如何更改JFreeChart的大小

Question

我添加了JFreeChart一个JPanel(使用a BorderLayout),它是巨大的.有什么我可以做的让它变小吗？

public void generateChart()
{
    DefaultCategoryDataset dataset = new DefaultCategoryDataset();

    //set the values of the chart
    for(int i=0; i<8; i++)
    {
        dataset.setValue(income_array[i], "Income",
            Double.toString(percent_array[i]));
    }

    JFreeChart chart = ChartFactory.createBarChart(
        "Required Annual Income for a Variety of Interest Rates",
        "Percent", "Income", dataset, PlotOrientation.VERTICAL,
        false,true, false);
    ChartPanel cp = new ChartPanel(chart);

    chart.setBackgroundPaint(Color.white);
    chart.getTitle().setPaint(Color.black); 
    CategoryPlot p = chart.getCategoryPlot(); 
    p.setRangeGridlinePaint(Color.blue); 

    //cp.setMaximumDrawHeight(5);
    //cp.setMaximumDrawWidth(5);
    //cp.setZoomOutFactor(.1);
    JPanel graph = new JPanel();
    graph.add(cp);
    middle.add(graph, BorderLayout.CENTER);
}   

Answer 1

创建时ChartPanel,您有几个影响结果的选项:

1. 接受DEFAULT_WIDTH和DEFAULT_HEIGHT:680 x 420.

2. 指定首选width和height在构造.

3. setPreferredSize()如果合适,则显式调用.

4. 覆盖getPreferredSize()以动态计算大小.

   @Override
   public Dimension getPreferredSize() {
       // given some values of w & h
       return new Dimension(w, h);
   }
   

5. 选择要添加的容器的布局ChartPanel.请注意,默认布局JPanel是FlowLayout,JFrame而是BorderLayout.作为一个具体示例,ThermometerDemo在构造函数中使用首选值,GridLayout对容器使用允许动态调整大小的值.