# Utility procedures for highlighting the item under the pointer:
sub itemEnter {
my($c) = @_;
$mkItems::restoreCmd = '';
if ($mkItems->depth == 1) {
$mkItems::restoreCmd = '';
return;
}
my $type = $c->type('current');
if ($type eq 'window') {
$mkItems::restoreCmd = '';
return;
}
if ($type eq 'bitmap') {
my $bg = ($c->itemconfigure('current', -background))[4];
if (defined $bg) {
$mkItems::restoreCmd = "\$c->itemconfigure('current', -background => '$bg');";
} else {
$mkItems::restoreCmd = "\$c->itemconfigure('current', -background => undef);";
}
$c->itemconfigure('current', -background => 'SteelBlue2');
return;
}
my $fill = ($c->itemconfigure('current', -fill))[4];
if (($type eq 'rectangle' or $type eq 'oval' or $type eq 'arc') and not defined $fill) {
my $outline = ($c->itemconfigure('current', -outline))[4];
$mkItems::restoreCmd = "\$c->itemconfigure('current', -outline => '$outline')";
$c->itemconfigure('current', -outline => 'SteelBlue2');
} else {
$mkItems::restoreCmd = "\$c->itemconfigure('current', -fill => '$fill')";
$c->itemconfigure('current', -fill => 'SteelBlue2');
}
} # end itemEnter
sub itemLeave {
local ($c) = @_;
eval $mkItems::restoreCmd;
} # end itemLeave
# Utility procedures to support dragging of items.
sub itemStartDrag {
my($c, $x, $y) = @_;
$mkItems::lastX = $c->canvasx($x);
$mkItems::lastY = $c->canvasy($y);
} # end itemStartDrag
sub itemDrag {
my($c, $x, $y) = @_;
$x = $c->canvasx($x);
$y = $c->canvasy($y);
$c->move('current', $x-$mkItems::lastX, $y-$mkItems::lastY);
$mkItems::lastX = $x;
$mkItems::lastY = $y;
} # end itemDrag
# Utility procedures for stroking out a rectangle and printing what's underneath the rectangle's area.
$mkItems::areaX1 = 0;
$mkItems::areaY1 = 0;
$mkItems::areaX2 = 0;
$mkItems::areaY2 = 0;
sub itemMark {
my($c, $x, $y) = @_;
$mkItems::areaX1 = $c->canvasx($x);
$mkItems::areaY1 = $c->canvasy($y);
$c->delete('area');
} # end itemMark
sub itemStroke {
my($c, $x, $y) = @_;
$x = $c->canvasx($x);
$y = $c->canvasy($y);
if (($mkItems::areaX1 != $x) and ($mkItems::areaY1 != $y)) {
$c->delete('area');
$c->addtag('area', 'withtag', $c->create('rectangle', $mkItems::areaX1, $mkItems::areaY1, $x, $y, -outline => 'black'));
$mkItems::areaX2 = $x;
$mkItems::areaY2 = $y;
}
} # end itemStroke
sub itemsUnderArea {
my($c) = @_;
my $area = $c->find('withtag', 'area');
my @items = ();
my $i;
foreach $i ($c->find('enclosed', $mkItems::areaX1, $mkItems::areaY1, $mkItems::areaX2, $mkItems::areaY2)) {
my @tags = $c->gettags($i);
if (defined($tags[0]) and grep $_ eq 'item', @tags) {
push @items, $i;
}
}
@items = 'None' unless @items;
print STDOUT 'Items enclosed by area: ', join(' ', @items), ".\n";
@items = ();
foreach $i ($c->find('overlapping', $mkItems::areaX1, $mkItems::areaY1, $mkItems::areaX2, $mkItems::areaY2)) {
my @tags = $c->gettags($i);
if (defined($tags[0]) and grep $_ eq 'item', @tags) {
push @items, $i;
}
}
@items = 'None' unless @items;
print STDOUT 'Items overlapping area: ', join(' ', @items), ".\n";
} # end itemsUnderArea
sub butPress {
# Procedure that's invoked when the button embedded in the canvas is invoked.
my($w, $color) = @_;
my $i = $w->create(qw(text 25c 18.1c -anchor n), -text => 'Ouch!!', -fill => $color);
$w->after(500, sub { $w->delete($i) });
} # end butPress
sub mkItems {
# Create a top-level window containing a canvas that displays the various item types and allows them to be selected and
# moved. This demo can be used to test out the point-hit and rectangle-hit code for items.
$mkItems->destroy if Exists($mkItems);
$mkItems = $top->Toplevel();
my $w = $mkItems;
dpos $w;
$w->title('Canvas Item Demonstration');
$w->iconname('Items');
$w->minsize(100, 100);
my $w_msg = $w->Label(-font => '-Adobe-Times-Medium-R-Normal--*-180-*-*-*-*-*-*', -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 Button-1 " .
"drag:\tmoves item under pointer.\n Button-2 drag:\trepositions view.\n Button-3 drag:\t" .
"strokes out area.\n Ctrl+f:\t\tdisplays items under area.");
my $w_frame2 = $w->Frame();
my $w_ok = $w->Button(-text => 'OK', -width => 8, -command => ['destroy', $w]);
$w_msg->pack(-side => 'top', -fill => 'x');
$w_frame2->pack(-side => 'top', -fill => 'both', -expand => 'yes');
$w_ok->pack(-side => 'bottom', -pady => '5', -anchor => 'center');
my $c = $w_frame2->Canvas(-scrollregion => ['0c', '0c', '30c', '24c'], -width => '15c', -height => '10c',
-relief => 'sunken', -bd => 2);
my $w_frame2_vscroll = $w_frame2->Scrollbar(-command => ['yview', $c]);
my $w_frame2_hscroll = $w_frame2->Scrollbar(-orient => 'horiz', -command => ['xview', $c]);
$c->configure(-xscrollcommand => ['set', $w_frame2_hscroll]);
$c->configure(-yscrollcommand => ['set', $w_frame2_vscroll]);
$w_frame2_hscroll->pack(-side => 'bottom', -fill => 'x');
$w_frame2_vscroll->pack(-side => 'right', -fill => 'y');
$c->pack(-expand => 'yes', -fill => 'both');
# Display a 3x3 rectangular grid.
$c->create(qw(rect 0c 0c 30c 24c -width 2));
$c->create(qw(line 0c 8c 30c 8c -width 2));
$c->create(qw(line 0c 16c 30c 16c -width 2));
$c->create(qw(line 10c 0c 10c 24c -width 2));
$c->create(qw(line 20c 0c 20c 24c -width 2));
$font1 = '-Adobe-Helvetica-Medium-R-Normal--*-120-*-*-*-*-*-*';
$font2 = '-Adobe-Helvetica-Bold-R-Normal--*-240-*-*-*-*-*-*';
if ($mkItems->depth > 1) {
$blue = 'DeepSkyBlue3';
$red = 'red';
$bisque = 'bisque3';
$green = 'SeaGreen3';
} else {
$blue = 'black';
$red = 'black';
$bisque = 'black';
$green = 'black';
}
# Set up demos within each of the areas of the grid.
$c->create(qw(text 5c .2c -text Lines -anchor n));
$c->create(qw(line 1c 1c 3c 1c 1c 4c 3c 4c -width 2m), -fill => $blue, qw(-cap butt -join miter -tags item));
$c->create(qw(line 4.67c 1c 4.67c 4c -arrow last -tags item));
$c->create(qw(line 6.33c 1c 6.33c 4c -arrow both -tags item));
$c->create(qw(line 5c 6c 9c 6c 9c 1c 8c 1c 8c 4.8c 8.8c 4.8c 8.8c 1.2c 8.2c 1.2c 8.2c 4.6c 8.6c 4.6c 8.6c 1.4c 8.4c 1.4c
8.4c 4.4c -width 3), -fill => $red, qw(-tags item));
$c->create(qw(line 1c 5c 7c 5c 7c 7c 9c 7c -width .5c), -stipple => '@'.Tk->findINC('demos/images/grey.25'),
qw(-arrow both), -arrowshape => [15, 15, 7], qw(-tags item));
$c->create(qw(line 1c 7c 1.75c 5.8c 2.5c 7c 3.25c 5.8c 4c 7c -width .5c -cap round -join round -tags item));
$c->create(qw(text 15c .2c), -text => 'Curves (smoothed lines)', qw(-anchor n));
$c->create(qw(line 11c 4c 11.5c 1c 13.5c 1c 14c 4c -smooth on), -fill =>$blue, qw(-tags item));
$c->create(qw(line 15.5c 1c 19.5c 1.5c 15.5c 4.5c 19.5c 4c -smooth on -arrow both -width 3 -tags item));
$c->create(qw(line 12c 6c 13.5c 4.5c 16.5c 7.5c 18c 6c 16.5c 4.5c 13.5c 7.5c 12c 6c -smooth on -width 3m -cap round),
-stipple => '@'.Tk->findINC('demos/images/grey.25'), -fill => $red, qw(-tags item));
$c->create(qw(text 25c .2c -text Polygons -anchor n));
$c->create(qw(polygon 21c 1.0c 22.5c 1.75c 24c 1.0c 23.25c 2.5c 24c 4.0c 22.5c 3.25c 21c 4.0c 21.75c 2.5c),
-fill => $green, qw( -tags item));
$c->create(qw(polygon 25c 4c 25c 4c 25c 1c 26c 1c 27c 4c 28c 1c 29c 1c 29c 4c 29c 4c), -fill => $red,
qw(-smooth on -tags item));
$c->create(qw(polygon 22c 4.5c 25c 4.5c 25c 6.75c 28c 6.75c 28c 5.25c 24c 5.25c 24c 6.0c 26c 6c 26c 7.5c 22c 7.5c),
-stipple => '@'.Tk->findINC('demos/images/grey.25'), qw( -tags item));
$c->create(qw(text 5c 8.2c -text Rectangles -anchor n));
$c->create(qw(rectangle 1c 9.5c 4c 12.5c), -outline => $red, qw(-width 3m -tags item));
$c->create(qw(rectangle 0.5c 13.5c 4.5c 15.5c), -fill => $green, qw(-tags item));
$c->create(qw(rectangle 6c 10c 9c 15c), -outline => undef, -stipple => '@'.Tk->findINC('demos/images/grey.25'), -fill => $blue,
qw(-tags item));
$c->create(qw(text 15c 8.2c -text Ovals -anchor n));
$c->create(qw(oval 11c 9.5c 14c 12.5c), -outline => $red, qw(-width 3m -tags item));
$c->create(qw(oval 10.5c 13.5c 14.5c 15.5c), -fill => $green, qw(-tags item));
$c->create(qw(oval 16c 10c 19c 15c), -outline => undef, -stipple => '@'.Tk->findINC('demos/images/grey.25'), -fill => $blue,
qw(-tags item));
$c->create(qw(text 25c 8.2c -text Text -anchor n));
$c->create(qw(rectangle 22.4c 8.9c 22.6c 9.1c));
$c->create(qw(text 22.5c 9c -anchor n -width 4c), -font => $font1, -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.', qw(-tags item));
$c->create(qw(rectangle 25.4c 10.9c 25.6c 11.1c));
$c->create(qw(text 25.5c 11c -anchor w), -font => $font1, -fill => $blue, -text => "Several lines,\n each centered\n" .
"individually,\nand all anchored\nat the left edge.", qw(-justify center -tags item));
$c->create(qw(rectangle 24.9c 13.9c 25.1c 14.1c));
$c->create(qw(text 25c 14c -anchor c), -font => $font2, -fill => $red, -stipple => '@'.Tk->findINC('demos/images/grey.5'),
-text => 'Stippled characters', qw(-tags item));
$c->create(qw(text 5c 16.2c -text Arcs -anchor n));
$c->create(qw(arc 0.5c 17c 7c 20c), -fill => $green, qw(-outline black -start 45 -extent 270 -style pieslice -tags item));
$c->create(qw(arc 6.5c 17c 9.5c 20c -width 4m -style arc), -fill => $blue, -stipple => '@'.Tk->findINC('demos/images/grey.25'),
qw(-start -135 -extent 270 -tags item));
$c->create(qw(arc 0.5c 20c 9.5c 24c -width 4m -style pieslice), -fill => undef, -outline => $red,
qw(-start 225 -extent -90 -tags item));
$c->create(qw(arc 5.5c 20.5c 9.5c 23.5c -width 4m -style chord), -fill => $blue, -outline => undef,
qw(-start 45 -extent 270 -tags item));
$c->create(qw(text 15c 16.2c -text Bitmaps -anchor n));
$c->create(qw(bitmap 13c 20c), -bitmap => '@'.Tk->findINC('demos/images/face'), qw(-tags item));
$c->create(qw(bitmap 17c 18.5c), -bitmap => '@'.Tk->findINC('demos/images/noletters'), qw(-tags item));
$c->create(qw(bitmap 17c 21.5c), -bitmap => '@'.Tk->findINC('demos/images/letters'), qw(-tags item));
$c->create(qw(text 25c 16.2c -text Windows -anchor n));
my $c_button = $c->Button(-text => 'Press Me', -command => [sub {butPress(@_)}, $c, $red]);
$c->create(qw(window 21c 18c), -window => $c_button, qw(-anchor nw -tags item));
my $c_entry = $c->Entry(-width => '20', -relief => 'sunken');
$c_entry->insert('end' => 'Edit this text');
$c->create(qw(window 21c 21c), -window => $c_entry, qw(-anchor nw -tags item));
my $c_scale = $c->Scale(-from => '0', -to => '100', '-length' => '6c', -sliderlength => '.4c', -width => '.5c',
-tickinterval => '0');
$c->create(qw(window 28.5c 17.5c), -window => $c_scale, qw(-anchor n -tags item));
$c->create(qw(text 21c 17.9c -text Button: -anchor sw));
$c->create(qw(text 21c 20.9c -text Entry: -anchor sw));
$c->create(qw(text 28.5c 17.4c -text Scale: -anchor s));
# Set up event bindings for canvas.
$c->bind('item', '<Any-Enter>' => sub {itemEnter(@_)});
$c->bind('item', '<Any-Leave>' => sub {itemLeave(@_)});
$c->Tk::bind('<1>' => sub {
my($c) = @_;
my $e = $c->XEvent;
itemStartDrag $c, $e->x, $e->y;
});
$c->Tk::bind('<B1-Motion>' => sub {
my($c) = @_;
my $e = $c->XEvent;
itemDrag $c, $e->x, $e->y;
});
$c->Tk::bind('<2>' => sub {
my($c) = @_;
my $e = $c->XEvent;
$c->scan('mark', $e->x, $e->y);
});
$c->Tk::bind('<B2-Motion>' => sub {
my ($c) = @_;
my $e = $c->XEvent;
$c->scan('dragto', $e->x, $e->y);
});
$c->Tk::bind('<3>' => sub {
my($c) = @_;
my $e = $c->XEvent;
itemMark $c, $e->x, $e->y;
});
$c->Tk::bind('<B3-Motion>' => sub {
my($c) = @_;
my $e = $c->XEvent;
itemStroke $c, $e->x, $e->y;
});
$c->Tk::bind('<Control-f>' => sub {
my($c) = @_;
my $e = $c->XEvent;
itemsUnderArea $c;
});
$w->bind('<Any-Enter>' => [sub {
my($w, $c) = @_;
my $e = $c->XEvent;
$c->Tk::focus;
}, $c]);
} # end mkItems
1;