treeview2.java

一个Web爬虫（机器人

		{
		    requestFocus();

                    //int x = event.getX(); JDK1.1
                    //int y = event.getY();

			int index = (y / cellSize) + sbVPosition;

			//If clicked below the last node
			if (index > viewCount-1)
				return true;

			TreeNode2 oldNode = selectedNode;
			TreeNode2 newNode = (TreeNode2)v.elementAt(index);
			int newDepth = newNode.getDepth();

			changeSelection(newNode);
			// check for toggle box click
			// todo: make it a bit bigger
			Rectangle toggleBox = new Rectangle(cellSize*newDepth + cellSize/4 - sbHPosition,
						                        (index-sbVPosition)*cellSize + clickSize/2,
						                        clickSize, clickSize);

			if (toggleBox.inside(x,y))
			{
				newNode.toggle();
				//sendActionEvent();
				triggerRedraw();
			}
			else
			{
				// check for double click
				if ((newNode==oldNode) && event.clickCount == 2)
				{
                                    //newNode.toggle();
                                    //triggerRedraw();
					sendActionEvent();
				}
				else
				{
					//single click action could be added here
                                    //timeMouseDown = event.getWhen();
				}

			}
                        return true;
		}
        //}

    //class Key extends KeyAdapter JDK1.1
    //{
	    /**
	     * Processes KEY_PRESS and KEY_ACTION events.
	     * This is a standard Java AWT method which gets called by the AWT
	     * method handleEvent() in response to receiving a KEY_PRESS or
	     * KEY_ACTION event. These events occur when this component has the focus
	     * and the user presses a "normal" or an "action" (F1, page up, etc) key.
	     *
	     * @param event the Event
	     * @param key the key that was pressed
	     * @return true if the event was handled
	     * @see java.awt.Component#keyUp
	     * @see #handleEvent
	     */
		public boolean keyDown(Event event, int key)
		{
		    int index = v.indexOf(selectedNode);

		    switch (key)
		    {
		        //case KeyEvent.VK_ENTER:    //enter key
		        case 13:
		            sendActionEvent();
		            requestFocus();
		            break;
		        case Event.LEFT:    //left arrow
		            if(event.controlDown())
                    {
	                    if(sbHPosition > 0)
                        {
                            horizontalScrollBar.setValue(Math.max(sbHPosition-=sbHLineIncrement,0));
                            repaint();
                        }
                        break;
	                }
	                else
		            if (selectedNode.isExpanded())
		            {
		                selectedNode.toggle();
		                triggerRedraw();
		                break;
		            }

		            // else drop through to "UP" with no "break;"
		        case Event.UP:
		            if (index > 0)
		            {
		                index--;
		                changeSelection((TreeNode2)v.elementAt(index));
		                requestFocus();
		            }
		            break;
		        case Event.RIGHT:
		            if(event.controlDown())
    	            {
	                    int max = horizontalScrollBar.getMaximum()-(isSun1_1?size().width-sbVWidth:0);
	                    if(sbHShow && sbHPosition < max)
                        {
                            horizontalScrollBar.setValue(Math.min(sbHPosition+=sbHLineIncrement, max));
                            repaint();
                        }
                        break;
	                }
	                else
		            if (selectedNode.isExpandable() && (!selectedNode.isExpanded()))
		            {
		                selectedNode.toggle();
		                //sendActionEvent();
		                triggerRedraw();
                                break;
		            }

		            if (!selectedNode.isExpandable())
		            {
                                break;
		            }
		            // else drop thru' to DOWN
		        case Event.DOWN:
		            if (index < viewCount-1)
		            {
		                index++;
		                changeSelection((TreeNode2)v.elementAt(index));
		                requestFocus();
                                break;
		            }
		            break;

                    default:
                        return false;
		    }
                    return true;
		}
	//}

//class Focus extends FocusAdapter JDK1.1
//{
        public boolean gotFocus (Event e, Object what)
        {
            hasFocus = true;
            if (selectedNode != null && v != null)
                drawNodeText(selectedNode,    (v.indexOf(selectedNode) - sbVPosition)*cellSize, true);
            return true;
        }

        public boolean focusLost(Event e, Object what)
        {
            hasFocus = false;
            if (selectedNode != null && v != null)
                drawNodeText(selectedNode,    (v.indexOf(selectedNode) - sbVPosition)*cellSize, true);
            return true;
        }
//}

	protected void sendActionEvent()
	{
            /*
		if (actionListener != null)
			actionListener.actionPerformed(new ActionEvent(this, ActionEvent.ACTION_PERFORMED, new String(selectedNode.getText())));
            */
            deliverEvent (new Event (this, Event.ACTION_EVENT, selectedNode.getText()));
	}

	/**
	 * Gets the currently selected node.
	 * @return the currently selected node, or null if none selected
	 */
	public TreeNode2 getSelectedNode()
	{
	    return selectedNode;
	}

	/**
	 * Gets the text of the currently selected node.
	 * @return the text of the currently selected node or null if no node
	 * is selected
	 */
	public String getSelectedText()
	{
	    if (selectedNode == null)
	        return null;

	    return selectedNode.getText();
	}

	protected void changeSelection(TreeNode2 node)
	{
	    if (node == selectedNode)
	        return;

	    TreeNode2 oldNode = selectedNode;
	    selectedNode = node;
	    drawNodeText(oldNode, (v.indexOf(oldNode) - sbVPosition)*cellSize, true);
	    drawNodeText(node,    (v.indexOf(node)    - sbVPosition)*cellSize, true);
	    // send select event

	    int index = v.indexOf(selectedNode);

            /* FIX: replace with SEL_CHANGED event?
		if (itemListener != null)
		{
			itemListener.itemStateChanged(new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, oldNode, ItemEvent.DESELECTED));
			itemListener.itemStateChanged(new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, selectedNode, ItemEvent.SELECTED));
		}
            */

	    if (index < sbVPosition)
	    { //scroll up
	        sbVPosition--;
	        verticalScrollBar.setValue(sbVPosition);
	        triggerRedraw();
	        return;
	    }

	    if (index >= sbVPosition + (viewHeight-cellSize/2)/cellSize)
	    {
	        sbVPosition++;
	        verticalScrollBar.setValue(sbVPosition);
	        triggerRedraw();
	        return;
	    }

	    repaint();
	}

	// -----------------------------------------
	// --------- graphics related methods ------
	// -----------------------------------------
    /**
     * Handles redrawing of this component on the screen.
     * This is a standard Java AWT method which gets called by the Java
     * AWT (repaint()) to handle repainting this component on the screen.
     * The graphics context clipping region is set to the bounding rectangle
     * of this component and its [0,0] coordinate is this component's
     * top-left corner.
     * Typically this method paints the background color to clear the
     * component's drawing space, sets graphics context to be the foreground
     * color, and then calls paint() to draw the component.
     *
     * It is overridden here to reduce flicker by eliminating the uneeded
     * clearing of the background.
     *
     * @param g the graphics context
     * @see java.awt.Component#repaint
     * @see #paint
     */
	public synchronized void update (Graphics g)
	{
	    //(eliminates background draw to reduce flicker)
	    paint(g);
	}

	/**
	 * Paints this component using the given graphics context.
     * This is a standard Java AWT method which typically gets called
     * by the AWT to handle painting this component. It paints this component
     * using the given graphics context. The graphics context clipping region
     * is set to the bounding rectangle of this component and its [0,0]
     * coordinate is this component's top-left corner.
     *
     * @param g the graphics context used for painting
     * @see java.awt.Component#repaint
     * @see #update
	 */
	public void paint (Graphics g)
	{
		Dimension d = size();
        if ((d.width != viewWidth) || (d.height != viewHeight))
            triggerRedraw ();

		if (redrawTriggered)
		{
			// redraw needed, or size has changed
			redraw(g);
		}
                /*
		//???RKM??? Is this really needed
		else if (java.beans.Beans.isDesignTime())
		{
			resetVector();
			newWidth = compWidth(g);
			drawTree();
		}
                */

		g.translate(-sbHPosition, 0);
                //g.clearRect(sbHPosition,0,d.width-sbVWidth,d.height-sbHHeight);
        if (sbVShow && sbHShow)
        {
            g.setColor(Color.lightGray);
            g.fillRect(sbHPosition+d.width-sbVWidth, d.height-sbHHeight, sbVWidth, sbHHeight);
        }
        g.clipRect(sbHPosition,0,d.width-sbVWidth,d.height-sbHHeight);
		g.drawImage(im1, 0, 0, this);
		g.setColor(Color.black);
        g.drawRect(sbHPosition,0, d.width-sbVWidth-1, d.height-sbHHeight-1);

	}

    /**
     * Lays out the vertical scrollbar as needed, then draws the TreeView2 into
     an offscreen image. This is used for cleaner refresh.
     */
    public void redraw()
    {
        //For backward compatibality. Do not allow to call only redraw() without recalculation.
        triggerRedraw();
    }

	public void redraw(Graphics g)
	{
	    boolean recalculate = treeChanged;
	    int inRectCount = 0;
	    
		redrawTriggered = false;
        treeChanged = false;
	    
        Dimension d = size();

        if (recalculate) {
            
    	    resetVector();

            newWidth = compWidth(g);

            inRectCount = ((d.height-sbHHeight)/cellSize);
    	    if (viewCount > inRectCount)
    	    {
      	        // need the vertical scrollbar
    	        sbVShow = true;
    	        sbVWidth = verticalScrollBar.preferredSize().width;
    	    }
    	    else
    	    {
      	        sbVShow = false;
    	        sbVWidth = 0;
    	        sbVPosition = 0;
    	    }

    	    if (newWidth > (d.width-sbVWidth))
    	    {
    	        // need the horizontal scrollbar
    	        sbHShow = true;
    			sbHHeight = horizontalScrollBar.preferredSize().height;
    	    }
    	    else
    	    {
    	        sbHShow = false;
                sbHHeight = 0;
                sbHPosition = 0;
    	    }

        }
        
        drawTree();

        if (recalculate) {
	        verticalScrollBar.setValues(sbVPosition, inRectCount, 0, viewCount-(isSun1_1?0:inRectCount));
			verticalScrollBar.setPageIncrement(inRectCount-1);

            horizontalScrollBar.setValues(sbHPosition, d.width-sbVWidth, 0, sbHSize-(isSun1_1?0:(d.width-sbVWidth)));
            horizontalScrollBar.setPageIncrement(d.width-sbVWidth);
            horizontalScrollBar.setLineIncrement(sbHLineIncrement);

    	    if (sbVShow)
    	    {
    	        verticalScrollBar.reshape(d.width-sbVWidth,0,sbVWidth,d.height-sbHHeight);
    	        verticalScrollBar.show();
    	    }
    	    else
    	    {
    	        verticalScrollBar.hide();
    	    }
        	
            if (sbHShow)
    	    {
    	        horizontalScrollBar.reshape(0,d.height-sbHHeight,d.width-sbVWidth,sbHHeight);
                horizontalScrollBar.show();
    	    }
    	    else
    	    {
    	        horizontalScrollBar.hide();
    	    }
        }
	}

    private int compWidth(Graphics gg)
    {
        int size = 0;
        int textOffset;
        TreeNode2 node;

   	    Font f = getFont();  //unix version might not provide a default font
		//Make certain there is a font
	    if (f == null)
	    {
	        f = new Font("TimesRoman", Font.PLAIN, 13);
	        gg.setFont(f);
	        setFont(f);
	    }

	    fm = gg.getFontMetrics();

        for (int i=0; i<v.size(); i++)
        {
            node = (TreeNode2)v.elementAt(i);
       	    textOffset = ((node.depth + 1) * (cellSize)) + cellSize + textInset - (node.getImage()==null ? 12:0);
       	    if (size < (textOffset+fm.stringWidth(node.text)+6))
    	        size = textOffset+fm.stringWidth(node.text)+6;
        }

        return size;
    }
    /**
     * Draws the TreeView2 into an offscreen image. This is used for cleaner refresh.
     */
	public void drawTree()
	{
		Dimension d = size();

		if ((d.width != viewWidth) || (d.height != viewHeight) || (g1==null) || (sbHSize!=newWidth))
		{
	        // size has changed, must resize image
			im1 = createImage(Math.max(sbHSize=newWidth, d.width), d.height);
			if (g1 != null) {
				g1.dispose();
			}
	        g1 = im1.getGraphics();
	        viewWidth=d.width;
	        viewHeight=d.height;
		}

	    Font f = getFont();  //unix version might not provide a default font

		//Make certain there is a font
	    if (f == null)
	    {
	        f = new Font("TimesRoman", Font.PLAIN, 13);
	        g1.setFont(f);
	        setFont(f);
	    }

	    //Make certain the graphics object has a font (Mac doesn't seem to)
		if (f != null)
		{