/ lib / tcltk / tk8.6 / demos / items.tcl
items.tcl
  1  # items.tcl --
  2  #
  3  # This demonstration script creates a canvas that displays the
  4  # canvas item types.
  5  
  6  if {![info exists widgetDemo]} {
  7      error "This script should be run from the \"widget\" demo."
  8  }
  9  
 10  package require Tk
 11  
 12  set w .items
 13  catch {destroy $w}
 14  toplevel $w
 15  wm title $w "Canvas Item Demonstration"
 16  wm iconname $w "Items"
 17  positionWindow $w
 18  set c $w.frame.c
 19  
 20  label $w.msg -font $font -wraplength 5i -justify left -text "This window contains a canvas widget with examples of the various kinds of items supported by canvases.  The following operations are supported:\n  Left-Button drag:\tmoves item under pointer.\n  Middle-Button drag:\trepositions view.\n  Right-Button drag:\tstrokes out area.\n  Ctrl+f:\t\tprints items under area."
 21  pack $w.msg -side top
 22  
 23  ## See Code / Dismiss buttons
 24  set btns [addSeeDismiss $w.buttons $w]
 25  pack $btns -side bottom -fill x
 26  
 27  frame $w.frame
 28  pack $w.frame -side top -fill both -expand yes
 29  
 30  canvas $c -scrollregion {0c 0c 30c 24c} -width 15c -height 10c \
 31  	-relief sunken -borderwidth 2 \
 32  	-xscrollcommand "$w.frame.hscroll set" \
 33  	-yscrollcommand "$w.frame.vscroll set"
 34  ttk::scrollbar $w.frame.vscroll -command "$c yview"
 35  ttk::scrollbar $w.frame.hscroll -orient horiz -command "$c xview"
 36  
 37  grid $c -in $w.frame \
 38      -row 0 -column 0 -rowspan 1 -columnspan 1 -sticky news
 39  grid $w.frame.vscroll \
 40      -row 0 -column 1 -rowspan 1 -columnspan 1 -sticky news
 41  grid $w.frame.hscroll \
 42      -row 1 -column 0 -rowspan 1 -columnspan 1 -sticky news
 43  grid rowconfig    $w.frame 0 -weight 1 -minsize 0
 44  grid columnconfig $w.frame 0 -weight 1 -minsize 0
 45  
 46  # Display a 3x3 rectangular grid.
 47  
 48  $c create rect 0c 0c 30c 24c -width 2
 49  $c create line 0c 8c 30c 8c -width 2
 50  $c create line 0c 16c 30c 16c -width 2
 51  $c create line 10c 0c 10c 24c -width 2
 52  $c create line 20c 0c 20c 24c -width 2
 53  
 54  set font1 {Helvetica 12}
 55  set font2 {Helvetica 24 bold}
 56  if {[winfo depth $c] > 1} {
 57      set blue DeepSkyBlue3
 58      set red red
 59      set bisque bisque3
 60      set green SeaGreen3
 61  } else {
 62      set blue black
 63      set red black
 64      set bisque black
 65      set green black
 66  }
 67  
 68  # Set up demos within each of the areas of the grid.
 69  
 70  $c create text 5c .2c -text Lines -anchor n
 71  $c create line 1c 1c 3c 1c 1c 4c 3c 4c -width 2m -fill $blue \
 72  	-cap butt -join miter -tags item
 73  $c create line 4.67c 1c 4.67c 4c -arrow last -tags item
 74  $c create line 6.33c 1c 6.33c 4c -arrow both -tags item
 75  $c create line 5c 6c 9c 6c 9c 1c 8c 1c 8c 4.8c 8.8c 4.8c 8.8c 1.2c \
 76  	8.2c 1.2c 8.2c 4.6c 8.6c 4.6c 8.6c 1.4c 8.4c 1.4c 8.4c 4.4c \
 77  	-width 3 -fill $red -tags item
 78  # Main widget program sets variable tk_demoDirectory
 79  $c create line 1c 5c 7c 5c 7c 7c 9c 7c -width .5c \
 80  	-stipple @[file join $tk_demoDirectory images gray25.xbm] \
 81  	-arrow both -arrowshape {15 15 7} -tags item
 82  $c create line 1c 7c 1.75c 5.8c 2.5c 7c 3.25c 5.8c 4c 7c -width .5c \
 83  	-cap round -join round -tags item
 84  
 85  $c create text 15c .2c -text "Curves (smoothed lines)" -anchor n
 86  $c create line 11c 4c 11.5c 1c 13.5c 1c 14c 4c -smooth on \
 87  	-fill $blue -tags item
 88  $c create line 15.5c 1c 19.5c 1.5c 15.5c 4.5c 19.5c 4c -smooth on \
 89  	-arrow both -width 3 -tags item
 90  $c create line 12c 6c 13.5c 4.5c 16.5c 7.5c 18c 6c \
 91  	16.5c 4.5c 13.5c 7.5c 12c 6c -smooth on -width 3m -cap round \
 92  	-stipple @[file join $tk_demoDirectory images gray25.xbm] \
 93  	-fill $red -tags item
 94  
 95  $c create text 25c .2c -text Polygons -anchor n
 96  $c create polygon 21c 1.0c 22.5c 1.75c 24c 1.0c 23.25c 2.5c \
 97  	24c 4.0c 22.5c 3.25c 21c 4.0c 21.75c 2.5c -fill $green \
 98  	-outline {} -width 4 -tags item
 99  $c create polygon 25c 4c 25c 4c 25c 1c 26c 1c 27c 4c 28c 1c \
100  	29c 1c 29c 4c 29c 4c -fill $red -outline {} -smooth on -tags item
101  $c create polygon 22c 4.5c 25c 4.5c 25c 6.75c 28c 6.75c \
102  	28c 5.25c 24c 5.25c 24c 6.0c 26c 6c 26c 7.5c 22c 7.5c \
103  	-stipple @[file join $tk_demoDirectory images gray25.xbm] \
104  	-fill $blue -outline {} -tags item
105  
106  $c create text 5c 8.2c -text Rectangles -anchor n
107  $c create rectangle 1c 9.5c 4c 12.5c -outline $red -width 3m -tags item
108  $c create rectangle 0.5c 13.5c 4.5c 15.5c -fill $green -tags item
109  $c create rectangle 6c 10c 9c 15c -outline {} \
110  	-stipple @[file join $tk_demoDirectory images gray25.xbm] \
111  	-fill $blue -tags item
112  
113  $c create text 15c 8.2c -text Ovals -anchor n
114  $c create oval 11c 9.5c 14c 12.5c -outline $red -width 3m -tags item
115  $c create oval 10.5c 13.5c 14.5c 15.5c -fill $green -tags item
116  $c create oval 16c 10c 19c 15c -outline {} \
117  	-stipple @[file join $tk_demoDirectory images gray25.xbm] \
118  	-fill $blue -tags item
119  
120  $c create text 25c 8.2c -text Text -anchor n
121  $c create rectangle 22.4c 8.9c 22.6c 9.1c
122  $c create text 22.5c 9c -anchor n -font $font1 -width 4c \
123  	-text "A short string of text, word-wrapped, justified left, and anchored north (at the top).  The rectangles show the anchor points for each piece of text." -tags item
124  $c create rectangle 25.4c 10.9c 25.6c 11.1c
125  $c create text 25.5c 11c -anchor w -font $font1 -fill $blue \
126  	-text "Several lines,\n each centered\nindividually,\nand all anchored\nat the left edge." \
127  	-justify center -tags item
128  $c create rectangle 24.9c 13.9c 25.1c 14.1c
129  catch {
130  $c create text 25c 14c -font $font2 -anchor c -fill $red -angle 15 \
131  	-text "Angled characters" -tags item
132  }
133  
134  $c create text 5c 16.2c -text Arcs -anchor n
135  $c create arc 0.5c 17c 7c 20c -fill $green -outline black \
136  	-start 45 -extent 270 -style pieslice -tags item
137  $c create arc 6.5c 17c 9.5c 20c -width 4m -style arc \
138  	-outline $blue -start -135 -extent 270 -tags item \
139  	-outlinestipple @[file join $tk_demoDirectory images gray25.xbm]
140  $c create arc 0.5c 20c 9.5c 24c -width 4m -style pieslice \
141  	-fill {} -outline $red -start 225 -extent -90 -tags item
142  $c create arc 5.5c 20.5c 9.5c 23.5c -width 4m -style chord \
143  	-fill $blue -outline {} -start 45 -extent 270  -tags item
144  
145  $c create text 15c 16.2c -text "Bitmaps and Images" -anchor n
146  catch {
147  image create photo items.ousterhout \
148      -file [file join $tk_demoDirectory images ouster.png]
149  image create photo items.ousterhout.active -format "png -alpha 0.5" \
150      -file [file join $tk_demoDirectory images ouster.png]
151  $c create image 13c 20c -tags item -image items.ousterhout \
152      -activeimage items.ousterhout.active
153  }
154  $c create bitmap 17c 18.5c -tags item \
155  	-bitmap @[file join $tk_demoDirectory images noletter.xbm]
156  $c create bitmap 17c 21.5c -tags item \
157  	-bitmap @[file join $tk_demoDirectory images letters.xbm]
158  
159  $c create text 25c 16.2c -text Windows -anchor n
160  button $c.button -text "Press Me" -command "butPress $c $red"
161  $c create window 21c 18c -window $c.button -anchor nw -tags item
162  entry $c.entry -width 20 -relief sunken
163  $c.entry insert end "Edit this text"
164  $c create window 21c 21c -window $c.entry -anchor nw -tags item
165  scale $c.scale -from 0 -to 100 -length 6c -sliderlength .4c \
166  	-width .5c -tickinterval 0
167  $c create window 28.5c 17.5c -window $c.scale -anchor n -tags item
168  $c create text 21c 17.9c -text Button: -anchor sw
169  $c create text 21c 20.9c -text Entry: -anchor sw
170  $c create text 28.5c 17.4c -text Scale: -anchor s
171  
172  # Set up event bindings for canvas:
173  
174  $c bind item <Enter> "itemEnter $c"
175  $c bind item <Leave> "itemLeave $c"
176  if {[tk windowingsystem] eq "aqua" && ![package vsatisfies [package provide Tk] 8.7-]} {
177      bind $c <Button-2> "itemMark $c %x %y"
178      bind $c <B2-Motion> "itemStroke $c %x %y"
179      bind $c <Button-3> "$c scan mark %x %y"
180      bind $c <B3-Motion> "$c scan dragto %x %y"
181  } else {
182      bind $c <Button-2> "$c scan mark %x %y"
183      bind $c <B2-Motion> "$c scan dragto %x %y"
184      bind $c <Button-3> "itemMark $c %x %y"
185      bind $c <B3-Motion> "itemStroke $c %x %y"
186  }
187  bind $c <<NextChar>> "itemsUnderArea $c"
188  bind $c <Button-1> "itemStartDrag $c %x %y"
189  bind $c <B1-Motion> "itemDrag $c %x %y"
190  
191  # Utility procedures for highlighting the item under the pointer:
192  
193  proc itemEnter {c} {
194      global restoreCmd
195  
196      if {[winfo depth $c] == 1} {
197  	set restoreCmd {}
198  	return
199      }
200      set type [$c type current]
201      if {$type == "window" || $type == "image"} {
202  	set restoreCmd {}
203  	return
204      } elseif {$type == "bitmap"} {
205  	set bg [lindex [$c itemconf current -background] 4]
206  	set restoreCmd [list $c itemconfig current -background $bg]
207  	$c itemconfig current -background SteelBlue2
208  	return
209      } elseif {$type == "image"} {
210  	set restoreCmd [list $c itemconfig current -state normal]
211  	$c itemconfig current -state active
212  	return
213      }
214      set fill [lindex [$c itemconfig current -fill] 4]
215      if {(($type == "rectangle") || ($type == "oval") || ($type == "arc"))
216  	    && ($fill == "")} {
217  	set outline [lindex [$c itemconfig current -outline] 4]
218  	set restoreCmd "$c itemconfig current -outline $outline"
219  	$c itemconfig current -outline SteelBlue2
220      } else {
221  	set restoreCmd "$c itemconfig current -fill $fill"
222  	$c itemconfig current -fill SteelBlue2
223      }
224  }
225  
226  proc itemLeave {c} {
227      global restoreCmd
228  
229      eval $restoreCmd
230  }
231  
232  # Utility procedures for stroking out a rectangle and printing what's
233  # underneath the rectangle's area.
234  
235  proc itemMark {c x y} {
236      global areaX1 areaY1
237      set areaX1 [$c canvasx $x]
238      set areaY1 [$c canvasy $y]
239      $c delete area
240  }
241  
242  proc itemStroke {c x y} {
243      global areaX1 areaY1 areaX2 areaY2
244      set x [$c canvasx $x]
245      set y [$c canvasy $y]
246      if {($areaX1 != $x) && ($areaY1 != $y)} {
247  	$c delete area
248  	$c addtag area withtag [$c create rect $areaX1 $areaY1 $x $y \
249  		-outline black]
250  	set areaX2 $x
251  	set areaY2 $y
252      }
253  }
254  
255  proc itemsUnderArea {c} {
256      global areaX1 areaY1 areaX2 areaY2
257      set area [$c find withtag area]
258      set items ""
259      foreach i [$c find enclosed $areaX1 $areaY1 $areaX2 $areaY2] {
260  	if {[lsearch [$c gettags $i] item] >= 0} {
261  	    lappend items $i
262  	}
263      }
264      puts stdout "Items enclosed by area: $items"
265      set items ""
266      foreach i [$c find overlapping $areaX1 $areaY1 $areaX2 $areaY2] {
267  	if {[lsearch [$c gettags $i] item] >= 0} {
268  	    lappend items $i
269  	}
270      }
271      puts stdout "Items overlapping area: $items"
272  }
273  
274  set areaX1 0
275  set areaY1 0
276  set areaX2 0
277  set areaY2 0
278  
279  # Utility procedures to support dragging of items.
280  
281  proc itemStartDrag {c x y} {
282      global lastX lastY
283      set lastX [$c canvasx $x]
284      set lastY [$c canvasy $y]
285  }
286  
287  proc itemDrag {c x y} {
288      global lastX lastY
289      set x [$c canvasx $x]
290      set y [$c canvasy $y]
291      $c move current [expr {$x-$lastX}] [expr {$y-$lastY}]
292      set lastX $x
293      set lastY $y
294  }
295  
296  # Procedure that's invoked when the button embedded in the canvas
297  # is invoked.
298  
299  proc butPress {w color} {
300      set i [$w create text 25c 18.1c -text "Oooohhh!!" -fill $color -anchor n]
301      after 500 "$w delete $i"
302  }