wid — The preview widget ID.wid — The preview widget ID.object — A string containing the type of area to be committed. Valid areas are: 'HEADER', 'RECORD', 'FIELD'.status — Indicates whether WtPreview has already flagged an error. If status is nonzero, an error detection has occurred. For example, if the area selected by the user is invalid, status is nonzero.area — A four-element vector specifying the exact lines and columns of the preview window to commit. This vector specifies the following positions: the starting line, starting column, ending line, and ending column.doit — An output parameter that gives the go-ahead to commit the selection. A value of 0 indicates that the selection should be refused; a nonzero value means the selection is accepted.wid — The preview widget ID.object — The type of area — 'HEADER', 'RECORD', or 'FIELD' — to be cleared.area — A four-element vector specifying the exact lines and columns of the preview window to clear. This vector specifies the following positions: the starting line, starting column, ending line, and ending column.Header — One or more lines at the beginning of the data file that are ignored because they do not contain meaningful data.Record — The smallest portion of the file that contains a set of data (one value from each field). A record can be defined to be exactly one line, less than one line, or more than one line of the data file. A record must start in the first column of the data file and must be on the line immediately following the header.Field — A specific area in the file that contains a value and is contained in the record.StartSelection — Marks the beginning of the specific area. By default, a selection is started when the user clicks MB1.EndSelection — Marks the end of the specific area. By default, a selection is ended when the user clicks MB2.ConfirmSelection — Confirms the current selection. By default, a selection is confirmed when the user clicks MB3.note | The application in this example uses the PV‑WAVE Widgets function WwPreviewUtils to provide some additional functionality not available with WwPreview, such as clearing previously defined areas and setting characters used for filtering and data separation. |
 |
PRO ConfirmSelected, wid, object, status, area, doit
PRINT, 'object confirmed:', object, 'status:', status
PRINT, 'area:', area
PRINT, 'doit:', doit
END
PRO ClearSelected, wid, object, area
PRINT, 'object cleared:', object
PRINT, 'area:', area
END
PRO FileOK, wid, fsshell
COMMON PREVIEW_Widgets, top, shell, preview
filename = WwGetValue(wid)
OPENR, /Get_Lun, unit, filename
source = ''
line = ''
WHILE NOT eof(unit) DO BEGIN
READF, unit, line
source = source + line + '\012'
ENDWHILE
FREE_LUN, unit
status = WwSetValue(preview, source)
status = WwSetValue(fsshell, /Close)
END
PRO FileDone, wid, fsshell
status = WwSetValue(fsshell, /Close)
END
PRO FileMenuCB, wid, index
@wtxmconsts
COMMON PREVIEW_Widgets, top, shell, preview
CASE index OF
1: BEGIN
file = WwFileSelection(wid, 'FileOK', 'FileDone', $
TITLE='Search', Dir=!Dir+'/data/')
END
2: BEGIN
status = WwSetValue(top, /Close)
END
ENDCASE
END
PRO EditMenuCB, wid, index
COMMON PREVIEW_Widgets, top, shell, preview
@wtxmconsts
CASE index OF
1: BEGIN
status = WwPreviewUtils(preview, /Clear, /All)
END
2: BEGIN
status = WwPreviewUtils(preview, 'RECORD', $
1, [0, 54, 3, 3], /Clear)
END
3: BEGIN
header = [0,53,0,2]
status = WwPreviewUtils(preview, 'HEADER',1,$
header, /Commit)
record = [0,54,3,3]
status = WwPreviewUtils(preview, 'RECORD', $
record, /Commit)
END
ENDCASE
END
PRO SeparatorsOK, wid, index
COMMON PREVIEW_Widgets, top, shell, preview
status = WtSet(preview, {, $separatorChars:WwGetValue(wid)})
END
PRO FiltersOK, wid, index
COMMON PREVIEW_Widgets, top, shell, preview
status = WtSet(preview, {, filterChars:WwGetValue(wid)})END
PRO OptionsMenuCB, wid, index
COMMON PREVIEW_Widgets, top, shell, preview
CASE index OF
2: BEGIN
separ = WtGet(preview, 'separatorChars')
status = WwDialog(preview, 'Separators:', $
'SeparatorsOK', Text=separ)
END
3: BEGIN
filter = WtGet(preview, 'filterChars')
status = WwDialog(preview, 'Filters:',$
'FiltersOK', Text = filter)
END
ENDCASE
END
PRO FormatMenuCB, wid, index
@wtxmconsts
COMMON PREVIEW_Widgets, top, shell, preview
CASE index OF
1: BEGIN
status = WtSet(preview, {, $formatType:XmFORMAT_FIXED})
END
2: BEGIN
status = WtSet(preview, {, $formatType:XmFORMAT_FREE})
END
ENDCASE
END
PRO ButtonCB, wid, data
@wtxmconsts
COMMON PREVIEW_Widgets, top, shell, preview
CASE data OF
1: BEGIN
status = WwPreviewUtils(preview, /AutoDefine)
END
2: BEGIN
status = WtSet(preview, {, $selectionMode:XmHEADER_PW_OBJECT})
END
3: BEGIN
status = WtSet(preview, {, $selectionMode:XmRECORD_PW_OBJECT})
END
4: BEGIN
status = WtSet(preview, {, $selectionMode:XmFIELD_PW_OBJECT})
END
5: BEGIN
status = WtSet(preview, {, $selectionMode:XmANY_PW_OBJECT})
END
ENDCASE
END
PRO wwpreview_ex1
@wtxmclasses
@wtxmconsts
COMMON PREVIEW_Widgets, top, shell, preview
top = WwInit('preview', 'Preview', layout, $Title='Preview', Background='White', $
Foreground='red', $
/Form, Border=3, Position=[100, 100])
menus = {, menubutton:'File', $ menu:{, callback:'FileMenuCB', $button:'Open', button:'Quit'}, $
menubutton:'Edit', menu:{, callback:'EditMenuCB', $button:'Clear All', button:'Clear', $
button:'Set areas'}, menubutton:'Options', $
menu:{, callback:'OptionsMenuCB', $ menubutton:'Format', menu:{, callback:'FormatMenuCB', $button:'Fixed', button:'Free'}, $
button:'Separators...', button:'Filter...'} $
}
bar = WwMenuBar(layout, menus, /Left, /Right, /Top, $
Font = '-adobe-times-bold-r-normal--14*')
preview = WwPreview(layout, 'ConfirmSelected', $
'ClearSelected', /Auto, File=!data_dir + 'air_qual.dat', $
Top = bar, /Left, /Right, $
Visible = [20, 60], Font = font, $
Foreground = 'Blue', Background = 'LightGrey')
labels = ['Auto Define', 'Header', 'Record', $
'Fields', 'Any']
bbox = WwButtonBox(layout, labels, 'ButtonCB', $
/Horizontal, Spacing=5, $
Top=preview, /Left, /Right, /Bottom)
status = WwSetValue(top, /Display)
WwLoop
END