Example: Structure Data

The following procedures build a simple application that displays the same structure data in two table widgets; one in row-major format and one in column-major format.

Example Code
This example is included in the file table_widget_example2.pro in the examples/doc/widgets subdirectory of the IDL distribution. Run this example procedure by entering table_widget_example2 at the IDL command prompt or view the file in an IDL Editor window by entering .EDIT table_widget_example2.pro. See Running the Example Code if IDL does not run the program as expected.

; Event-handler routine for 'Quit' button 
PRO table_widget_example2_quit_event, ev 
  WIDGET_CONTROL, ev.TOP, /DESTROY 
END 
 
; Widget creation routine. 
PRO table_widget_example2 
 
  ; Create some structure data. 
  d0={planet:'Mercury', orbit:0.387, radius:2439, moons:0} 
  d1={planet:'Venus', orbit:0.723, radius:6052, moons:0} 
  d2={planet:'Earth', orbit:1.0, radius:6378, moons:1} 
  d3={planet:'Mars', orbit:1.524, radius:3397, moons:2} 
 
  ; Combine structure data into a vector of structures. 
  data = [d0, d1, d2, d3] 
 
  ; Create labels for the rows or columns of the table. 
  labels = ['Planet', 'Orbit Radius (AU)', 'Radius (km)', 'Moons'] 
 
  ; To make sure the table looks nice on all platforms, 
  ; set all column widths to the width of the longest string 
  ; that can be a header. 
  max_strlen = strlen('Orbit Radius (AU)') 
  maxwidth = max_strlen * !d.x_ch_size + 6   ; ... + 6 for padding 
 
  ; Create base widget, two tables (column- and row-major, 
  ; respectively), and 'Quit' button. 
  base = WIDGET_BASE(/COLUMN) 
  table1 = WIDGET_TABLE(base, VALUE=data, /COLUMN_MAJOR, $ 
    ROW_LABELS=labels, COLUMN_LABELS='', $ 
    COLUMN_WIDTHS=maxwidth, /RESIZEABLE_COLUMNS) 
  table2 = WIDGET_TABLE(base, VALUE=data, /ROW_MAJOR, $ 
    ROW_LABELS='', COLUMN_LABELS=labels, /RESIZEABLE_COLUMNS) 
  b_quit = WIDGET_BUTTON(base, VALUE='Quit', $ 
    EVENT_PRO='table_widget_example2_quit_event') 
 
  ; Realize the widgets. 
  WIDGET_CONTROL, base, /REALIZE 
 
  ; Retrieve the widths of the columns of the first table. 
  ; Note that we must realize the widgets before retrieving 
  ; this value. 
  col_widths = WIDGET_INFO(table1, /COLUMN_WIDTHS) 
 
  ; We need the following trick to get the first column (which is 
  ; a header column in our first table) to reset to the width of 
  ; our data columns. The initial call to keyword COLUMN_WIDTHS 
  ; above only set the data column widths. 
  WIDGET_CONTROL, table1, COLUMN_WIDTHS=col_widths[0], $ 
    USE_TABLE_SELECT=[-1,-1,3,3] 
  ; This call gives table 2 the same cell dimensions as table 1 
  WIDGET_CONTROL, table2, COLUMN_WIDTHS=col_widths[0], $ 
    USE_TABLE_SELECT=[-1,-1,3,3] 
 
  ; Call XMANAGER to manage the widgets. 
  XMANAGER, 'table_widget_example2', base 
 
END

The following things about this example are worth noting: