * @param pos the local location in the model to translate >= 0
     * @return the coordinates as a rectangle, null if the model is not painted
     * @exception BadLocationException  if the given position does not
     *   represent a valid location in the associated document
     * @see TextUI#modelToView
     */
    public Rectangle modelToView(JTextComponent tc, int pos) throws BadLocationException {
	return modelToView(tc, pos, Position.Bias.Forward);
    }

    /**
     * Converts the given location in the model to a place in
     * the view coordinate system.
     * The component must have a non-zero positive size for 
     * this translation to be computed.
     *
     * @param tc the text component for which this UI is installed
     * @param pos the local location in the model to translate >= 0
     * @return the coordinates as a rectangle, null if the model is not painted
     * @exception BadLocationException  if the given position does not
     *   represent a valid location in the associated document
     * @see TextUI#modelToView
     */
    public Rectangle modelToView(JTextComponent tc, int pos, Position.Bias bias) throws BadLocationException {
	Document doc = editor.getDocument();
	if (doc instanceof AbstractDocument) {
	    ((AbstractDocument)doc).readLock();
	}
	try {
	    Rectangle alloc = getVisibleEditorRect();
	    if (alloc != null) {
		rootView.setSize(alloc.width, alloc.height);
		Shape s = rootView.modelToView(pos, alloc, bias);
		if (s != null) {
		  return s.getBounds();
		}
	    }
	} finally {
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readUnlock();
	    }
	}
	return null;
    }

    /**
     * Converts the given place in the view coordinate system
     * to the nearest representative location in the model.
     * The component must have a non-zero positive size for 
     * this translation to be computed.
     *
     * @param tc the text component for which this UI is installed
     * @param pt the location in the view to translate.  This
     *  should be in the same coordinate system as the mouse events.
     * @return the offset from the start of the document >= 0,
     *   -1 if not painted
     * @see TextUI#viewToModel
     */
    public int viewToModel(JTextComponent tc, Point pt) {
	return viewToModel(tc, pt, discardBias);
    }

    /**
     * Converts the given place in the view coordinate system
     * to the nearest representative location in the model.
     * The component must have a non-zero positive size for 
     * this translation to be computed.
     *
     * @param tc the text component for which this UI is installed
     * @param pt the location in the view to translate.  This
     *  should be in the same coordinate system as the mouse events.
     * @return the offset from the start of the document >= 0,
     *   -1 if the component doesn't yet have a positive size.
     * @see TextUI#viewToModel
     */
    public int viewToModel(JTextComponent tc, Point pt,
			   Position.Bias[] biasReturn) {
	int offs = -1;
	Document doc = editor.getDocument();
	if (doc instanceof AbstractDocument) {
	    ((AbstractDocument)doc).readLock();
	}
	try {
	    Rectangle alloc = getVisibleEditorRect();
	    if (alloc != null) {
		rootView.setSize(alloc.width, alloc.height);
		offs = rootView.viewToModel(pt.x, pt.y, alloc, biasReturn);
	    }
	} finally {
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readUnlock();
	    }
	}
        return offs;
    }

    /**
     * {@inheritDoc}
     */
    public int getNextVisualPositionFrom(JTextComponent t, int pos,
		    Position.Bias b, int direction, Position.Bias[] biasRet)
	            throws BadLocationException{
	Document doc = editor.getDocument();
	if (doc instanceof AbstractDocument) {
	    ((AbstractDocument)doc).readLock();
	}
	try {
	    if (painted) {
		Rectangle alloc = getVisibleEditorRect();
                if (alloc != null) {
                    rootView.setSize(alloc.width, alloc.height);
                }
		return rootView.getNextVisualPositionFrom(pos, b, alloc, direction,
							  biasRet);
	    }
	} finally {
	    if (doc instanceof AbstractDocument) {
		((AbstractDocument)doc).readUnlock();
	    }
	}
	return -1;
    }

    /**
     * Causes the portion of the view responsible for the
     * given part of the model to be repainted.  Does nothing if
     * the view is not currently painted.
     *
     * @param tc the text component for which this UI is installed
     * @param p0 the beginning of the range >= 0
     * @param p1 the end of the range >= p0
     * @see TextUI#damageRange