Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2009 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation * Tom Schindl <tom.schindl@bestsolution.at> - bugfix in 174739 * Ken Wenzel - adaption to CCombo *******************************************************************************/ package net.enilink.commons.ui.jface.table; import java.text.MessageFormat; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.viewers.CellEditor; import org.eclipse.jface.viewers.IBaseLabelProvider; import org.eclipse.jface.viewers.IContentProvider; import org.eclipse.jface.viewers.ILabelProvider; import org.eclipse.jface.viewers.IStructuredContentProvider; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.viewers.StructuredSelection; import org.eclipse.jface.viewers.Viewer; import org.eclipse.jface.viewers.ViewerComparator; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.CCombo; import org.eclipse.swt.events.FocusAdapter; import org.eclipse.swt.events.FocusEvent; import org.eclipse.swt.events.FocusListener; import org.eclipse.swt.events.KeyAdapter; import org.eclipse.swt.events.KeyEvent; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.TraverseEvent; import org.eclipse.swt.events.TraverseListener; import org.eclipse.swt.graphics.GC; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import net.enilink.commons.ui.jface.viewers.CComboViewer; /** * A cell editor that presents a list of items in a combo box. */ public class CComboBoxCellEditor extends CellEditor { private IBaseLabelProvider labelProvider; private IContentProvider contentProvider; private ViewerComparator viewerComparator; /** * The list of items to present in the combo box. */ private Object[] items; /** * The the selected item. */ protected Object selection; /** * The custom combo box control. */ protected CCombo comboBox; /** * The combo box viewer */ protected CComboViewer viewer; private Object input; /** * Default ComboBoxCellEditor style */ private static final int defaultStyle = SWT.NONE; /** * Creates a new cell editor with no control and no st of choices. * Initially, the cell editor has no cell validator. * * @see CellEditor#setStyle * @see CellEditor#create * @see CComboBoxCellEditor#setItems * @see CellEditor#dispose */ public CComboBoxCellEditor() { setStyle(defaultStyle); } /** * Creates a new cell editor with a combo containing the given list of * choices and parented under the given control. The cell editor value is * the zero-based index of the selected item. Initially, the cell editor has * no cell validator and the first item in the list is selected. * * @param parent * the parent control * @param items * the list of strings for the combo box * @param labelProvider * the label provider of the comboviewer * @param style * the style bits */ public CComboBoxCellEditor(Composite parent, Object[] items, IBaseLabelProvider labelProvider, int style) { super(parent, style); this.labelProvider = labelProvider; setItems(items); } /** * Creates a new cell editor with a combo containing the given list of * choices and parented under the given control. The cell editor value is * the zero-based index of the selected item. Initially, the cell editor has * no cell validator and the first item in the list is selected. * * @param parent * the parent control * @param items * the list of strings for the combo box * @param style * the style bits */ public CComboBoxCellEditor(Composite parent, ILabelProvider labelProvider, IContentProvider contentProvider, int style) { setStyle(style); this.labelProvider = labelProvider; this.contentProvider = contentProvider; create(parent); } /** * Returns the list of choices for the combo box * * @return the list of choices for the combo box */ public Object[] getItems() { return this.items; } /** * Sets the list of choices for the combo box * * @param items * the list of choices for the combo box */ public void setItems(Object[] items) { Assert.isNotNull(items); this.items = items; populateComboBoxItems(); } /** * Sets the list of choices for the combo box * * @param items * the list of choices for the combo box */ public void setInput(Object input) { this.input = input; if (viewer != null) { viewer.setInput(input); setValueValid(true); selection = null; } } protected FocusListener createFocusListener() { return new FocusAdapter() { public void focusLost(FocusEvent e) { CComboBoxCellEditor.this.focusLost(); } }; } /* * (non-Javadoc) Method declared on CellEditor. */ protected Control createControl(Composite parent) { comboBox = new CCombo(parent, getStyle()); comboBox.setFont(parent.getFont()); comboBox.addKeyListener(new KeyAdapter() { // hook key pressed - see PR 14201 public void keyPressed(KeyEvent e) { keyReleaseOccured(e); } }); comboBox.addSelectionListener(new SelectionAdapter() { public void widgetDefaultSelected(SelectionEvent event) { applyEditorValueAndDeactivate(); } public void widgetSelected(SelectionEvent event) { selection = ((IStructuredSelection) viewer.getSelection()).getFirstElement(); } }); comboBox.addTraverseListener(new TraverseListener() { public void keyTraversed(TraverseEvent e) { if (e.detail == SWT.TRAVERSE_ESCAPE || e.detail == SWT.TRAVERSE_RETURN) { e.doit = false; } } }); FocusListener focusListener = createFocusListener(); if (focusListener != null) { comboBox.addFocusListener(focusListener); } viewer = new CComboViewer(comboBox); if (contentProvider == null) { contentProvider = new IStructuredContentProvider() { public void dispose() { } public void inputChanged(Viewer viewer, Object oldInput, Object newInput) { } public Object[] getElements(Object inputElement) { if (inputElement instanceof Object[]) { return (Object[]) inputElement; } return new Object[0]; } }; } viewer.setContentProvider(contentProvider); if (labelProvider != null) { viewer.setLabelProvider(labelProvider); } if (viewerComparator != null) { viewer.setComparator(viewerComparator); } return comboBox; } protected void selectionChanged() { } public void setLabelProvider(IBaseLabelProvider labelProvider) { this.labelProvider = labelProvider; if (viewer != null && labelProvider != null) { viewer.setLabelProvider(labelProvider); } } public void setContentProvider(IContentProvider contentProvider) { this.contentProvider = contentProvider; if (viewer != null && contentProvider != null) { viewer.setContentProvider(contentProvider); } } public void setViewerComparator(ViewerComparator viewerComparator) { this.viewerComparator = viewerComparator; if (viewer != null && viewerComparator != null) { viewer.setComparator(viewerComparator); } } /** * The <code>ComboBoxCellEditor</code> implementation of this * <code>CellEditor</code> framework method returns the current selection. * * @return the current selection */ protected Object doGetValue() { return selection; } /* * (non-Javadoc) Method declared on CellEditor. */ protected void doSetFocus() { comboBox.setFocus(); } /** * The <code>ComboBoxCellEditor</code> implementation of this * <code>CellEditor</code> framework method sets the minimum width of the * cell. The minimum width is 10 characters if <code>comboBox</code> is * not <code>null</code> or <code>disposed</code> eles it is 60 pixels * to make sure the arrow button and some text is visible. The list of * CCombo will be wide enough to show its longest item. */ public LayoutData getLayoutData() { LayoutData layoutData = super.getLayoutData(); if (comboBox == null || comboBox.isDisposed()) { layoutData.minimumWidth = 60; } else { // make the comboBox 10 characters wide GC gc = new GC(comboBox); layoutData.minimumWidth = (gc.getFontMetrics().getAverageCharWidth() * 10) + 10; gc.dispose(); } return layoutData; } /** * The <code>ComboBoxCellEditor</code> implementation of this * <code>CellEditor</code> framework method accepts a zero-based index of * a selection. * * @param value * the zero-based index of the selection wrapped as an * <code>Integer</code> */ protected void doSetValue(Object value) { Assert.isTrue(viewer != null); if (value != null) { viewer.setSelection(new StructuredSelection(value), true); } else { viewer.setSelection(StructuredSelection.EMPTY); } selection = value; } /** * Updates the list of choices for the combo box for the current control. */ private void populateComboBoxItems() { if (viewer != null && items != null) { viewer.setInput(items); setValueValid(true); selection = null; } } /** * Applies the currently selected value and deactiavates the cell editor */ void applyEditorValueAndDeactivate() { // must set the selection before getting value selection = ((IStructuredSelection) viewer.getSelection()).getFirstElement(); Object newValue = doGetValue(); markDirty(); boolean isValid = isCorrect(newValue); setValueValid(isValid); if (!isValid) { // Only format if the selection is valid if (selection != null) { // try to insert the current value into the error message. setErrorMessage(MessageFormat.format(getErrorMessage(), new Object[] { selection })); } else { // Since we don't have a valid selection, assume we're using an // 'edit' // combo so format using its text value setErrorMessage(MessageFormat.format(getErrorMessage(), new Object[] { comboBox.getText() })); } } fireApplyEditorValue(); deactivate(); } /* * (non-Javadoc) * * @see org.eclipse.jface.viewers.CellEditor#focusLost() */ protected void focusLost() { if (isActivated()) { applyEditorValueAndDeactivate(); } } /* * (non-Javadoc) * * @see org.eclipse.jface.viewers.CellEditor#keyReleaseOccured(org.eclipse.swt.events.KeyEvent) */ protected void keyReleaseOccured(KeyEvent keyEvent) { if (keyEvent.character == '\u001b') { // Escape character fireCancelEditor(); } else if (keyEvent.character == '\t') { // tab key applyEditorValueAndDeactivate(); } } }