将监听器添加到 Java 类中的方法

Question

我很难实现一个方法的监听器。

我有一个创建表的方法fillTableRoWData()。该方法在两个 if 条件内同时调用。

我已将所有值存储在 hahMap 中。

问题是当我更新组合框值时：仅更新第二个条件中的值。

我想添加一个监听器，告诉方法哪个 if 条件被更新，并在相关的 hashMap 位置添加数据。

此外，当我将数据输入任何 TableColoumn 时，数据应该在 HashMap 中更新

package view;

import java.util.HashMap;

import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.TableEditor;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.TableItem;
import org.eclipse.swt.widgets.Text;

public class TableShellExample {

    Display d;

    Shell s;

    Table table;
    private Text text_1, text_2, text_3, text_4;
    private HashMap<Integer, String> list2 = new HashMap<>();
    private HashMap<Integer, HashMap<Integer, String>> list3 = new HashMap<>();
    private static Integer a = 0;
    private static Integer q = 0;

    TableShellExample() {
        d = new Display();
        s = new Shell(d);

        s.setSize(250, 200);

        s.setText("A Table Shell Example");


        Table table = new Table(s, SWT.BORDER);

        String[] titles = { "Theart Name", "Category", "Satus", "Priority",
                "Description", "Justification" };
        for (int i = 0; i < titles.length; i++) {
            TableColumn column = new TableColumn(table, SWT.NONE);
            column.setWidth(150);
            column.setText(titles[i]);
        }

        table.setHeaderVisible(true);

        fillRows("1","2","3");



        s.open();
        while (!s.isDisposed()) {
            if (!d.readAndDispatch())
                d.sleep();
        }
        d.dispose();
    }


    private void fillRows(String shortdesc, String categ, String descp) {
        TableItem item = new TableItem(table, SWT.NONE);

        // for Threat_Name
        TableEditor editor = new TableEditor(table);

        text_1 = new Text(table, SWT.READ_ONLY);
        editor.grabHorizontal = true;
        editor.setEditor(text_1, item, 0);
        text_1.setText(shortdesc);
        // list2.put(a++, text_1.getText());
        System.out.println(a + " : " + list2);

        // For Category_Name
        //editor = new TableEditor(table);
        text_2 = new Text(table, SWT.READ_ONLY);
        editor.grabHorizontal = true;
        editor.setEditor(text_2, item, 1);
        text_2.setText(categ);
        // list2.put(a++, text_2.getText());
        System.out.println(a + " : " + list2);

        // For Status_Name
        editor = new TableEditor(table);
        final Combo Status_Combo = new Combo(table, SWT.READ_ONLY);
        Status_Combo.add("Mitigated");
        Status_Combo.add("Not Applicable");
        Status_Combo.add("Not Started");
        Status_Combo.add("Needs Investigation");
        editor.grabHorizontal = true;
        editor.setEditor(Status_Combo, item, 2);

        Status_Combo.addSelectionListener(new SelectionListener() {
            public void widgetSelected(SelectionEvent e) {
                System.out.println(Status_Combo.getText());
            }

            public void widgetDefaultSelected(SelectionEvent e) {
                System.out.println(Status_Combo.getText());
            }
        });

        // For Priority_Name
        editor = new TableEditor(table);
        final Combo priority_Combo = new Combo(table, SWT.READ_ONLY);
        priority_Combo.add("High");
        priority_Combo.add("Medium");
        priority_Combo.add("Low");
        editor.grabHorizontal = true;
        editor.setEditor(priority_Combo, item, 3);

        priority_Combo.addSelectionListener(new SelectionListener() {
            public void widgetSelected(SelectionEvent e) {
                System.out.println(priority_Combo.getText());
            }

            public void widgetDefaultSelected(SelectionEvent e) {
                System.out.println(priority_Combo.getText());
            }
        });

        // For Descrption_Name
        editor = new TableEditor(table);
        text_3 = new Text(table, SWT.READ_ONLY);
        editor.grabHorizontal = true;
        editor.setEditor(text_3, item, 4);
        text_3.setText(descp);
        // list2.put(a++, text_3.getText());
        System.out.println(a + " : " + list2);

        System.out.println(list3);

        // For justification
        editor = new TableEditor(table);
        text_4 = new Text(table, SWT.MULTI | SWT.BORDER | SWT.WRAP
                | SWT.V_SCROLL);
        editor.grabHorizontal = true;
        editor.setEditor(text_4, item, 5);

        list3.put(q++, new HashMap() {
            {
                put(a, text_1.getText());
                put((a + 1), text_2.getText());
                put((a + 2), text_3.getText());
            }
        });

    }

    public static void main(String[] argv) {
        new TableShellExample();
    }

}

Answer 1

您真的应该考虑使用TableViewer 和EditingSupport。通过这样做，您不需要跟踪选定的值，它们将存储在您的 bean 类中。这是一个非常简单的示例，它显示了一个包含一个组合框列的表格，您可以在其中从两个值中进行选择：

import org.eclipse.jface.layout.*;
import org.eclipse.jface.viewers.*;
import org.eclipse.swt.*;
import org.eclipse.swt.layout.*;
import org.eclipse.swt.widgets.*;

import java.util.*;
import java.util.List;


/**
 * @author Sebastian Raubach
 */
public class StackOverflow
{
    public static void main(String[] args)
    {
        final Display display = new Display();
        final Shell shell = new Shell(display);
        shell.setText("StackOverflow");
        shell.setLayout(new GridLayout());

        createMasterPart(shell);

        shell.pack();
        shell.setSize(400, 300);
        shell.open();

        shell.layout(true, true);

        while (!shell.isDisposed())
        {
            if (!display.readAndDispatch())
                display.sleep();
        }
        display.dispose();
    }

    private static void createMasterPart(Composite parentComposite)
    {
        Composite composite = new Composite(parentComposite, SWT.NONE);
        composite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
        composite.setLayout(new GridLayout(1, false));

        Composite tableComposite = new Composite(composite, SWT.NONE);
        TableColumnLayout tableColumnLayout = new TableColumnLayout();
        tableComposite.setLayout(tableColumnLayout);
        tableComposite.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));

        TableViewer tableViewer = new TableViewer(tableComposite, SWT.BORDER | SWT.FULL_SELECTION);
        tableViewer.setContentProvider(ArrayContentProvider.getInstance());

        Table table = tableViewer.getTable();
        table.setHeaderVisible(true);
        table.setLinesVisible(true);

        TableViewerColumn tableViewerColumn = new TableViewerColumn(tableViewer, SWT.NONE);
        TableColumn tableColumn = tableViewerColumn.getColumn();
        tableColumn.setText("Sample");
        tableViewerColumn.setLabelProvider(new ColumnLabelProvider()
        {
            @Override
            public String getText(Object element)
            {
                Dummy p = (Dummy) element;
                return p.getValue();
            }
        });

        tableViewer.addSelectionChangedListener(new ISelectionChangedListener()
        {
            @Override
            public void selectionChanged(SelectionChangedEvent selectionChangedEvent)
            {
                StructuredSelection selection = (StructuredSelection) selectionChangedEvent.getSelection();

                System.out.println(((Dummy) selection.getFirstElement()).getValue());
            }
        });

        List<Dummy> elements = new ArrayList<>();

        for (int i = 0; i < 20; i++)
        {
            elements.add(new Dummy("First option"));
        }

        tableViewer.setInput(elements);

        tableColumnLayout.setColumnData(tableColumn, new ColumnWeightData(1, true));

            /* Set the editing support here */
        tableViewerColumn.setEditingSupport(new FirstValueEditingSupport(tableViewer));
    }

    private static class Dummy
    {
        public String value;

        public Dummy(String value)
        {
            this.value = value;
        }

        public String getValue()
        {
            return value;
        }

        public void setValue(String value)
        {
            this.value = value;
        }
    }

    public static class FirstValueEditingSupport extends EditingSupport
    {

        private final TableViewer viewer;
        private final CellEditor  editor;

        private final String[] possibleValues = {"First option", "Second option"};

        public FirstValueEditingSupport(TableViewer viewer)
        {
            super(viewer);
            this.viewer = viewer;
            this.editor = new ComboBoxCellEditor(viewer.getTable(), possibleValues);
        }

        @Override
        protected CellEditor getCellEditor(Object element)
        {
            return editor;
        }

        @Override
        protected boolean canEdit(Object element)
        {
            return true;
        }

        @Override
        protected Object getValue(Object element)
        {
            Dummy dummy = (Dummy) element;

            int index = 0;

            for (int i = 0; i < possibleValues.length; i++)
            {
                if (Objects.equals(possibleValues[i], dummy.getValue()))
                {
                    index = i;
                    break;
                }
            }

            return index;
        }

        @Override
        protected void setValue(Object element, Object value)
        {
            Dummy dummy = (Dummy) element;

            int index = (Integer) value;

            dummy.setValue(possibleValues[index]);

            viewer.update(element, null);
        }
    }
}

当你选择一个项目时，它会打印当前的选择。