1 /* 2 * Copyright (c) 1997, 2003, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package javax.accessibility; 27 28 import java.awt.*; 29 import java.awt.event.*; 30 31 /** 32 * The AccessibleComponent interface should be supported by any object 33 * that is rendered on the screen. This interface provides the standard 34 * mechanism for an assistive technology to determine and set the 35 * graphical representation of an object. Applications can determine 36 * if an object supports the AccessibleComponent interface by first 37 * obtaining its AccessibleContext 38 * and then calling the 39 * {@link AccessibleContext#getAccessibleComponent} method. 40 * If the return value is not null, the object supports this interface. 41 * 42 * @see Accessible 43 * @see Accessible#getAccessibleContext 44 * @see AccessibleContext 45 * @see AccessibleContext#getAccessibleComponent 46 * 47 * @author Peter Korn 48 * @author Hans Muller 49 * @author Willie Walker 50 */ 51 public interface AccessibleComponent { 52 53 /** 54 * Gets the background color of this object. 55 * 56 * @return the background color, if supported, of the object; 57 * otherwise, null 58 * @see #setBackground 59 */ getBackground()60 public Color getBackground(); 61 62 /** 63 * Sets the background color of this object. 64 * 65 * @param c the new Color for the background 66 * @see #setBackground 67 */ setBackground(Color c)68 public void setBackground(Color c); 69 70 /** 71 * Gets the foreground color of this object. 72 * 73 * @return the foreground color, if supported, of the object; 74 * otherwise, null 75 * @see #setForeground 76 */ getForeground()77 public Color getForeground(); 78 79 /** 80 * Sets the foreground color of this object. 81 * 82 * @param c the new Color for the foreground 83 * @see #getForeground 84 */ setForeground(Color c)85 public void setForeground(Color c); 86 87 /** 88 * Gets the Cursor of this object. 89 * 90 * @return the Cursor, if supported, of the object; otherwise, null 91 * @see #setCursor 92 */ getCursor()93 public Cursor getCursor(); 94 95 /** 96 * Sets the Cursor of this object. 97 * 98 * @param cursor the new Cursor for the object 99 * @see #getCursor 100 */ setCursor(Cursor cursor)101 public void setCursor(Cursor cursor); 102 103 /** 104 * Gets the Font of this object. 105 * 106 * @return the Font,if supported, for the object; otherwise, null 107 * @see #setFont 108 */ getFont()109 public Font getFont(); 110 111 /** 112 * Sets the Font of this object. 113 * 114 * @param f the new Font for the object 115 * @see #getFont 116 */ setFont(Font f)117 public void setFont(Font f); 118 119 /** 120 * Gets the FontMetrics of this object. 121 * 122 * @param f the Font 123 * @return the FontMetrics, if supported, the object; otherwise, null 124 * @see #getFont 125 */ getFontMetrics(Font f)126 public FontMetrics getFontMetrics(Font f); 127 128 /** 129 * Determines if the object is enabled. Objects that are enabled 130 * will also have the AccessibleState.ENABLED state set in their 131 * AccessibleStateSets. 132 * 133 * @return true if object is enabled; otherwise, false 134 * @see #setEnabled 135 * @see AccessibleContext#getAccessibleStateSet 136 * @see AccessibleState#ENABLED 137 * @see AccessibleStateSet 138 */ isEnabled()139 public boolean isEnabled(); 140 141 /** 142 * Sets the enabled state of the object. 143 * 144 * @param b if true, enables this object; otherwise, disables it 145 * @see #isEnabled 146 */ setEnabled(boolean b)147 public void setEnabled(boolean b); 148 149 /** 150 * Determines if the object is visible. Note: this means that the 151 * object intends to be visible; however, it may not be 152 * showing on the screen because one of the objects that this object 153 * is contained by is currently not visible. To determine if an object is 154 * showing on the screen, use isShowing(). 155 * <p>Objects that are visible will also have the 156 * AccessibleState.VISIBLE state set in their AccessibleStateSets. 157 * 158 * @return true if object is visible; otherwise, false 159 * @see #setVisible 160 * @see AccessibleContext#getAccessibleStateSet 161 * @see AccessibleState#VISIBLE 162 * @see AccessibleStateSet 163 */ isVisible()164 public boolean isVisible(); 165 166 /** 167 * Sets the visible state of the object. 168 * 169 * @param b if true, shows this object; otherwise, hides it 170 * @see #isVisible 171 */ setVisible(boolean b)172 public void setVisible(boolean b); 173 174 /** 175 * Determines if the object is showing. This is determined by checking 176 * the visibility of the object and its ancestors. 177 * Note: this 178 * will return true even if the object is obscured by another (for example, 179 * it is underneath a menu that was pulled down). 180 * 181 * @return true if object is showing; otherwise, false 182 */ isShowing()183 public boolean isShowing(); 184 185 /** 186 * Checks whether the specified point is within this object's bounds, 187 * where the point's x and y coordinates are defined to be relative to the 188 * coordinate system of the object. 189 * 190 * @param p the Point relative to the coordinate system of the object 191 * @return true if object contains Point; otherwise false 192 * @see #getBounds 193 */ contains(Point p)194 public boolean contains(Point p); 195 196 /** 197 * Returns the location of the object on the screen. 198 * 199 * @return the location of the object on screen; null if this object 200 * is not on the screen 201 * @see #getBounds 202 * @see #getLocation 203 */ getLocationOnScreen()204 public Point getLocationOnScreen(); 205 206 /** 207 * Gets the location of the object relative to the parent in the form 208 * of a point specifying the object's top-left corner in the screen's 209 * coordinate space. 210 * 211 * @return An instance of Point representing the top-left corner of the 212 * object's bounds in the coordinate space of the screen; null if 213 * this object or its parent are not on the screen 214 * @see #getBounds 215 * @see #getLocationOnScreen 216 */ getLocation()217 public Point getLocation(); 218 219 /** 220 * Sets the location of the object relative to the parent. 221 * @param p the new position for the top-left corner 222 * @see #getLocation 223 */ setLocation(Point p)224 public void setLocation(Point p); 225 226 /** 227 * Gets the bounds of this object in the form of a Rectangle object. 228 * The bounds specify this object's width, height, and location 229 * relative to its parent. 230 * 231 * @return A rectangle indicating this component's bounds; null if 232 * this object is not on the screen. 233 * @see #contains 234 */ getBounds()235 public Rectangle getBounds(); 236 237 /** 238 * Sets the bounds of this object in the form of a Rectangle object. 239 * The bounds specify this object's width, height, and location 240 * relative to its parent. 241 * 242 * @param r rectangle indicating this component's bounds 243 * @see #getBounds 244 */ setBounds(Rectangle r)245 public void setBounds(Rectangle r); 246 247 /** 248 * Returns the size of this object in the form of a Dimension object. 249 * The height field of the Dimension object contains this object's 250 * height, and the width field of the Dimension object contains this 251 * object's width. 252 * 253 * @return A Dimension object that indicates the size of this component; 254 * null if this object is not on the screen 255 * @see #setSize 256 */ getSize()257 public Dimension getSize(); 258 259 /** 260 * Resizes this object so that it has width and height. 261 * 262 * @param d The dimension specifying the new size of the object. 263 * @see #getSize 264 */ setSize(Dimension d)265 public void setSize(Dimension d); 266 267 /** 268 * Returns the Accessible child, if one exists, contained at the local 269 * coordinate Point. 270 * 271 * @param p The point relative to the coordinate system of this object. 272 * @return the Accessible, if it exists, at the specified location; 273 * otherwise null 274 */ getAccessibleAt(Point p)275 public Accessible getAccessibleAt(Point p); 276 277 /** 278 * Returns whether this object can accept focus or not. Objects that 279 * can accept focus will also have the AccessibleState.FOCUSABLE state 280 * set in their AccessibleStateSets. 281 * 282 * @return true if object can accept focus; otherwise false 283 * @see AccessibleContext#getAccessibleStateSet 284 * @see AccessibleState#FOCUSABLE 285 * @see AccessibleState#FOCUSED 286 * @see AccessibleStateSet 287 */ isFocusTraversable()288 public boolean isFocusTraversable(); 289 290 /** 291 * Requests focus for this object. If this object cannot accept focus, 292 * nothing will happen. Otherwise, the object will attempt to take 293 * focus. 294 * @see #isFocusTraversable 295 */ requestFocus()296 public void requestFocus(); 297 298 /** 299 * Adds the specified focus listener to receive focus events from this 300 * component. 301 * 302 * @param l the focus listener 303 * @see #removeFocusListener 304 */ addFocusListener(FocusListener l)305 public void addFocusListener(FocusListener l); 306 307 /** 308 * Removes the specified focus listener so it no longer receives focus 309 * events from this component. 310 * 311 * @param l the focus listener 312 * @see #addFocusListener 313 */ removeFocusListener(FocusListener l)314 public void removeFocusListener(FocusListener l); 315 } 316