| /******************************************************************************* |
| * Copyright (c) 2007, 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 |
| *******************************************************************************/ |
| package org.eclipse.swt.widgets; |
| |
| |
| import org.eclipse.swt.graphics.*; |
| |
| /** |
| * Instances of this class represent input method editors. |
| * These are typically in-line pre-edit text areas that allow |
| * the user to compose characters from Far Eastern languages |
| * such as Japanese, Chinese or Korean. |
| * |
| * <dl> |
| * <dt><b>Styles:</b></dt> |
| * <dd>(none)</dd> |
| * <dt><b>Events:</b></dt> |
| * <dd>ImeComposition</dd> |
| * </dl> |
| * <p> |
| * IMPORTANT: This class is <em>not</em> intended to be subclassed. |
| * </p> |
| * |
| * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> |
| * |
| * @since 3.4 |
| * @noextend This class is not intended to be subclassed by clients. |
| */ |
| public class IME extends Widget { |
| Canvas parent; |
| int caretOffset; |
| int startOffset; |
| int commitCount; |
| String text; |
| int [] ranges; |
| TextStyle [] styles; |
| |
| /** |
| * Prevents uninitialized instances from being created outside the package. |
| */ |
| IME () { |
| } |
| |
| /** |
| * Constructs a new instance of this class given its parent |
| * and a style value describing its behavior and appearance. |
| * <p> |
| * The style value is either one of the style constants defined in |
| * class <code>SWT</code> which is applicable to instances of this |
| * class, or must be built by <em>bitwise OR</em>'ing together |
| * (that is, using the <code>int</code> "|" operator) two or more |
| * of those <code>SWT</code> style constants. The class description |
| * lists the style constants that are applicable to the class. |
| * Style bits are also inherited from superclasses. |
| * </p> |
| * |
| * @param parent a canvas control which will be the parent of the new instance (cannot be null) |
| * @param style the style of control to construct |
| * |
| * @exception IllegalArgumentException <ul> |
| * <li>ERROR_NULL_ARGUMENT - if the parent is null</li> |
| * </ul> |
| * @exception SWTException <ul> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> |
| * <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> |
| * </ul> |
| * |
| * @see Widget#checkSubclass |
| * @see Widget#getStyle |
| */ |
| public IME (Canvas parent, int style) { |
| super (parent, style); |
| this.parent = parent; |
| createWidget (); |
| } |
| |
| void createWidget () { |
| text = ""; |
| startOffset = -1; |
| if (parent.getIME () == null) { |
| parent.setIME (this); |
| } |
| } |
| |
| /** |
| * Returns the offset of the caret from the start of the document. |
| * The caret is within the current composition. |
| * |
| * @return the caret offset |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public int getCaretOffset () { |
| checkWidget (); |
| return startOffset + caretOffset; |
| } |
| |
| /** |
| * Returns the commit count of the composition. This is the |
| * number of characters that have been composed. When the |
| * commit count is equal to the length of the composition |
| * text, then the in-line edit operation is complete. |
| * |
| * @return the commit count |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| * |
| * @see IME#getText |
| */ |
| public int getCommitCount () { |
| checkWidget (); |
| return commitCount; |
| } |
| |
| /** |
| * Returns the offset of the composition from the start of the document. |
| * This is the start offset of the composition within the document and |
| * in not changed by the input method editor itself during the in-line edit |
| * session. |
| * |
| * @return the offset of the composition |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public int getCompositionOffset () { |
| checkWidget (); |
| return startOffset; |
| } |
| |
| /** |
| * Returns the ranges for the style that should be applied during the |
| * in-line edit session. |
| * <p> |
| * The ranges array contains start and end pairs. Each pair refers to |
| * the corresponding style in the styles array. For example, the pair |
| * that starts at ranges[n] and ends at ranges[n+1] uses the style |
| * at styles[n/2] returned by <code>getStyles()</code>. |
| * </p> |
| * @return the ranges for the styles |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| * |
| * @see IME#getStyles |
| */ |
| public int [] getRanges () { |
| checkWidget (); |
| return ranges != null ? ranges : new int [0]; |
| } |
| |
| /** |
| * Returns the styles for the ranges. |
| * <p> |
| * The ranges array contains start and end pairs. Each pair refers to |
| * the corresponding style in the styles array. For example, the pair |
| * that starts at ranges[n] and ends at ranges[n+1] uses the style |
| * at styles[n/2]. |
| * </p> |
| * |
| * @return the ranges for the styles |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| * |
| * @see IME#getRanges |
| */ |
| public TextStyle [] getStyles () { |
| checkWidget (); |
| return styles != null ? styles : new TextStyle [0]; |
| } |
| |
| /** |
| * Returns the composition text. |
| * <p> |
| * The text for an IME is the characters in the widget that |
| * are in the current composition. When the commit count is |
| * equal to the length of the composition text, then the |
| * in-line edit operation is complete. |
| * </p> |
| * |
| * @return the widget text |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public String getText () { |
| checkWidget (); |
| return text; |
| } |
| |
| /** |
| * Returns <code>true</code> if the caret should be wide, and |
| * <code>false</code> otherwise. In some languages, for example |
| * Korean, the caret is typically widened to the width of the |
| * current character in the in-line edit session. |
| * |
| * @return the wide caret state |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public boolean getWideCaret() { |
| return false; |
| } |
| |
| void releaseParent () { |
| super.releaseParent (); |
| if (this == parent.getIME ()) parent.setIME (null); |
| } |
| |
| void releaseWidget () { |
| super.releaseWidget (); |
| parent = null; |
| text = null; |
| styles = null; |
| ranges = null; |
| } |
| |
| /** |
| * Sets the offset of the composition from the start of the document. |
| * This is the start offset of the composition within the document and |
| * in not changed by the input method editor itself during the in-line edit |
| * session but may need to be changed by clients of the IME. For example, |
| * if during an in-line edit operation, a text editor inserts characters |
| * above the IME, then the IME must be informed that the composition |
| * offset has changed. |
| * |
| * @param offset the offset of the composition |
| * |
| * @exception SWTException <ul> |
| * <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> |
| * <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> |
| * </ul> |
| */ |
| public void setCompositionOffset (int offset) { |
| checkWidget (); |
| if (offset < 0) return; |
| if (startOffset != -1) { |
| startOffset = offset; |
| } |
| } |
| |
| } |