JFreeChart放大缩小移动

package org.jfree.panning; import java.awt.Point; import java.awt.event.MouseEvent; import java.awt.event.MouseWheelEvent; import java.awt.event.MouseWheelListener; import java.awt.geom.Point2D; import java.awt.geom.Rectangle2D; import org.jfree.chart.ChartPanel; import org.jfree.chart.JFreeChart; import org.jfree.chart.axis.ValueAxis; import org.jfree.chart.plot.PlotOrientation; import org.jfree.chart.plot.PlotRenderingInfo; /** * A Swing GUI component for displaying a {@link JFreeChart} object. * <P> * The panel registers with the chart to receive notification of changes to any component of the * chart. The chart is redrawn automatically whenever this notification is received. */ public class PanningChartPanel extends ChartPanel implements MouseWheelListener { public static final int MOUSE_ZOOM = 1; public static final int MOUSE_PAN = 2; private int mouseMode = MOUSE_ZOOM; private int lastPanX = -1; private int lastPanY = -1; private Point2D panStartPoint = null; double zoomFactor = 0.9d; /** * Constructs a panel that displays the specified chart. * * @param chart the chart. */ public PanningChartPanel(JFreeChart chart) { super(chart); addMouseWheelListener(this); } /** * Constructs a panel containing a chart. * * @param chart the chart. * @param useBuffer a flag controlling whether or not an off-screen buffer is used. */ public PanningChartPanel(JFreeChart chart, boolean useBuffer) { super(chart, useBuffer); addMouseWheelListener(this); } /** * Constructs a JFreeChart panel. * * @param chart the chart. * @param properties a flag indicating whether or not the chart property editor should be * available via the popup menu. * @param save a flag indicating whether or not save options should be available via the popup * menu. * @param print a flag indicating whether or not the print option should be available via the * popup menu. * @param zoom a flag indicating whether or not zoom options should be added to the popup menu. * @param tooltips a flag indicating whether or not tooltips should be enabled for the chart. */ public PanningChartPanel(JFreeChart chart, boolean properties, boolean save, boolean print, boolean zoom, boolean tooltips) { super(chart, properties, save, print, zoom, tooltips); addMouseWheelListener(this); } /** * Constructs a JFreeChart panel. * * @param chart the chart. * @param width the preferred width of the panel. * @param height the preferred height of the panel. * @param minimumDrawWidth the minimum drawing width. * @param minimumDrawHeight the minimum drawing height. * @param maximumDrawWidth the maximum drawing width. * @param maximumDrawHeight the maximum drawing height. * @param useBuffer a flag that indicates whether to use the off-screen buffer to improve * performance (at the expense of memory). * @param properties a flag indicating whether or not the chart property editor should be * available via the popup menu. * @param save a flag indicating whether or not save options should be available via the popup * menu. * @param print a flag indicating whether or not the print option should be available via the * popup menu. * @param zoom a flag indicating whether or not zoom options should be added to the popup menu. * @param tooltips a flag indicating whether or not tooltips should be enabled for the chart. */ public PanningChartPanel(JFreeChart chart, int width, int height, int minimumDrawWidth, int minimumDrawHeight, int maximumDrawWidth, int maximumDrawHeight, boolean useBuffer, boolean properties, boolean save, boolean print, boolean zoom, boolean tooltips) { super(chart, width, height, minimumDrawWidth, minimumDrawHeight, maximumDrawWidth, maximumDrawHeight, useBuffer, properties, save, print, zoom, tooltips); addMouseWheelListener(this); } /** * Returns a point based on (x, y) but constrained to be within the bounds of the given * rectangle. This method could be moved to JCommon. * * @param x the x-coordinate. * @param y the y-coordinate. * @param area the rectangle (<code>null</code> not permitted). * @return A point within the rectangle. */ private Point getPointInRectangle(int x, int y, Rectangle2D area) { x = (int)Math.max(Math.ceil(area.getMinX()), Math.min(x, Math.floor(area.getMaxX()))); y = (int)Math.max(Math.ceil(area.getMinY()), Math.min(y, Math.floor(area.getMaxY()))); return new Point(x, y); } /** * Handles a 'mouse pressed' event. * <P> * This event is the popup trigger on Unix/Linux. For Windows, the popup trigger is the 'mouse * released' event. * * @param e The mouse event. */ @Override public void mousePressed(MouseEvent e) { if (e.isControlDown()) { this.mouseMode = MOUSE_PAN; Rectangle2D screenDataArea = getScreenDataArea(e.getX(), e.getY()); if (screenDataArea != null) { Point point = getPointInRectangle(e.getX(), e.getY(), screenDataArea); panStartPoint = point; lastPanX = point.x; lastPanY = point.y; } } else { this.mouseMode = MOUSE_ZOOM; } super.mousePressed(e); } /** * Handles a 'mouse dragged' event. * * @param e the mouse event. */ @Override public void mouseDragged(MouseEvent e) { if (this.mouseMode == MOUSE_PAN) { // panStartPoint might be null if the mouse was pressed between // two plots. if (panStartPoint == null) { // try to get a new start point if the user drags inside a plot // use the first point in the plot as start point Rectangle2D screenDataArea = getScreenDataArea(e.getX(), e.getY()); if (screenDataArea != null) { Point point = getPointInRectangle(e.getX(), e.getY(), screenDataArea); panStartPoint = point; } } else { move(panStartPoint, lastPanX, lastPanY, e.getX(), e.getY()); } lastPanX = e.getX(); lastPanY = e.getY(); return; } super.mouseDragged(e); } private void move(Point2D startPoint, int oldX, int oldY, int newX, int newY) { /* * this is selection of move direction. e.g. dragged to right -> what does this mean ? move * selection to right or left ? value of -1 is the typical graphic program behaviour */ double moveDirection = -1; double diffX = moveDirection * (newX - oldX); // * double diffY = -1 * moveDirection * (newY - oldY); // * // check for change if (diffX == 0 && diffY == 0) return; try { getChart().setNotify(false); if (getChart().getPlot() instanceof Pannable) { Pannable panningPlot = (Pannable)getChart().getPlot(); if (panningPlot.isDomainPannable()) { if (panningPlot.getOrientation() == PlotOrientation.VERTICAL) {