MAN page from RedHat Other XITE-3.3-3.i386.rpm
Section: Free Widget Foundation (3)
Updated:
Index NAME
XfwfRowCol
DESCRIPTION
The RowCol widget forces all its children into rows and columns. Thechildren keep their preferred size, but the preferred position isignored. Resources determine how many rows or columns their should be(or as many as will fit) and if the children should be layed out inrows or in columns. In both methods, the children are placed on agrid, the size of which is determined by the width (height) of thewidest (tallest) child.
The children can be aligned in several ways: they can be placed in thecenter of their grid cell or against the edges. This is controlled bya resource of type Alignment.
Public variables
XfwfRowCol
| | Name | Class | Type | Default
| | XtNstoreByRow | XtCStoreByRow | Boolean | True
| | XtNrows | XtCRows | int | 0
| | XtNcolumns | XtCColumns | int | 0
| | XtNalignment | XtCAlignment | Alignment | XfwfTopLeft
| | XtNshrinkToFit | XtCShrinkToFit | Boolean | False
| | | |
|
|
- XtNstoreByRow
- The child widgets can be layed out in rows (left to right) or incolumns (top to bottom). The resource storeByRow can be True orFalse. True means children are added to the right of the previousone until the row is full, like words are added to a text. Falsemeans children are added below the previous one, until the column isfull.
Boolean storeByRow = True
- XtNrows
- The number of rows can be set with rows, or the number of columnscan be set with columns. If both are non-zero, rows will beignored. If rows is zero, there will be as many rows as needed. Ifcolumns is zero, there will be as many columns as needed. However,if both are zero, there will be as many columns as will fit in thecurrent width of the RowCol widget. By default, both rows andcolumns are zero.
int rows = 0
- XtNcolumns
int columns = 0
- XtNalignment
- The area of the RowCol widget is partitioned into rectangular cells(a grid). The cells are just large enough to contain the widest andthe tallest of the children. Within the cell, the children can be putin the top left corner (the default) or against one of the edges or inthe center. This is set with the alignment resource. The typeAlignment is defined in the ancestor class `Common'.
Alignment alignment = XfwfTopLeft
- XtNshrinkToFit
- The resource shrinkToFit determines how the size of the RowColwidget itself is computed. When it is False (default), thelocation resource is used to compute the widget's preferred size.When the value is True, the preferred size is computed fromthe totalwidth and height of the children. For example, when the widest childhas a width of w and columns > 0, the preferred width will becolumns * w + frame width. A similar computation is used for theheight. If columns > 0, only the height is computed this way. Ifcolumns = 0, rows > 0, only the width is computed.
Boolean shrinkToFit = False
- XtNframeType
- The inherited resource frameType is given a default value ofXfwfSunken, instead of the inherited default XfwfRaised. The framewidth is set to a default of 2 pixels, instead of 0.
frameType = XfwfSunken
- XtNframeWidth
frameWidth = 2
XfwfBoard
| | Name | Class | Type | Default
| | XtNabs_x | XtCAbs_x | Position | 0
| | XtNrel_x | XtCRel_x | Float | "0.0"
| | XtNabs_y | XtCAbs_y | Position | 0
| | XtNrel_y | XtCRel_y | Float | "0.0"
| | XtNabs_width | XtCAbs_width | Position | 0
| | XtNrel_width | XtCRel_width | Float | "1.0"
| | XtNabs_height | XtCAbs_height | Position | 0
| | XtNrel_height | XtCRel_height | Float | "1.0"
| | XtNhunit | XtCHunit | Float | "1.0"
| | XtNvunit | XtCVunit | Float | "1.0"
| | XtNlocation | XtCLocation | String | NULL
| | | |
|
|
XfwfFrame
| | Name | Class | Type | Default
| | XtNcursor | XtCCursor | Cursor | None
| | XtNframeType | XtCFrameType | FrameType | XfwfRaised
| | XtNframeWidth | XtCFrameWidth | Dimension | 0
| | XtNouterOffset | XtCOuterOffset | Dimension | 0
| | XtNinnerOffset | XtCInnerOffset | Dimension | 0
| | XtNshadowScheme | XtCShadowScheme | ShadowScheme | XfwfAuto
| | XtNtopShadowColor | XtCTopShadowColor | Pixel | compute_topcolor
| | XtNbottomShadowColor | XtCBottomShadowColor | Pixel | compute_bottomcolor
| | XtNtopShadowStipple | XtCTopShadowStipple | Bitmap | NULL
| | XtNbottomShadowStipple | XtCBottomShadowStipple | Bitmap | NULL
| | | |
|
|
XfwfCommon
| | Name | Class | Type | Default
| | XtNtraversalOn | XtCTraversalOn | Boolean | True
| | XtNhighlightThickness | XtCHighlightThickness | Dimension | 2
| | XtNhighlightColor | XtCHighlightColor | Pixel | XtDefaultForeground
| | XtNhighlightPixmap | XtCHighlightPixmap | Pixmap | None
| | XtNnextTop | XtCNextTop | Callback | NULL
| | XtNuserData | XtCUserData | Pointer | NULL
| | | |
|
|
Composite
| | Name | Class | Type | Default
| | XtNchildren | XtCChildren | WidgetList | NULL
| | insertPosition | XtCInsertPosition | XTOrderProc | NULL
| | numChildren | XtCNumChildren | Cardinal | 0
| | | |
|
|
Core
| | Name | Class | Type | Default
| | XtNx | XtCX | Position | 0
| | XtNy | XtCY | Position | 0
| | XtNwidth | XtCWidth | Dimension | 0
| | XtNheight | XtCHeight | Dimension | 0
| | borderWidth | XtCBorderWidth | Dimension | 0
| | XtNcolormap | XtCColormap | Colormap | NULL
| | XtNdepth | XtCDepth | Int | 0
| | destroyCallback | XtCDestroyCallback | XTCallbackList | NULL
| | XtNsensitive | XtCSensitive | Boolean | True
| | XtNtm | XtCTm | XTTMRec | NULL
| | ancestorSensitive | XtCAncestorSensitive | Boolean | False
| | accelerators | XtCAccelerators | XTTranslations | NULL
| | borderColor | XtCBorderColor | Pixel | 0
| | borderPixmap | XtCBorderPixmap | Pixmap | NULL
| | background | XtCBackground | Pixel | 0
| | backgroundPixmap | XtCBackgroundPixmap | Pixmap | NULL
| | mappedWhenManaged | XtCMappedWhenManaged | Boolean | True
| | XtNscreen | XtCScreen | Screen * | NULL
| | | |
|
|
Private variables
The width of the widest and the height of the tallest child are keptin private variables, for quicker access.
Dimension max_width
Dimension max_height
Methods
If a child becomes managed or unmanaged, the RowCol widgetrecomputes the positions of all managed children. That is done by amethod layout. In the process, the widget may ask its parent for adifferent size if shrinkToFit = True.
change_managed($){ $layout($, $shrinkToFit);}The layout function is responsible for moving the children to theirpositions in the grid. It is called from change_managed,geometry_manager and resize.
The function first computes the maximum width and height of all thechildren, including their borders. Then it computes the number of rowsand columns. All children are moved to their proper positions with thehelp of a utility function align_child, which aligns a child widgetto the grid.
If shrink = True, the RowCol widget also asks its parent for a newwidth and/or height, depending on the resulting layout.
layout($, int shrink){ int nrows, ncols, i, nchild, n; Position left, top, x, y; Dimension width, height, w, h; Widget child; nchild = 0; $max_width = 0; $max_height = 0; for (i = 0; i < $num_children; i++) { child = $children[i]; if (! XtIsManaged(child)) continue; nchild++; $max_width = max($max_width, $child$width + 2*$child$border_width); $max_height = max($max_height, $child$height + 2*$child$border_width); } $compute_inside($, left, top, width, height); if ($columns != 0) { ncols = $columns; nrows = (nchild + ncols - 1)/ncols; } else if ($rows != 0) { nrows = $rows; ncols = (nchild + nrows - 1)/nrows; } else { ncols = $max_width != 0 ? width/$max_width : 1; if (ncols == 0) ncols = 1; nrows = (nchild + ncols - 1)/ncols; } x = left; y = top; n = 0; if ($storeByRow) { for (i = 0; i < $num_children; i++) { child = $children[i]; if (! XtIsManaged(child)) continue; align_child(child, x, y, $max_width, $max_height, $alignment); n++; if (n == ncols) { n = 0; x = left; y += $max_height; } else x += $max_width; } } else { for (i = 0; i < $num_children; i++) { child = $children[i]; if (! XtIsManaged(child)) continue; align_child(child, x, y, $max_width, $max_height, $alignment); n++; if (n == nrows) { n = 0; y = top; x += $max_width; } else y += $max_height; } } if (shrink) { w = 2*left + ncols * $max_width; h = 2*top + nrows * $max_height; if ($columns != 0) XtVaSetValues($, XtNwidth, w, XtNheight, h, NULL); else XtVaSetValues($, XtNheight, h, NULL); }}When a child wants to change its size or border width, it calls itsparent's geometry_manager method (through a call toXtMakeGeometryRequest or XtMakeResizeRequest.) The RowCol widgetalways grants size changes to its children. The size change is carriedout immediately and a new layout is computed. If a child requests achange of position, the request is denied. A request for a change instacking order is ignored.
XtGeometryResult geometry_manager(Widget child, XtWidgetGeometry * request, XtWidgetGeometry * reply){ Dimension newwd, newht, newbd; if (request->request_mode (CWX | CWY)) return XtGeometryNo; if (request->request_mode XtCWQueryOnly) return XtGeometryYes; newwd = request->request_mode CWWidth ? request->width : $child$width; newht = request->request_mode CWHeight ? request->height : $child$height; newbd = request->request_mode CWBorderWidth ? request->border_width : $child$border_width; if (newwd == $child$width newht == $child$height newbd == $child$border_width) return XtGeometryNo; XtResizeWidget(child, newwd, newht, newbd); $layout($, $shrinkToFit); return XtGeometryDone;}The resize method is called when the widget is resized. If therows and columns resources are both zero, the children will haveto be be re-aligned. In this case, there is no sense in asking theparent for a new size, so layout is passed a value of False.
resize($){ if ($rows == 0 $columns == 0) $layout($, False);}The initialize method sets the private variables, in this case onlymax_width and max_height. There is no need to check if the resourceshave sensible values.
initialize(Widget request, $, ArgList args, Cardinal * num_args){ $max_width = $max_height = 0;}The RowCol widget needs to recompute the positions of the childrenwhen one of the resources changes. When the layout changes, the widgetalso needs to be redrawn, of course. The private variables are notdependent on the resources, so they don't need recomputing.
Boolean set_values(Widget old, Widget request, $, ArgList args, Cardinal * num_args){ Boolean need_layout = False; Boolean need_redisplay = False; if ($old$storeByRow != $storeByRow) need_layout = True; if ($old$rows != $rows) need_layout = True; if ($old$columns != $columns) need_layout = True; if ($old$alignment != $alignment) need_layout = True; if ($old$shrinkToFit != $shrinkToFit) need_layout = True; if (need_layout) { $layout($, $shrinkToFit); need_redisplay = True; } return need_redisplay;}
Utilities
char rcsid[] = "$Header: /local/blab/a/xite.Cvsroot/src/fwf/RowCol/XfwfRowCol.3,v 1.1 1997/03/23 14:46:42 svein Exp $"
align_child puts a widget in the proper position in the cell given bycx, cy, width and height.
align_child($, int cx, int cy, int width, int height, Alignment alignment){ Position x, y; if (alignment XfwfLeft) x = cx; else if (alignment XfwfRight) x = cx + width - $width; else x = cx + (width - $width) / 2; if (alignment XfwfTop) y = cy; else if (alignment XfwfBottom) y = cy + height - $height; else y = cy + (height - $height) / 2; XtMoveWidget($, x, y);}
Index
- NAME
- DESCRIPTION
- Public variables
- Private variables
- Methods
- Utilities
This document was created byman2html,using the manual pages.
