JFreeChart饼图未在RCP viewpart中扩展

Question

使用GridLayout时，JFreeChart饼图不会展开以填充复合面板。 我正在尝试在带有Eclipse Indigo的viewpart中使用它，但它似乎仅在shell中使用FillLayout时才起作用。

public class SWTPieChart {  
    public static void main(String[] args) {        
        JFreeChart chart = createChart(createDataset());
        Display display = new Display();
        Shell shell = new Shell(display);
        shell.setSize(600, 400);
        shell.setLayout(new FillLayout());
        shell.setText("JFreeChart with GridLayout");

        Composite panel = new Composite(shell, SWT.BORDER);
        panel.setLayout(new GridLayout(1, true));
        panel.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

        final ChartComposite frame = new ChartComposite(panel, SWT.NONE, chart, true);
        frame.pack();
        shell.open();
        while (!shell.isDisposed())
        {
            if (!display.readAndDispatch())
                display.sleep();
        }
    }

    private static PieDataset createDataset() {
        DefaultPieDataset dataset = new DefaultPieDataset();
        dataset.setValue("One", new Double(43.2));
        dataset.setValue("Two", new Double(10.0));
        dataset.setValue("Three", new Double(27.5));
        dataset.setValue("Four", new Double(17.5));
        dataset.setValue("Five", new Double(11.0));
        dataset.setValue("Six", new Double(19.4));
        return dataset;        
    }

    private static JFreeChart createChart(PieDataset dataset) {
        JFreeChart chart = ChartFactory.createPieChart3D("3D Pie Chart", dataset, true, true, false);

        PiePlot3D plot = (PiePlot3D) chart.getPlot();
        plot.setSectionOutlinesVisible(true);
        plot.setLabelFont(new Font("SansSerif", Font.PLAIN, 12));
        plot.setNoDataMessage("No data available");
        plot.setCircular(true);
        return chart;
    }
}

Answer 1

您错误地将布局数据设置为组合（ panel ）而不是图表（ frame ）。

由于复合材料位于带有FillLayout的外壳内部，因此无需设置任何布局数据。

相反，该图表位于带有GridLayout的组合内部，因此它必须为其指定布局数据：

 Composite panel = new Composite(shell, SWT.BORDER);
 panel.setLayout(new GridLayout(1, true));

 final ChartComposite frame = new ChartComposite(panel, SWT.NONE, chart, true);
 frame.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));