SWT/JFace：如何在TableViewerColumn中设置最大文本长度

Question

如何设置JFace中输入的最大字符数TableViewerColumn？有没有办法获得包含的控件并投射它？

所以，这里的（几乎）完整的类：

public class CustomerTab extends Composite implements ITableLabelProvider { 
    org.eclipse.swt.layout.GridLayout layout = null; 

    Table table = null; 

    GridData griddata = null; 

    TableViewer viewer = null; 

    private CustomerSearchFilter filter; 

    public CustomerTab(Composite arg1, int arg2) throws SQLException { 
     super(arg1, arg2); 

     layout = new org.eclipse.swt.layout.GridLayout(GridData.FILL_BOTH, 
       false); 
     layout.numColumns = 1; 

     this.setLayout(layout); 

     Button button = new Button(this, SWT.PUSH); 
     button.setText("New customer"); 
     button.addSelectionListener(new SelectionAdapter() { 
      public void widgetSelected(SelectionEvent e) { 

       WizardDialog wizardDialog = new WizardDialog(ApplicationRunner 
         .getApp().getShell(), new NewCustomerWizard()); 
       if (wizardDialog.open() == Window.OK) { 
        System.out.println("Ok pressed"); 
        try { 
         viewer.setInput(CustomerDAO.getInstance().getAll()); 
         viewer.refresh(); 
        } catch (SQLException e1) { 
         // TODO something 
        } 

       } else { 
        System.out.println("Cancel pressed"); 
       } 
      } 
     }); 

     final Text searchText = new Text(this, SWT.BORDER | SWT.SEARCH); 
     searchText.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL 
       | GridData.HORIZONTAL_ALIGN_FILL)); 

     addTable(); 

     // Support the search 
     searchText.addKeyListener(new KeyAdapter() { 
      public void keyReleased(KeyEvent ke) { 
       filter.setSearchText(searchText.getText()); 
       viewer.refresh(); 
      } 

     }); 
     filter = new CustomerSearchFilter(); 
     viewer.addFilter(filter); 
    } 

    public void addTable() throws SQLException { 

     viewer = new TableViewer(this, SWT.BORDER | SWT.MULTI 
       | SWT.FULL_SELECTION); 

     final Table table = viewer.getTable(); 
     table.setHeaderVisible(true); 
     table.setLinesVisible(true); 

     createColumns(this, viewer); 

     viewer.setContentProvider(new ArrayContentProvider()); 
     viewer.setInput(CustomerDAO.getInstance().getAll()); 

     GridData gridData = new GridData(); 
     gridData.verticalAlignment = GridData.FILL; 
     gridData.horizontalSpan = 2; 
     gridData.grabExcessHorizontalSpace = true; 
     gridData.grabExcessVerticalSpace = true; 
     gridData.horizontalAlignment = GridData.FILL; 
     viewer.getControl().setLayoutData(gridData); 
    } 

    private void createColumns(final Composite parent, final TableViewer viewer) { 
     String[] titles = { "ID", "Firma", "Anrede", "Vorname", "Nachname", 
       "Strasse", "Plz", "Ort", "Tel. privat", "Tel. gesch.", " " }; 
     int[] bounds = { 30, 130, 50, 100, 100, 100, 50, 100, 100, 100, 30 }; 



     // Col 1, ID 
     TableViewerColumn col = createTableViewerColumn(titles[0], bounds[0], 0); 
     col.setLabelProvider(new ColumnLabelProvider() { 
      @Override 
      public String getText(Object element) { 
       Customer p = (Customer) element; 
       return String.valueOf(p.getId()); 
      } 
     }); 
     col.setEditingSupport(new TestFirstNameEditingSupport(viewer)); 


     // other columns here... 

     // Col 4, Firstname 
     col = createTableViewerColumn(titles[3], bounds[3], 3); 
     col.setLabelProvider(new ColumnLabelProvider() { 
      @Override 
      public String getText(Object element) { 
       Customer p = (Customer) element; 
       return p.getFirstname(); 
      } 
     }); 
     col.setEditingSupport(new TestFirstNameEditingSupport(viewer)); 

     // and the rest of the columns here 

    } 

    private TableViewerColumn createTableViewerColumn(String title, int bound, 
      final int colNumber) { 
     final TableViewerColumn viewerColumn = new TableViewerColumn(viewer, 
       SWT.NONE); 
     final TableColumn column = viewerColumn.getColumn(); 
     column.setText(title); 
     column.setWidth(bound); 
     column.setResizable(true); 
     column.setMoveable(true); 
     return viewerColumn; 
    } 

    // LabelProvider 
    @Override 
    public void addListener(ILabelProviderListener arg0) { 
    } 

    @Override 
    public boolean isLabelProperty(Object arg0, String arg1) { 
     return false; 
    } 

    @Override 
    public void removeListener(ILabelProviderListener arg0) { 
    } 

    @Override 
    public Image getColumnImage(Object arg0, int arg1) { 
     return null; 
    } 

    @Override 
    public String getColumnText(Object arg0, int arg1) { 

     String result = ""; 
     switch (arg1) { 
     case 0: 
      result = "ID"; 
      break; 
     ... 

     case 4: 
      result = "Firstname"; 
      break; 
     ... 

     default: 
      // should not get here 
      result = ""; 
     } 
     return result; 
    } 

    static class TestFirstNameEditingSupport extends EditingSupport { 

     private final TableViewer viewer; 
     private TextCellEditor editor = null; 

     public TestFirstNameEditingSupport(TableViewer viewer) { 
      super(viewer); 
      this.viewer = viewer; 
      editor = new TextCellEditor(viewer.getTable()); 

      Text text = (Text) editor.getControl(); 

      // set maximal length HERE 
      text.setTextLimit(3); 
     } 

     public CellEditor getMyCellEditor(Object element) { 
      return editor; 
     } 

     @Override 
     protected CellEditor getCellEditor(Object element) { 
      return new TextCellEditor(viewer.getTable()); 
     } 

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

     @Override 
     protected Object getValue(Object element) { 
      return ((de.devision.data.bean.Customer) element).getVorname(); 
     } 

     @Override 
     protected void setValue(Object element, Object value) { 

      if (String.valueOf(value).length() <= 2 || String.valueOf(value).equals("")) { 
       MessageDialog.openInformation(ApplicationRunner.getApp().getShell(), "to short!", "at least 3 characters!"); 
       return; 
      } 

      ((Customer) element).setVorname(String.valueOf(value)); 

      try { 
       CustomerDAO.getInstance().update(((Customer) element)); 
      } catch (SQLException e) { 
       // TODO maybe later 
      } 
      viewer.refresh(); 
     } 
    } 
} 

Answer 1

好吧，终于得到了它的工作：

private static void createViewer(Composite parent) { 
    viewer = new TableViewer(parent, SWT.MULTI | SWT.H_SCROLL 
      | SWT.V_SCROLL | SWT.FULL_SELECTION | SWT.BORDER); 
    createColumns(parent, viewer); 
    final Table table = viewer.getTable(); 
    table.setHeaderVisible(true); 
    table.setLinesVisible(true); 

    viewer.setContentProvider(new ArrayContentProvider()); 
    // Get the content for the viewer, setInput will call getElements in the 
    // contentProvider 
    viewer.setInput(ModelProvider.INSTANCE.getPersons()); 
    // Set the sorter for the table 

    // Layout the viewer 
    GridData gridData = new GridData(); 
    gridData.verticalAlignment = GridData.FILL; 
    gridData.horizontalSpan = 2; 
    gridData.grabExcessHorizontalSpace = true; 
    gridData.grabExcessVerticalSpace = true; 
    gridData.horizontalAlignment = GridData.FILL; 
    viewer.getControl().setLayoutData(gridData); 

    comparator = new PersonViewerComparator(); 
    viewer.setComparator(comparator); 
} 

// This will create the columns for the table 
private static void createColumns(final Composite parent, 
     final TableViewer viewer) { 
    String[] titles = { "First name", "Last name", "Gender", "Married" }; 
    int[] bounds = { 100, 100, 100, 100 }; 

    // First column is for the first name 
    TableViewerColumn col = createTableViewerColumn(titles[0], bounds[0], 0); 
    col.setLabelProvider(new ColumnLabelProvider() { 
     @Override 
     public String getText(Object element) { 
      Person p = (Person) element; 
      return p.getFirstName(); 
     } 
    }); 

    col.setEditingSupport(new CheckLengthEditingSupport(viewer)); 

    // Second column is for the last name 
    col = createTableViewerColumn(titles[1], bounds[1], 1); 
    col.setLabelProvider(new ColumnLabelProvider() { 
     @Override 
     public String getText(Object element) { 
      Person p = (Person) element; 
      return p.getLastName(); 
     } 
    }); 

    // Now the gender 
    col = createTableViewerColumn(titles[2], bounds[2], 2); 
    col.setLabelProvider(new ColumnLabelProvider() { 
     @Override 
     public String getText(Object element) { 
      Person p = (Person) element; 
      return p.getGender(); 
     } 
    }); 

    // // Now the status married 
    col = createTableViewerColumn(titles[3], bounds[3], 3); 
    col.setLabelProvider(new ColumnLabelProvider() { 
     @Override 
     public String getText(Object element) { 
      return ""; 
     } 

     @Override 
     public Image getImage(Object element) { 
      if (((Person) element).isMarried()) { 
       return CHECKED; 
      } else { 
       return UNCHECKED; 
      } 
     } 
    }); 
} 

static class CheckLengthEditingSupport extends EditingSupport { 

    private final TableViewer viewer; 
    private TextCellEditor editor = null; 

    public FirstNameEditingSupport(TableViewer viewer) { 
     super(viewer); 
     this.viewer = viewer; 
     editor = new TextCellEditor(viewer.getTable()); 

     Text text = (Text) editor.getControl(); 

     // set maximal length HERE 
     text.setTextLimit(3); 
    } 

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

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

    @Override 
    protected Object getValue(Object element) { 
     return ((YourObject) element).getName(); 
    } 

    @Override 
    protected void setValue(Object element, Object value) { 
     ((YourObject) element).setName(String.valueOf(value)); 
     viewer.update(element, null); 
    } 
} 

您必须设置TextCellEditor的EditingSupport类中，并在返回它protected CellEditor getCellEditor(Object element)方法。

顺便说一句：如果你想要另一个限制比“少于x个字符”，你可以简单地将VerifyListener添加到TextCellEditor中的text。