Mercurial > projects > dwt-win
annotate dwt/events/TraverseEvent.d @ 212:ab60f3309436
reverted the char[] to String and use the an alias.
| author | Frank Benoit <benoit@tionex.de> |
|---|---|
| date | Mon, 05 May 2008 00:12:38 +0200 |
| parents | bef1ed4ebc50 |
| children | fd9c62a2998e |
| rev | line source |
|---|---|
| 0 | 1 /******************************************************************************* |
| 2 * Copyright (c) 2000, 2006 IBM Corporation and others. | |
| 3 * All rights reserved. This program and the accompanying materials | |
| 4 * are made available under the terms of the Eclipse Public License v1.0 | |
| 5 * which accompanies this distribution, and is available at | |
| 6 * http://www.eclipse.org/legal/epl-v10.html | |
| 7 * | |
| 8 * Contributors: | |
| 9 * IBM Corporation - initial API and implementation | |
| 10 * Port to the D programming language: | |
| 11 * Frank Benoit <benoit@tionex.de> | |
| 12 *******************************************************************************/ | |
| 13 module dwt.events.TraverseEvent; | |
| 14 | |
| 15 | |
| 16 import dwt.widgets.Event; | |
| 17 import dwt.events.KeyEvent; | |
| 18 | |
| 19 import tango.text.convert.Format; | |
|
212
ab60f3309436
reverted the char[] to String and use the an alias.
Frank Benoit <benoit@tionex.de>
parents:
86
diff
changeset
|
20 import dwt.dwthelper.utils; |
|
ab60f3309436
reverted the char[] to String and use the an alias.
Frank Benoit <benoit@tionex.de>
parents:
86
diff
changeset
|
21 |
| 0 | 22 /** |
| 23 * Instances of this class are sent as a result of | |
| 24 * widget traversal actions. | |
| 25 * <p> | |
| 26 * The traversal event allows fine control over keyboard traversal | |
| 27 * in a control both to implement traversal and override the default | |
| 28 * traversal behavior defined by the system. This is achieved using | |
| 29 * two fields, <code>detail</code> and <code>doit</code>. | |
| 30 * </p><p> | |
| 31 * When a control is traversed, a traverse event is sent. The detail | |
| 32 * describes the type of traversal and the doit field indicates the default | |
| 33 * behavior of the system. For example, when a right arrow key is pressed | |
| 34 * in a text control, the detail field is <code>TRAVERSE_ARROW_NEXT</code> | |
| 35 * and the doit field is <code>false</code>, indicating that the system | |
| 36 * will not traverse to the next tab item and the arrow key will be | |
| 37 * delivered to the text control. If the same key is pressed in a radio | |
| 38 * button, the doit field will be <code>true</code>, indicating that | |
| 39 * traversal is to proceed to the next tab item, possibly another radio | |
| 40 * button in the group and that the arrow key is not to be delivered | |
| 41 * to the radio button. | |
| 42 * </p><p> | |
| 43 * How can the traversal event be used to implement traversal? | |
| 44 * When a tab key is pressed in a canvas, the detail field will be | |
| 45 * <code>TRAVERSE_TAB_NEXT</code> and the doit field will be | |
| 46 * <code>false</code>. The default behavior of the system is to | |
| 47 * provide no traversal for canvas controls. This means that by | |
| 48 * default in a canvas, a key listener will see every key that the | |
| 49 * user types, including traversal keys. To understand why this | |
| 50 * is so, it is important to understand that only the widget implementor | |
| 51 * can decide which traversal is appropriate for the widget. Returning | |
| 52 * to the <code>TRAVERSE_TAB_NEXT</code> example, a text widget implemented | |
| 53 * by a canvas would typically want to use the tab key to insert a | |
| 54 * tab character into the widget. A list widget implementation, on the | |
| 55 * other hand, would like the system default traversal behavior. Using | |
| 56 * only the doit flag, both implementations are possible. The text widget | |
| 57 * implementor sets doit to <code>false</code>, ensuring that the system | |
| 58 * will not traverse and that the tab key will be delivered to key listeners. | |
| 59 * The list widget implementor sets doit to <code>true</code>, indicating | |
| 60 * that the system should perform tab traversal and that the key should not | |
| 61 * be delivered to the list widget. | |
| 62 * </p><p> | |
| 63 * How can the traversal event be used to override system traversal? | |
| 64 * When the return key is pressed in a single line text control, the | |
| 65 * detail field is <code>TRAVERSE_RETURN</code> and the doit field | |
| 66 * is <code>true</code>. This means that the return key will be processed | |
| 67 * by the default button, not the text widget. If the text widget has | |
| 68 * a default selection listener, it will not run because the return key | |
| 69 * will be processed by the default button. Imagine that the text control | |
| 70 * is being used as an in-place editor and return is used to dispose the | |
| 71 * widget. Setting doit to <code>false</code> will stop the system from | |
| 72 * activating the default button but the key will be delivered to the text | |
| 73 * control, running the key and selection listeners for the text. How | |
| 74 * can <code>TRAVERSE_RETURN</code> be implemented so that the default button | |
| 75 * will not be activated and the text widget will not see the return key? | |
| 76 * This is achieved by setting doit to <code>true</code>, and the detail | |
| 77 * to <code>TRAVERSE_NONE</code>. | |
| 78 * </p><p> | |
| 79 * Note: A widget implementor will typically implement traversal using | |
| 80 * only the doit flag to either enable or disable system traversal. | |
| 81 * </p> | |
| 82 * | |
| 83 * @see TraverseListener | |
| 84 */ | |
| 85 | |
| 86 public final class TraverseEvent : KeyEvent { | |
| 87 | |
| 88 /** | |
| 89 * The traversal type. | |
| 90 * <p><ul> | |
| 91 * <li>{@link dwt.DWT#TRAVERSE_NONE}</li> | |
| 92 * <li>{@link dwt.DWT#TRAVERSE_ESCAPE}</li> | |
| 93 * <li>{@link dwt.DWT#TRAVERSE_RETURN}</li> | |
| 94 * <li>{@link dwt.DWT#TRAVERSE_TAB_NEXT}</li> | |
| 95 * <li>{@link dwt.DWT#TRAVERSE_TAB_PREVIOUS}</li> | |
| 96 * <li>{@link dwt.DWT#TRAVERSE_ARROW_NEXT}</li> | |
| 97 * <li>{@link dwt.DWT#TRAVERSE_ARROW_PREVIOUS}</li> | |
| 98 * <li>{@link dwt.DWT#TRAVERSE_MNEMONIC}</li> | |
| 99 * <li>{@link dwt.DWT#TRAVERSE_PAGE_NEXT}</li> | |
| 100 * <li>{@link dwt.DWT#TRAVERSE_PAGE_PREVIOUS}</li> | |
| 101 * </ul></p> | |
| 102 * | |
| 103 * Setting this field will change the type of traversal. | |
| 104 * For example, setting the detail to <code>TRAVERSE_NONE</code> | |
| 105 * causes no traversal action to be taken. | |
| 106 * | |
| 107 * When used in conjunction with the <code>doit</code> field, the | |
| 108 * traversal detail field can be useful when overriding the default | |
| 109 * traversal mechanism for a control. For example, setting the doit | |
| 110 * field to <code>false</code> will cancel the operation and allow | |
| 111 * the traversal key stroke to be delivered to the control. Setting | |
| 112 * the doit field to <code>true</code> indicates that the traversal | |
| 113 * described by the detail field is to be performed. | |
| 114 */ | |
| 115 public int detail; | |
| 116 | |
| 117 //static final long serialVersionUID = 3257565105301239349L; | |
| 118 | |
| 119 /** | |
| 120 * Constructs a new instance of this class based on the | |
| 121 * information in the given untyped event. | |
| 122 * | |
| 123 * @param e the untyped event containing the information | |
| 124 */ | |
| 125 public this(Event e) { | |
| 126 super(e); | |
| 127 this.detail = e.detail; | |
| 128 } | |
| 129 | |
| 130 /** | |
| 131 * Returns a string containing a concise, human-readable | |
| 132 * description of the receiver. | |
| 133 * | |
| 134 * @return a string representation of the event | |
| 135 */ | |
|
212
ab60f3309436
reverted the char[] to String and use the an alias.
Frank Benoit <benoit@tionex.de>
parents:
86
diff
changeset
|
136 public override String toString() { |
| 0 | 137 return Format( "{} detail={}}", super.toString[ 0 .. $-2 ], detail ); |
| 138 } | |
| 139 } |