如何获得JFace的TableViewer的有序元素? [英] How can I get the ordered elements of a JFace's TableViewer?

问题描述

我已经根据 Vogella的说明实现了JFace的TableViewer排序转载如下).碰巧排序仅在图形界面中进行(未反映在原始数据结构中)，我需要按在GUI中显示的顺序获取元素.

I have implemented the JFace's TableViewer sorting according to Vogella's instructions (reproduced below). It happens that the sorting is made in the graphical interface only (it is not reflected in the original data structure) and I need o get the elements in the order they are displayed in the GUI.

或者，反映原始数据结构中的排序的实现也将适用.

Alternatively, an implementation which reflects the sorting in the original data structure would fit too.

package de.vogella.jface.tableviewer.sorter;

import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;
import org.eclipse.swt.SWT;

import de.vogella.jface.tableviewer.model.Person;

public class MyViewerComparator extends ViewerComparator {
  private int propertyIndex;
  private static final int DESCENDING = 1;
  private int direction = DESCENDING;

  public MyViewerComparator() {
    this.propertyIndex = 0;
    direction = DESCENDING;
  }

  public int getDirection() {
    return direction == 1 ? SWT.DOWN : SWT.UP;
  }

  public void setColumn(int column) {
    if (column == this.propertyIndex) {
      // Same column as last sort; toggle the direction
      direction = 1 - direction;
    } else {
      // New column; do an ascending sort
      this.propertyIndex = column;
      direction = DESCENDING;
    }
  }

  @Override
  public int compare(Viewer viewer, Object e1, Object e2) {
    Person p1 = (Person) e1;
    Person p2 = (Person) e2;
    int rc = 0;
    switch (propertyIndex) {
    case 0:
      rc = p1.getFirstName().compareTo(p2.getFirstName());
      break;
    case 1:
      rc = p1.getLastName().compareTo(p2.getLastName());
      break;
    case 2:
      rc = p1.getGender().compareTo(p2.getGender());
      break;
    case 3:
      if (p1.isMarried() == p2.isMarried()) {
        rc = 0;
      } else
        rc = (p1.isMarried() ? 1 : -1);
      break;
    default:
      rc = 0;
    }
    // If descending order, flip the direction
    if (direction == DESCENDING) {
      rc = -rc;
    }
    return rc;
  }

}

---

package de.vogella.jface.tableviewer;

import org.eclipse.jface.viewers.ArrayContentProvider;
import org.eclipse.jface.viewers.ColumnLabelProvider;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.viewers.TableViewerColumn;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.part.ViewPart;

import de.vogella.jface.tableviewer.model.ModelProvider;
import de.vogella.jface.tableviewer.model.Person;
import de.vogella.jface.tableviewer.sorter.MyViewerComparator;

public class View extends ViewPart {
  public static final String ID = "de.vogella.jface.tableviewer.view";
  private MyViewerComparator comparator;

  private TableViewer viewer;
  // We use icons
  private static final Image CHECKED = Activator.getImageDescriptor("icons/checked.gif").createImage();
  private static final Image UNCHECKED = Activator.getImageDescriptor("icons/unchecked.gif").createImage();

  public void createPartControl(Composite parent) {
    GridLayout layout = new GridLayout(2, false);
    parent.setLayout(layout);
    Label searchLabel = new Label(parent, SWT.NONE);
    searchLabel.setText("Search: ");
    final Text searchText = new Text(parent, SWT.BORDER | SWT.SEARCH);
    searchText.setLayoutData(new GridData(GridData.GRAB_HORIZONTAL
        | GridData.HORIZONTAL_ALIGN_FILL));
    createViewer(parent);
    // Set the sorter for the table
    comparator = new MyViewerComparator();
    viewer.setComparator(comparator);

  }

  private 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());
    // Make the selection available to other views
    getSite().setSelectionProvider(viewer);

    // 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);
  }

  public TableViewer getViewer() {
    return viewer;
  }

  // This will create the columns for the table
  private 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();
      }
    });

    // 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 null;
      }

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

  }

  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);
    column.addSelectionListener(getSelectionAdapter(column, colNumber));
    return viewerColumn;
  }

  private SelectionAdapter getSelectionAdapter(final TableColumn column,
      final int index) {
    SelectionAdapter selectionAdapter = new SelectionAdapter() {
      @Override
      public void widgetSelected(SelectionEvent e) {
        comparator.setColumn(index);
        int dir = comparator.getDirection();
        viewer.getTable().setSortDirection(dir);
        viewer.getTable().setSortColumn(column);
        viewer.refresh();
      }
    };
    return selectionAdapter;
  }


/** * Passing the focus request to the viewer's control. */

  public void setFocus() {
    viewer.getControl().setFocus();
  }
}

推荐答案

已

TableItem[] items = viewer.getTable().getItems();

MyObject[] objectsInGui = new MyObject[items.length];
for (int i = 0; i < items.length; i++) {
    objectsInGui[i] = (MyObject) items[i].getData();
}

第二种方法(不是必需的):

The second approach (which wasn't required):

Method getRoot = StructuredViewer.getMethod("getRoot");
getRoot.setAccessible(true);
Method getSortedChildren = StructuredViewer.getMethod("getSortedChildren", Object.class);
getSortedChildren.setAccessible(true);
Object root = getRoot.invoke(viewer);
Object[] objectsInGui = getSortedChildren.invoke(viewer, root);

或使用getFilters()和getComparator()并使用它们进行过滤和排序.

or use getFilters() and getComparator() and filter and sort using them.

这篇关于如何获得JFace的TableViewer的有序元素?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！