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annotate org.eclipse.swt.gtk.linux.x86/src/org/eclipse/swt/layout/FormLayout.d @ 125:c43718956f21 default tip
Updated the snippets status.
| author | Jacob Carlborg <doob@me.com> |
|---|---|
| date | Thu, 11 Aug 2011 19:55:14 +0200 |
| parents | 536e43f63c81 |
| children |
| rev | line source |
|---|---|
| 25 | 1 /******************************************************************************* |
| 2 * Copyright (c) 2000, 2008 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 org.eclipse.swt.layout.FormLayout; | |
| 14 | |
| 15 import org.eclipse.swt.layout.FormAttachment; | |
| 16 import org.eclipse.swt.layout.FormData; | |
| 17 import org.eclipse.swt.SWT; | |
| 18 import org.eclipse.swt.graphics.Point; | |
| 19 import org.eclipse.swt.graphics.Rectangle; | |
| 20 import org.eclipse.swt.widgets.Control; | |
| 21 import org.eclipse.swt.widgets.Layout; | |
| 22 import org.eclipse.swt.widgets.Composite; | |
| 23 import org.eclipse.swt.widgets.Scrollable; | |
| 24 | |
| 48 | 25 import java.lang.all; |
| 25 | 26 |
| 27 /** | |
| 28 * Instances of this class control the position and size of the | |
| 29 * children of a composite control by using <code>FormAttachments</code> | |
| 30 * to optionally configure the left, top, right and bottom edges of | |
| 31 * each child. | |
| 32 * <p> | |
| 33 * The following example code creates a <code>FormLayout</code> and then sets | |
| 34 * it into a <code>Shell</code>: | |
| 35 * <pre> | |
| 36 * Display display = new Display (); | |
| 37 * Shell shell = new Shell(display); | |
| 38 * FormLayout layout = new FormLayout(); | |
| 39 * layout.marginWidth = 3; | |
| 40 * layout.marginHeight = 3; | |
| 41 * shell.setLayout(layout); | |
| 42 * </pre> | |
| 43 * </p> | |
| 44 * <p> | |
| 45 * To use a <code>FormLayout</code>, create a <code>FormData</code> with | |
| 46 * <code>FormAttachment</code> for each child of <code>Composite</code>. | |
| 47 * The following example code attaches <code>button1</code> to the top | |
| 48 * and left edge of the composite and <code>button2</code> to the right | |
| 49 * edge of <code>button1</code> and the top and right edges of the | |
| 50 * composite: | |
| 51 * <pre> | |
| 52 * FormData data1 = new FormData(); | |
| 53 * data1.left = new FormAttachment(0, 0); | |
| 54 * data1.top = new FormAttachment(0, 0); | |
| 55 * button1.setLayoutData(data1); | |
| 56 * FormData data2 = new FormData(); | |
| 57 * data2.left = new FormAttachment(button1); | |
| 58 * data2.top = new FormAttachment(0, 0); | |
| 59 * data2.right = new FormAttachment(100, 0); | |
| 60 * button2.setLayoutData(data2); | |
| 61 * </pre> | |
| 62 * </p> | |
| 63 * <p> | |
| 64 * Each side of a child control can be attached to a position in the parent | |
| 65 * composite, or to other controls within the <code>Composite</code> by | |
| 66 * creating instances of <code>FormAttachment</code> and setting them into | |
| 67 * the top, bottom, left, and right fields of the child's <code>FormData</code>. | |
| 68 * </p> | |
| 69 * <p> | |
| 70 * If a side is not given an attachment, it is defined as not being attached | |
| 71 * to anything, causing the child to remain at its preferred size. If a child | |
| 72 * is given no attachment on either the left or the right or top or bottom, it is | |
| 73 * automatically attached to the left and top of the composite respectively. | |
| 74 * The following code positions <code>button1</code> and <code>button2</code> | |
| 75 * but relies on default attachments: | |
| 76 * <pre> | |
| 77 * FormData data2 = new FormData(); | |
| 78 * data2.left = new FormAttachment(button1); | |
| 79 * data2.right = new FormAttachment(100, 0); | |
| 80 * button2.setLayoutData(data2); | |
| 81 * </pre> | |
| 82 * </p> | |
| 83 * <p> | |
| 84 * IMPORTANT: Do not define circular attachments. For example, do not attach | |
| 85 * the right edge of <code>button1</code> to the left edge of <code>button2</code> | |
| 86 * and then attach the left edge of <code>button2</code> to the right edge of | |
| 87 * <code>button1</code>. This will over constrain the layout, causing undefined | |
| 88 * behavior. The algorithm will terminate, but the results are undefined. | |
| 89 * </p> | |
| 90 * | |
| 91 * @see FormData | |
| 92 * @see FormAttachment | |
| 93 * @see <a href="http://www.eclipse.org/swt/snippets/#formlayout">FormLayout snippets</a> | |
| 94 * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: LayoutExample</a> | |
| 95 * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> | |
| 96 * | |
| 97 * @since 2.0 | |
| 98 */ | |
| 99 public final class FormLayout : Layout { | |
| 100 | |
| 101 /** | |
| 102 * marginWidth specifies the number of pixels of horizontal margin | |
| 103 * that will be placed along the left and right edges of the layout. | |
| 104 * | |
| 105 * The default value is 0. | |
| 106 */ | |
| 107 public int marginWidth = 0; | |
| 108 | |
| 109 /** | |
| 110 * marginHeight specifies the number of pixels of vertical margin | |
| 111 * that will be placed along the top and bottom edges of the layout. | |
| 112 * | |
| 113 * The default value is 0. | |
| 114 */ | |
| 115 public int marginHeight = 0; | |
| 116 | |
| 117 | |
| 118 /** | |
| 119 * marginLeft specifies the number of pixels of horizontal margin | |
| 120 * that will be placed along the left edge of the layout. | |
| 121 * | |
| 122 * The default value is 0. | |
| 123 * | |
| 124 * @since 3.1 | |
| 125 */ | |
| 126 public int marginLeft = 0; | |
| 127 | |
| 128 /** | |
| 129 * marginTop specifies the number of pixels of vertical margin | |
| 130 * that will be placed along the top edge of the layout. | |
| 131 * | |
| 132 * The default value is 0. | |
| 133 * | |
| 134 * @since 3.1 | |
| 135 */ | |
| 136 public int marginTop = 0; | |
| 137 | |
| 138 /** | |
| 139 * marginRight specifies the number of pixels of horizontal margin | |
| 140 * that will be placed along the right edge of the layout. | |
| 141 * | |
| 142 * The default value is 0. | |
| 143 * | |
| 144 * @since 3.1 | |
| 145 */ | |
| 146 public int marginRight = 0; | |
| 147 | |
| 148 /** | |
| 149 * marginBottom specifies the number of pixels of vertical margin | |
| 150 * that will be placed along the bottom edge of the layout. | |
| 151 * | |
| 152 * The default value is 0. | |
| 153 * | |
| 154 * @since 3.1 | |
| 155 */ | |
| 156 public int marginBottom = 0; | |
| 157 | |
| 158 /** | |
| 159 * spacing specifies the number of pixels between the edge of one control | |
| 160 * and the edge of its neighbouring control. | |
| 161 * | |
| 162 * The default value is 0. | |
| 163 * | |
| 164 * @since 3.0 | |
| 165 */ | |
| 166 public int spacing = 0; | |
| 167 | |
| 168 /** | |
| 169 * Constructs a new instance of this class. | |
| 170 */ | |
| 171 public this () { | |
| 172 } | |
| 173 | |
| 174 /* | |
| 175 * Computes the preferred height of the form with | |
| 176 * respect to the preferred height of the control. | |
| 177 * | |
| 178 * Given that the equations for top (T) and bottom (B) | |
| 179 * of the control in terms of the height of the form (X) | |
| 180 * are: | |
| 181 * T = AX + B | |
| 182 * B = CX + D | |
| 183 * | |
| 184 * The equation for the height of the control (H) | |
| 185 * is bottom (B) minus top (T) or (H = B - T) or: | |
| 186 * | |
| 187 * H = (CX + D) - (AX + B) | |
| 188 * | |
| 189 * Solving for (X), the height of the form, we get: | |
| 190 * | |
| 191 * X = (H + B - D) / (C - A) | |
| 192 * | |
| 193 * When (A = C), (C - A = 0) and the equation has no | |
| 194 * solution for X. This is a special case meaning that | |
| 195 * the control does not constrain the height of the | |
| 196 * form. In this case, we need to arbitrarily define | |
| 197 * the height of the form (X): | |
| 198 * | |
| 199 * Case 1: A = C, A = 0, C = 0 | |
| 200 * | |
| 201 * Let X = D, the distance from the top of the form | |
| 202 * to the bottom edge of the control. In this case, | |
| 203 * the control was attached to the top of the form | |
| 204 * and the form needs to be large enough to show the | |
| 205 * bottom edge of the control. | |
| 206 * | |
| 207 * Case 2: A = C, A = 1, C = 1 | |
| 208 * | |
| 209 * Let X = -B, the distance from the bottom of the | |
| 210 * form to the top edge of the control. In this case, | |
| 211 * the control was attached to the bottom of the form | |
| 212 * and the only way that the control would be visible | |
| 213 * is if the offset is negative. If the offset is | |
| 214 * positive, there is no possible height for the form | |
| 215 * that will show the control as it will always be | |
| 216 * below the bottom edge of the form. | |
| 217 * | |
| 218 * Case 3: A = C, A !is 0, C !is 0 and A !is 1, C !is 0 | |
| 219 * | |
| 220 * Let X = D / (1 - C), the distance from the top of the | |
| 221 * form to the bottom edge of the control. In this case, | |
| 222 * since C is not 0 or 1, it must be a fraction, U / V. | |
| 223 * The offset D is the distance from CX to the bottom edge | |
| 224 * of the control. This represents a fraction of the form | |
| 225 * (1 - C)X. Since the height of a fraction of the form is | |
| 226 * known, the height of the entire form can be found by setting | |
| 227 * (1 - C)X = D. We solve this equation for X in terms of U | |
| 228 * and V, giving us X = (U * D) / (U - V). Similarly, if the | |
| 229 * offset D is negative, the control is positioned above CX. | |
| 230 * The offset -B is the distance from the top edge of the control | |
| 231 * to CX. We can find the height of the entire form by setting | |
| 232 * CX = -B. Solving in terms of U and V gives us X = (-B * V) / U. | |
| 233 */ | |
| 234 int computeHeight (Control control, FormData data, bool flushCache) { | |
| 235 FormAttachment top = data.getTopAttachment (control, spacing, flushCache); | |
| 236 FormAttachment bottom = data.getBottomAttachment (control, spacing, flushCache); | |
| 237 FormAttachment height = bottom.minus (top); | |
| 238 if (height.numerator is 0) { | |
| 239 if (bottom.numerator is 0) return bottom.offset; | |
| 240 if (bottom.numerator is bottom.denominator) return -top.offset; | |
| 241 if (bottom.offset <= 0) { | |
| 242 return -top.offset * top.denominator / bottom.numerator; | |
| 243 } | |
| 244 int divider = bottom.denominator - bottom.numerator; | |
| 245 return bottom.denominator * bottom.offset / divider; | |
| 246 } | |
| 247 return height.solveY (data.getHeight (control, flushCache)); | |
| 248 } | |
| 249 | |
| 250 override protected Point computeSize (Composite composite, int wHint, int hHint, bool flushCache) { | |
| 251 Point size = layout (composite, false, 0, 0, wHint, hHint, flushCache); | |
| 252 if (wHint !is SWT.DEFAULT) size.x = wHint; | |
| 253 if (hHint !is SWT.DEFAULT) size.y = hHint; | |
| 254 return size; | |
| 255 } | |
| 256 | |
| 257 override protected bool flushCache (Control control) { | |
| 258 Object data = control.getLayoutData (); | |
| 259 if (data !is null) (cast(FormData) data).flushCache (); | |
| 260 return true; | |
| 261 } | |
| 262 | |
| 263 String getName () { | |
| 264 String string = this.classinfo.name; | |
| 265 int index = string.lastIndexOf('.'); | |
| 266 if (index is -1 ) return string; | |
| 267 return string[ index + 1 .. string.length ]; | |
| 268 } | |
| 269 | |
| 270 /* | |
| 271 * Computes the preferred height of the form with | |
| 272 * respect to the preferred height of the control. | |
| 273 */ | |
| 274 int computeWidth (Control control, FormData data, bool flushCache) { | |
| 275 FormAttachment left = data.getLeftAttachment (control, spacing, flushCache); | |
| 276 FormAttachment right = data.getRightAttachment (control, spacing, flushCache); | |
| 277 FormAttachment width = right.minus (left); | |
| 278 if (width.numerator is 0) { | |
| 279 if (right.numerator is 0) return right.offset; | |
| 280 if (right.numerator is right.denominator) return -left.offset; | |
| 281 if (right.offset <= 0) { | |
| 282 return -left.offset * left.denominator / left.numerator; | |
| 283 } | |
| 284 int divider = right.denominator - right.numerator; | |
| 285 return right.denominator * right.offset / divider; | |
| 286 } | |
| 287 return width.solveY (data.getWidth (control, flushCache)); | |
| 288 } | |
| 289 | |
| 290 override protected void layout (Composite composite, bool flushCache) { | |
| 291 Rectangle rect = composite.getClientArea (); | |
| 292 int x = rect.x + marginLeft + marginWidth; | |
| 293 int y = rect.y + marginTop + marginHeight; | |
| 294 int width = Math.max (0, rect.width - marginLeft - 2 * marginWidth - marginRight); | |
| 295 int height = Math.max (0, rect.height - marginTop - 2 * marginHeight - marginBottom); | |
| 296 layout (composite, true, x, y, width, height, flushCache); | |
| 297 } | |
| 298 | |
| 299 Point layout (Composite composite, bool move, int x, int y, int width, int height, bool flushCache) { | |
| 300 Control [] children = composite.getChildren (); | |
| 301 for (int i=0; i<children.length; i++) { | |
| 302 Control child = children [i]; | |
| 303 FormData data = cast(FormData) child.getLayoutData (); | |
| 304 if (data is null) child.setLayoutData (data = new FormData ()); | |
| 305 if (flushCache) data.flushCache (); | |
| 306 data.cacheLeft = data.cacheRight = data.cacheTop = data.cacheBottom = null; | |
| 307 } | |
| 308 bool [] flush = null; | |
| 309 Rectangle [] bounds = null; | |
| 310 int w = 0, h = 0; | |
| 311 for (int i=0; i<children.length; i++) { | |
| 312 Control child = children [i]; | |
| 313 FormData data = cast(FormData) child.getLayoutData (); | |
| 314 if (width !is SWT.DEFAULT) { | |
| 315 data.needed = false; | |
| 316 FormAttachment left = data.getLeftAttachment (child, spacing, flushCache); | |
| 317 FormAttachment right = data.getRightAttachment (child, spacing, flushCache); | |
| 318 int x1 = left.solveX (width), x2 = right.solveX (width); | |
| 319 if (data.height is SWT.DEFAULT && !data.needed) { | |
| 320 int trim = 0; | |
| 321 //TEMPORARY CODE | |
| 322 if ( auto sa = cast(Scrollable)child) { | |
| 323 Rectangle rect = sa.computeTrim (0, 0, 0, 0); | |
| 324 trim = rect.width; | |
| 325 } else { | |
| 326 trim = child.getBorderWidth () * 2; | |
| 327 } | |
| 328 data.cacheWidth = data.cacheHeight = -1; | |
| 329 int currentWidth = Math.max (0, x2 - x1 - trim); | |
| 330 data.computeSize (child, currentWidth, data.height, flushCache); | |
| 331 if (flush is null) flush = new bool [children.length]; | |
| 332 flush [i] = true; | |
| 333 } | |
| 334 w = Math.max (x2, w); | |
| 335 if (move) { | |
| 336 if (bounds is null) bounds = new Rectangle [children.length]; | |
| 337 bounds [i] = new Rectangle (0, 0, 0, 0); | |
| 338 bounds [i].x = x + x1; | |
| 339 bounds [i].width = x2 - x1; | |
| 340 } | |
| 341 } else { | |
| 342 w = Math.max (computeWidth (child, data, flushCache), w); | |
| 343 } | |
| 344 } | |
| 345 for (int i=0; i<children.length; i++) { | |
| 346 Control child = children [i]; | |
| 347 FormData data = cast(FormData) child.getLayoutData (); | |
| 348 if (height !is SWT.DEFAULT) { | |
| 349 int y1 = data.getTopAttachment (child, spacing, flushCache).solveX (height); | |
| 350 int y2 = data.getBottomAttachment (child, spacing, flushCache).solveX (height); | |
| 351 h = Math.max (y2, h); | |
| 352 if (move) { | |
| 353 bounds [i].y = y + y1; | |
| 354 bounds [i].height = y2 - y1; | |
| 355 } | |
| 356 } else { | |
| 357 h = Math.max (computeHeight (child, data, flushCache), h); | |
| 358 } | |
| 359 } | |
| 360 for (int i=0; i<children.length; i++) { | |
| 361 Control child = children [i]; | |
| 362 FormData data = cast(FormData) child.getLayoutData (); | |
| 363 if (flush !is null && flush [i]) data.cacheWidth = data.cacheHeight = -1; | |
| 364 data.cacheLeft = data.cacheRight = data.cacheTop = data.cacheBottom = null; | |
| 365 } | |
| 366 if (move) { | |
| 367 for (int i=0; i<children.length; i++) { | |
| 368 children [i].setBounds (bounds [i]); | |
| 369 } | |
| 370 } | |
| 371 w += marginLeft + marginWidth * 2 + marginRight; | |
| 372 h += marginTop + marginHeight * 2 + marginBottom; | |
| 373 return new Point (w, h); | |
| 374 } | |
| 375 | |
| 376 /** | |
| 377 * Returns a string containing a concise, human-readable | |
| 378 * description of the receiver. | |
| 379 * | |
| 380 * @return a string representation of the layout | |
| 381 */ | |
| 382 override public String toString () { | |
| 383 String string = getName ()~" {"; | |
|
120
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
384 if (marginWidth !is 0) string ~= "marginWidth="~String_valueOf(marginWidth)~" "; |
|
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
385 if (marginHeight !is 0) string ~= "marginHeight="~String_valueOf(marginHeight)~" "; |
|
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
386 if (marginLeft !is 0) string ~= "marginLeft="~String_valueOf(marginLeft)~" "; |
|
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
387 if (marginRight !is 0) string ~= "marginRight="~String_valueOf(marginRight)~" "; |
|
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
388 if (marginTop !is 0) string ~= "marginTop="~String_valueOf(marginTop)~" "; |
|
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
389 if (marginBottom !is 0) string ~= "marginBottom="~String_valueOf(marginBottom)~" "; |
|
536e43f63c81
Comprehensive update for Win32/Linux32 dmd-2.053/dmd-1.068+Tango-r5661
Denis Shelomovskij <verylonglogin.reg@gmail.com>
parents:
51
diff
changeset
|
390 if (spacing !is 0) string ~= "spacing="~String_valueOf(spacing)~" "; |
| 25 | 391 string = string.trim(); |
| 392 string ~= "}"; | |
| 393 return string; | |
| 394 } | |
| 395 } |