Java tutorial
/* * Copyright 2011-2012 Amazon Technologies, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://aws.amazon.com/apache2.0 * * This file is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES * OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and * limitations under the License. */ package com.amazonaws.eclipse.core.ui; import java.util.ArrayList; import java.util.List; import org.eclipse.jface.dialogs.MessageDialog; import org.eclipse.jface.layout.GridDataFactory; import org.eclipse.jface.layout.TableColumnLayout; import org.eclipse.jface.viewers.ColumnWeightData; import org.eclipse.jface.viewers.ISelection; import org.eclipse.jface.viewers.ISelectionChangedListener; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.TableViewer; import org.eclipse.swt.SWT; import org.eclipse.swt.custom.TableEditor; import org.eclipse.swt.graphics.Image; import org.eclipse.swt.graphics.Point; import org.eclipse.swt.graphics.Rectangle; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Display; import org.eclipse.swt.widgets.Event; import org.eclipse.swt.widgets.Listener; 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; import com.amazonaws.eclipse.core.AwsToolkitCore; /** * Simple table dialog to allow use user to enter multiple values for an * attribute. */ public class MultiValueEditorDialog extends MessageDialog { private static final String NEW_VALUE = "<new value>"; private boolean editLocked = false; private int lockedRowIndex = -1; protected final List<String> values = new ArrayList<String>(); protected String columnText = "Attributes"; public List<String> getValues() { return this.values; } protected TableViewer tableViewer; /** * Default constructor provides "OK" and "Cancel" buttons with an AWS logo. */ public MultiValueEditorDialog(final Shell parentShell) { super(parentShell, "Edit values", AwsToolkitCore.getDefault().getImageRegistry().get(AwsToolkitCore.IMAGE_AWS_ICON), "", MessageDialog.NONE, new String[] { "OK", "Cancel" }, 0); } /** * Full featured constructor from {@link MessageDialog} */ public MultiValueEditorDialog(Shell parentShell, String dialogTitle, Image dialogTitleImage, String dialogMessage, int dialogImageType, String[] dialogButtonLabels, int defaultIndex) { super(parentShell, dialogTitle, dialogTitleImage, dialogMessage, dialogImageType, dialogButtonLabels, defaultIndex); } @Override protected boolean isResizable() { return true; } @Override protected Control createDialogArea(final Composite parent) { Composite composite = new Composite(parent, SWT.None); GridDataFactory.fillDefaults().grab(true, true).span(2, 1).applyTo(composite); TableColumnLayout layout = new TableColumnLayout(); composite.setLayout(layout); this.tableViewer = new TableViewer(composite); this.tableViewer.getTable().setHeaderVisible(true); TableColumn tableColumn = new TableColumn(this.tableViewer.getTable(), SWT.NONE); tableColumn.setText(columnText); layout.setColumnData(tableColumn, new ColumnWeightData(100)); this.tableViewer.setContentProvider(new AbstractTableContentProvider() { @Override public Object[] getElements(final Object inputElement) { Object[] rowsPlusNew = new Object[MultiValueEditorDialog.this.values.size() + 1]; MultiValueEditorDialog.this.values.toArray(rowsPlusNew); rowsPlusNew[rowsPlusNew.length - 1] = NEW_VALUE; return rowsPlusNew; } }); this.tableViewer.setLabelProvider(new AbstractTableLabelProvider() { @Override public String getColumnText(final Object element, final int columnIndex) { return (String) element; } }); final Table table = this.tableViewer.getTable(); final TableEditor editor = new TableEditor(table); editor.horizontalAlignment = SWT.LEFT; editor.grabHorizontal = true; table.addListener(SWT.MouseUp, new Listener() { public void handleEvent(final Event event) { Rectangle clientArea = table.getClientArea(); Point pt = new Point(event.x, event.y); int index = table.getTopIndex(); while (index < table.getItemCount()) { boolean visible = false; final TableItem item = table.getItem(index); // Only one column, but loop is here for completeness for (int i = 0; i < table.getColumnCount(); i++) { Rectangle rect = item.getBounds(i); if (rect.contains(pt)) { final int column = i; final Text text = new Text(table, SWT.NONE); final int idx = index; if (isRowUneditable(idx)) { return; } Listener textListener = new Listener() { public void handleEvent(final Event e) { if (e.type == SWT.Traverse && e.detail == SWT.TRAVERSE_ESCAPE) { /* Skip data validation and dispose the text editor */ text.dispose(); e.doit = false; return; } else if (e.type == SWT.Traverse && e.detail != SWT.TRAVERSE_RETURN) { /* No-op for keys other than escape or return. */ return; } else { /* For all other events, we first validate the data */ if (!validateAttributeValue(text.getText())) { lockTableEditor(idx); return; } /* First unlock everything */ unlockTableEditor(); /* Then we handle different events */ if (e.type == SWT.FocusOut) { modifyValue(item, column, idx, text); text.dispose(); } else if (e.type == SWT.Traverse && e.detail == SWT.TRAVERSE_RETURN) { modifyValue(item, column, idx, text); } else if (e.type == SWT.Modify) { /* No-op */ } } } }; text.addListener(SWT.FocusOut, textListener); text.addListener(SWT.Traverse, textListener); text.addListener(SWT.Modify, textListener); editor.setEditor(text, item, i); text.setText(item.getText(i)); text.selectAll(); text.setFocus(); return; } if (!visible && rect.intersects(clientArea)) { visible = true; } } if (!visible) { return; } index++; } } }); /* Suppress changing to other table rows when the editor is locked. */ this.tableViewer.addSelectionChangedListener(new ISelectionChangedListener() { private boolean update = true; private ISelection lastSelection; public void selectionChanged(SelectionChangedEvent event) { if (update && isLocked()) { update = false; // avoid infinite loop tableViewer.setSelection(lastSelection); update = true; } else if (!isLocked()) { lastSelection = event.getSelection(); } } }); this.tableViewer.setInput(values.size()); this.tableViewer.getTable().getItem(this.values.size()) .setForeground(Display.getDefault().getSystemColor(SWT.COLOR_DARK_GRAY)); return composite; } /** * Called when a value in the list is modified. */ protected void modifyValue(final TableItem item, final int column, final int index, final Text text) { String newValue = text.getText(); if (newValue.length() == 0) { if (index < this.values.size()) { this.values.remove(index); } this.tableViewer.refresh(); } else { item.setText(column, newValue); if (index == item.getParent().getItemCount() - 1) { this.values.add(newValue); this.tableViewer.refresh(); item.setForeground(Display.getDefault().getSystemColor(SWT.COLOR_BLACK)); this.tableViewer.getTable().getItem(this.values.size()) .setForeground(Display.getDefault().getSystemColor(SWT.COLOR_DARK_GRAY)); } else { this.values.set(index, newValue); } } } /** * Base class always returns true when validating the data. */ protected boolean validateAttributeValue(String attributeValue) { return true; } /** * Add a customized suffix for the column text. */ protected void addColumnTextDescription(String columnTextSuffix) { this.columnText = this.columnText + " " + columnTextSuffix; } /** * @param index * The index of the locked row. */ protected void lockTableEditor(int index) { editLocked = true; lockedRowIndex = index; this.getButton(0).setEnabled(false); this.getButtonBar().update(); } protected void unlockTableEditor() { editLocked = false; lockedRowIndex = -1; this.getButton(0).setEnabled(true); this.getButtonBar().update(); } private boolean isLocked() { return editLocked; } private boolean isRowUneditable(int index) { return editLocked && index != lockedRowIndex; } }