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+#
+# The help widget that provides both "balloon" and "status bar"
+# types of help messages.
+#
+# This is a patched version of Balloon 3.037 - it adds support
+# for different orientations of the balloon widget, depending
+# on wether there's enough space for it. The little arrow now
+# should always point directly to the client.
+# Added by Gerhard Petrowitsch (gerhard.petrowitsch@philips.com)
+#
+# Nov 1, 2003 - Jack Dunnigan
+# Added support for more than one screen in single logical
+# screen mode (i.e. xinerama, dual monitors)
+
+package Tk::Balloon;
+
+use vars qw($VERSION);
+$VERSION = '4.011'; # was: sprintf '4.%03d', q$Revision: #10 $ =~ /\D(\d+)\s*$/;
+
+use Tk qw(Ev Exists);
+use Carp;
+require Tk::Toplevel;
+
+Tk::Widget->Construct('Balloon');
+use base qw(Tk::Toplevel);
+
+# use UNIVERSAL; avoid the UNIVERSAL.pm file subs are XS in perl core
+
+use strict;
+
+my @balloons;
+my $button_up = 0;
+my %arrows = ( TL => 'R0lGODlhBgAGAJEAANnZ2QAAAP///////yH5BAEAAAAALAAAAAAGAAYAAAINjA0HAEdwLCwMKIQfBQA7',
+ TR => 'R0lGODlhBgAGAJEAANnZ2QAAAP///////yH5BAEAAAAALAAAAAAGAAYAAAIRBGMDwAEQkgAIAAoCABEEuwAAOw==',
+ BR => 'R0lGODlhBgAGAJEAANnZ2QAAAP///////yH5BAEAAAAALAAAAAAGAAYAAAIPDOHHhYVRAIgIAEISQLELADs=',
+ BL => 'R0lGODlhBgAGAJEAANnZ2QAAAP///////yH5BAEAAAAALAAAAAAGAAYAAAIPhB1xAUFALCIMKAaAWQAVADs=',
+ NO => 'R0lGODlhAQABAJEAANnZ2f///////////yH5BAEAAAAALAAAAAABAAEAAAICRAEAOw=='
+ );
+
+
+sub ClassInit {
+ my ($class, $mw) = @_;
+ $mw->bind('all', '<Motion>', ['Tk::Balloon::Motion', Ev('X'), Ev('Y'), Ev('s')]);
+ $mw->bind('all', '<Leave>', ['Tk::Balloon::Motion', Ev('X'), Ev('Y'), Ev('s')]);
+ $mw->bind('all', '<Button>', 'Tk::Balloon::ButtonDown');
+ $mw->bind('all', '<ButtonRelease>', 'Tk::Balloon::ButtonUp');
+ return $class;
+}
+
+sub Populate {
+ my ($w, $args) = @_;
+
+ $w->SUPER::Populate($args);
+
+ $w->overrideredirect(1);
+ $w->withdraw;
+ # Only the container frame's background should be black... makes it
+ # look better.
+ $w->configure(-background => 'black');
+
+ # the balloon arrows
+ $w->{img_tl} = $w->Photo(-data => $arrows{TL}, -format => 'gif');
+ $w->{img_tr} = $w->Photo(-data => $arrows{TR}, -format => 'gif');
+ $w->{img_bl} = $w->Photo(-data => $arrows{BL}, -format => 'gif');
+ $w->{img_br} = $w->Photo(-data => $arrows{BR}, -format => 'gif');
+ $w->{img_no} = $w->Photo(-data => $arrows{NO}, -format => 'gif');
+ $w->OnDestroy([$w, '_destroyed']);
+
+ $w->{'pointer'} = $w->Label(-bd=>0, -relief=>'flat',-image=>$w->{img_no});
+
+ # the balloon message
+ # We give the Label a big borderwidth
+ # ..enough to slide a 6x6 gif image along the border including some space
+
+ my $ml = $w->Label(-bd => 0,
+ -padx => 10,
+ -pady => 3,
+ -justify => 'left',
+ -relief=>'flat');
+ $w->Advertise('message' => $ml);
+
+ $ml->pack(
+ -side => 'top',
+ -anchor => 'nw',
+ -expand => 1,
+ -fill => 'both',
+ -padx => 0,
+ -pady => 0);
+
+ # append to global list of balloons
+ push(@balloons, $w);
+ $w->{'popped'} = 0;
+ $w->{'buttonDown'} = 0;
+ $w->{'menu_index'} = 'none';
+ $w->{'menu_index_over'} = 'none';
+ $w->{'canvas_tag'} = '';
+ $w->{'canvas_tag_over'} = '';
+ $w->{'current_screen'} = 0;
+
+ $w->ConfigSpecs(-installcolormap => ['PASSIVE', 'installColormap', 'InstallColormap', 0],
+ -initwait => ['PASSIVE', 'initWait', 'InitWait', 350],
+ -state => ['PASSIVE', 'state', 'State', 'both'],
+ -statusbar => ['PASSIVE', 'statusBar', 'StatusBar', undef],
+ -statusmsg => ['PASSIVE', 'statusMsg', 'StatusMsg', ''],
+ -balloonmsg => ['PASSIVE', 'balloonMsg', 'BalloonMsg', ''],
+ -balloonposition => ['PASSIVE', 'balloonPosition', 'BalloonPosition', 'widget'],
+ -postcommand => ['CALLBACK', 'postCommand', 'PostCommand', undef],
+ -cancelcommand => ['CALLBACK', 'cancelCommand', 'CancelCommand', undef],
+ -motioncommand => ['CALLBACK', 'motionCommand', 'MotionCommand', undef],
+ -background => ['DESCENDANTS', 'background', 'Background', '#C0C080'],
+ -foreground => ['DESCENDANTS', 'foreground', 'Foreground', undef],
+ -font => [$ml, 'font', 'Font', '-*-helvetica-medium-r-normal--*-120-*-*-*-*-*-*'],
+ -borderwidth => ['SELF', 'borderWidth', 'BorderWidth', 1],
+ -numscreens=>['PASSIVE', 'numScreens','NumScreens',1],
+ );
+}
+
+# attach a client to the balloon
+sub attach {
+ my ($w, $client, %args) = @_;
+ foreach my $key (grep(/command$/,keys %args))
+ {
+ $args{$key} = Tk::Callback->new($args{$key});
+ }
+ my $msg = delete $args{-msg};
+ $args{-balloonmsg} = $msg unless exists $args{-balloonmsg};
+ $args{-statusmsg} = $msg unless exists $args{-statusmsg};
+ $w->{'clients'}{$client} = \%args;
+ $client->OnDestroy([$w, 'detach', $client]);
+}
+
+# detach a client from the balloon.
+sub detach {
+ my ($w, $client) = @_;
+ if (Exists($w))
+ {
+ $w->Deactivate if ($client->IS($w->{'client'}));
+ }
+ delete $w->{'clients'}{$client};
+}
+
+sub GetOption
+{
+ my ($w,$opt,$client) = @_;
+ $client = $w->{'client'} unless defined $client;
+ if (defined $client)
+ {
+ my $info = $w->{'clients'}{$client};
+ return $info->{$opt} if exists $info->{$opt};
+ }
+ return $w->cget($opt);
+}
+
+sub Motion {
+ my ($ewin, $x, $y, $s) = @_;
+
+ return if not defined $ewin;
+
+ # Find which window we are over
+ my $over = $ewin->Containing($x, $y);
+
+ return if &grabBad($ewin, $over);
+
+ foreach my $w (@balloons) {
+ # if cursor has moved over the balloon -- ignore
+ next if defined $over and $over->toplevel eq $w;
+
+ # find the client window that matches
+ my $client = $over;
+ while (defined $client) {
+ last if (exists $w->{'clients'}{$client});
+ if ($client->can("MasterMenu")) {
+ my $master = $client->MasterMenu;
+ if ($master && exists $w->{'clients'}{$master}) {
+ $w->{'clients'}{$client} = $w->{'clients'}{$master};
+ last;
+ }
+ }
+ $client = $client->Parent;
+ }
+ if (defined $client) {
+ # popping up disabled -- ignore
+ my $state = $w->GetOption(-state => $client);
+ next if $state eq 'none';
+ # Check if a button was recently released:
+ my $deactivate = 0;
+ if ($button_up) {
+ $deactivate = 1;
+ $button_up = 0;
+ }
+ # Deactivate it if the motioncommand says to:
+ my $command = $w->GetOption(-motioncommand => $client);
+ $deactivate = $command->Call($client, $x, $y) if defined $command;
+ if ($deactivate)
+ {
+ $w->Deactivate;
+ }
+ else
+ {
+ # warn "deact: $client $w->{'client'}";
+ $w->Deactivate unless $client->IS($w->{'client'});
+ my $msg = $client->BalloonInfo($w,$x,$y,'-statusmsg','-balloonmsg');
+ if (defined($msg))
+ {
+ my $delay = delete $w->{'delay'};
+ $delay->cancel if defined $delay;
+ my $initwait = $w->GetOption(-initwait => $client);
+ $w->{'delay'} = $client->after($initwait, sub {$w->SwitchToClient($client);});
+ $w->{'client'} = $client;
+ }
+ }
+ } else {
+ # cursor is at a position covered by a non client
+ # pop down the balloon if it is up or scheduled.
+ $w->Deactivate;
+ }
+ }
+}
+
+sub ButtonDown {
+ my ($ewin) = @_;
+
+ foreach my $w (@balloons) {
+ $w->Deactivate;
+ }
+}
+
+sub ButtonUp {
+ $button_up = 1;
+}
+
+# switch the balloon to a new client
+sub SwitchToClient {
+ my ($w, $client) = @_;
+ return unless Exists($w);
+ return unless Exists($client);
+ return unless $client->IS($w->{'client'});
+ return if &grabBad($w, $client);
+ my $command = $w->GetOption(-postcommand => $client);
+ if (defined $command) {
+ # Execute the user's command and return if it returns false:
+ my $pos = $command->Call($client);
+ return if not $pos;
+ if ($pos =~ /^(\d+),(\d+)$/) {
+ # Save the returned position so the Popup method can use it:
+ $w->{'clients'}{$client}{'postposition'} = [$1, $2];
+ }
+ }
+ my $state = $w->GetOption(-state => $client);
+ $w->Popup if ($state =~ /both|balloon/);
+ $w->SetStatus if ($state =~ /both|status/);
+ $w->{'popped'} = 1;
+ $w->{'delay'} = $w->repeat(200, ['Verify', $w, $client]);
+}
+
+sub grabBad {
+
+ my ($w, $client) = @_;
+
+ return 0 unless Exists($client);
+ my $g = $w->grabCurrent;
+ return 0 unless defined $g;
+ return 0 if $g->isa('Tk::Menu');
+ return 0 if $g eq $client;
+
+ # Ignore grab check if $w is the balloon itself.
+ # XXX Why is this necessary? Is it possible to remove the grabBad
+ # condition in SwitchToClient altogether?
+ return 0 if $w->isa(__PACKAGE__);
+
+ # The grab is OK if $client is a decendant of $g. Use the internal Tcl/Tk
+ # pathname (yes, it's cheating, but it's legal).
+
+ return 0 if $g == $w->MainWindow;
+ my $wp = $w->PathName;
+ my $gp = $g->PathName;
+ return 0 if $wp =~ /^$gp/;
+ return 1; # bad grab
+
+} # end grabBad
+
+
+sub Subclient
+{
+ my ($w,$data) = @_;
+ if (defined($w->{'subclient'}) && (!defined($data) || $w->{'subclient'} ne $data))
+ {
+ $w->Deactivate;
+ }
+ $w->{'subclient'} = $data;
+}
+
+sub Verify {
+ my $w = shift;
+ my $client = shift;
+ my ($X,$Y) = (@_) ? @_ : ($w->pointerxy);
+ my $over = $w->Containing($X,$Y);
+ return if not defined $over or ($over->toplevel eq $w);
+ my $deactivate = # DELETE? or move it to the isa-Menu section?:
+ # ($over ne $client) or
+ not $client->IS($w->{'client'})
+# or (!$client->isa('Tk::Menu') && $w->grabCurrent);
+# or $w->grabbad($client);
+ or &grabBad($w, $client);
+ if ($deactivate)
+ {
+ $w->Deactivate;
+ }
+ else
+ {
+ $client->BalloonInfo($w,$X,$Y,'-statusmsg','-balloonmsg');
+ }
+}
+
+sub Deactivate {
+ my ($w) = @_;
+ my $delay = delete $w->{'delay'};
+ $delay->cancel if defined $delay;
+ if ($w->{'popped'}) {
+ my $client = $w->{'client'};
+ my $command = $w->GetOption(-cancelcommand => $client);
+ if (defined $command) {
+ # Execute the user's command and return if it returns false:
+ return if not $command->Call($client);
+ }
+ $w->withdraw;
+ $w->ClearStatus;
+ $w->{'popped'} = 0;
+ $w->{'menu_index'} = 'none';
+ $w->{'canvas_tag'} = '';
+ }
+ $w->{'client'} = undef;
+ $w->{'subclient'} = undef;
+ $w->{'location'} = undef;
+}
+
+sub Popup {
+ my ($w) = @_;
+ if ($w->cget(-installcolormap)) {
+ $w->colormapwindows($w->winfo('toplevel'))
+ }
+ my $client = $w->{'client'};
+ return if not defined $client or not exists $w->{'clients'}{$client};
+ my $msg = $client->BalloonInfo($w, $w->pointerxy,'-balloonmsg');
+ # Dereference it if it looks like a scalar reference:
+ $msg = $$msg if UNIVERSAL::isa($msg, 'SCALAR');
+
+ $w->Subwidget('message')->configure(-text => $msg);
+ $w->idletasks;
+
+ return unless Exists($w);
+ return unless Exists($client);
+ return if $msg eq ''; # Don't popup empty balloons.
+
+ my ($x, $y);
+ my $pos = $w->GetOption(-balloonposition => $client);
+ my $postpos = delete $w->{'clients'}{$client}{'postposition'};
+ if (defined $postpos) {
+ # The postcommand must have returned a position for the balloon - I will use that:
+ ($x,$y) = @{$postpos};
+ } elsif ($pos eq 'mouse') {
+ ($x,$y)=$client->pointerxy; # We adjust the position later
+ } elsif ($pos eq 'widget') {
+ $x = int($client->rootx + $client->width/2);
+ $y = int($client->rooty + int ($client->height/1.3));
+ } else {
+ croak "'$pos' is not a valid position for the balloon - it must be one of: 'widget', 'mouse'.";
+ }
+
+ $w->idletasks;
+
+ # Explanation of following code. [JD]
+ # PREMISE: We want to ensure that the balloon is always "on screen".
+ # To do this we use calculate the size of the
+ # toplevel before it is mapped. Then we adjust it's position with respect to the
+ # mouse cursor or widget. Balloons are usually shown below and to the right of the target.
+ # From extensive KDE experience using Xinerama, and from using dual monitors on WinXP..
+ # the balloon will extend across two monitors in single logical screen mode (SLS).
+ # This is an undesirable characteristic indeed. Trying to read a disjointed balloon
+ # across monitors is not fun.
+ #
+ # The intent of the following code is to fix this problem. We do this by avoiding
+ # placement of any part of the balloon over,say, the "half screenwidth" mark (for two
+ # monitors in SLS mode) or "thirds of screenwidth" mark (for 3 monitors) and so on...
+ # i.e. In SLS mode these *WILL BE* separate screens and as such, should be considered hard
+ # boundaries to be avoided.
+ #
+ # The only drawback of this code, is I know of no way to actually determine this on a
+ # user by user basis. This means that the developer or administrator will have to know
+ # the hardware (monitor) setup for which the application is designed.
+ #
+ # This code uses Gerhard's GIF images but changes *how* the image gets shown. Instead
+ # of creating four separate labels, we configure only ONE label with the proper image.
+ # Then using the place geometry manager, this image/label can be "slid" along the
+ # appropriate side of the toplevel so that it always points directly at the target widget.
+ #
+ # Here we go..
+
+ my ($width, $height) = ($w->reqwidth, $w->reqheight);
+ my ($sw, $sh) = ($w->screenwidth, $w->screenheight);
+ my $numscreen = $w->cget(-numscreens);
+ my $deltax = $sw/$numscreen;
+ my $leftedge;
+ my $rightedge;
+ my $count = 0;
+ for (my $i=0; $i<$sw; $i+=$deltax){
+ $leftedge = $i;
+ $rightedge = $i + $deltax;
+ if ($x >= $leftedge && $x < $rightedge ){
+ last;
+ }
+ $count++;
+ }
+
+ # Force another look at balloon location because mouse has switched
+ # virtual screens.
+ $w->{'location'} = undef unless ( $count == $w->{'current_screen'} );
+ $w->{'current_screen'} = $count;
+
+ my $xx=undef;
+ my $yy=undef; # to hold final toplevel placement
+ my $slideOffsetX = 0;
+ my $slideOffsetY = 0;
+ my $cornerOffset = 5; #default - keep corner away from pointer
+ my $testtop = $y - $height - $cornerOffset;
+ my $testbottom = $y + $height + (2*$cornerOffset);
+ my $testright = $x + $width + (2*$cornerOffset);
+ my $testleft = $x - $width - $cornerOffset;
+ my $vert='bottom'; #default
+ my $horiz='right'; #default
+
+
+ if ( defined $w->{'location'} ){
+ # Once balloon is activated, **don't** change the location of the balloon.
+ # It is annoying to have it jump from one location to another.
+ ( $w->{'location'}=~/top/ ) ? ( $vert = 'top' ) : ( $vert = 'bottom' );
+ ( $w->{'location'}=~/left/ ) ? ( $horiz = 'left' ) : ( $horiz = 'right' );
+
+ if ($vert eq 'top' && $testtop < 0) {
+ $yy = 0;
+ $slideOffsetY = $testtop;
+ }
+ elsif ($vert eq 'bottom' && $testbottom > $sh) {
+ $slideOffsetY = $testbottom - $sh;
+ }
+
+ if ($horiz eq 'left' && $testleft < $leftedge) {
+ $xx = $leftedge;
+ }
+ elsif ($horiz eq 'right' && $testright > $rightedge) {
+ $slideOffsetX = $testright - $rightedge;
+ }
+ }
+ else {
+ #Test balloon positions in the vertical
+ if ($testbottom > $sh) {
+ #Then offscreen to bottom, check top
+ if ($testtop >= 0) {
+ $vert = 'top';
+ }
+ elsif ($y > $sh/2) {
+ #still offscreen to top but there is more room above then below
+ $vert = 'top';
+ $yy=0;
+ $slideOffsetY = $testtop;
+ }
+ if ($vert eq 'bottom'){
+ #Calculate Yoffset to fit entire balloon onto screen
+ $slideOffsetY = $testbottom - $sh;
+ }
+ }
+ #Test balloon positions in the horizontal
+
+ if ($testright > $rightedge) {
+ #The offscreen, check left
+ if ($testleft >= $leftedge) {
+ $horiz = 'left';
+ }
+ elsif ($x > ($leftedge+$deltax) ) {
+ #still offscreen to left but there is more room to left than right
+ $horiz = 'left';
+ $xx=0;
+ $slideOffsetX = $testleft;
+ }
+ if ($horiz eq 'right'){
+ #Calculate Xoffset to fit entire balloon onto screen
+ $slideOffsetX = $testright - $rightedge;
+ }
+ }
+ }
+
+ $w->{'location'} = $vert.$horiz unless (defined $w->{'location'});
+
+ if ($w->{'location'} eq 'bottomright') {
+ if ( $slideOffsetX or $slideOffsetY ) {
+ $w->{'pointer'}->configure(-image => $w->{img_no});
+ }
+ else {
+ $w->{'pointer'}->configure(-image => $w->{img_tl});
+ }
+
+ $w->{'pointer'}->place(
+ -in=>$w,
+# -relx=>0, -x=>$slideOffsetX + 2,
+# -rely=>0, -y=>$slideOffsetY + 2,
+ -relx=>0, -x=>2,
+ -rely=>0, -y=>2,
+ -bordermode=>'outside',
+ -anchor=>'nw');
+
+ $xx=$x-$slideOffsetX+(2*$cornerOffset) unless (defined $xx);
+ $yy=$y-$slideOffsetY+(2*$cornerOffset) unless (defined $yy);
+
+ }
+ elsif ($w->{'location'} eq 'bottomleft') {
+ if ( $slideOffsetX or $slideOffsetY ) {
+ $w->{'pointer'}->configure(-image => $w->{img_no});
+ }
+ else {
+ $w->{'pointer'}->configure(-image => $w->{img_tr});
+ }
+
+ $w->{'pointer'}->place(-in=>$w,
+# -relx=>1, -x=>$slideOffsetX - 2,
+# -rely=>0, -y=>$slideOffsetY + 2,
+ -relx=>1, -x=>-2,
+ -rely=>0, -y=>2,
+ -bordermode=>'outside',
+ -anchor=>'ne');
+
+ $xx=$x-$width-$slideOffsetX-$cornerOffset unless (defined $xx);
+ $yy=$y-$slideOffsetY+(2*$cornerOffset) unless (defined $yy);
+
+ }
+ elsif ($w->{'location'} eq 'topright') {
+ if ( $slideOffsetX or $slideOffsetY ) {
+ $w->{'pointer'}->configure(-image => $w->{img_no});
+ }
+ else {
+ $w->{'pointer'}->configure(-image => $w->{img_bl});
+ }
+
+ $w->{'pointer'}->place(-in=>$w,
+# -relx=>0, -x=>$slideOffsetX + 2,
+# -rely=>1, -y=>$slideOffsetY - 2,
+ -relx=>0, -x=>2,
+ -rely=>1, -y=>-2,
+ -bordermode=>'outside',
+ -anchor=>'sw');
+
+ $xx=$x-$slideOffsetX+$cornerOffset unless (defined $xx);
+ $yy=$y-$height-$slideOffsetY-$cornerOffset unless (defined $yy);
+ }
+ elsif ($w->{'location'} eq 'topleft') {
+ if ( $slideOffsetX or $slideOffsetY ) {
+ $w->{'pointer'}->configure(-image => $w->{img_no});
+ }
+ else {
+ $w->{'pointer'}->configure(-image => $w->{img_br});
+ }
+
+ $w->{'pointer'}->place(-in=>$w,
+# -relx=>1, -x=>$slideOffsetX - 2,
+# -rely=>1, -y=>$slideOffsetY - 2,
+ -relx=>1, -x=>-2,
+ -rely=>1, -y=>-2,
+ -bordermode=>'outside',
+ -anchor=>'se');
+
+ $xx=$x-$width-$slideOffsetX-$cornerOffset unless (defined $xx);
+ $yy=$y-$height-$slideOffsetY-$cornerOffset unless (defined $yy);
+ }
+
+ $w->{'pointer'}->raise;
+ $xx = int($xx);
+ $yy = int($yy);
+ $w->geometry("+$xx+$yy");
+ $w->deiconify();
+ $w->raise;
+}
+
+sub SetStatus {
+ my ($w) = @_;
+ my $client = $w->{'client'};
+ my $s = $w->GetOption(-statusbar => $client);
+ if (defined $s and $s->winfo('exists')) {
+ my $vref = $s->cget(-textvariable);
+ return if not defined $client or not exists $w->{'clients'}{$client};
+ my $msg = $client->BalloonInfo($w, $w->pointerxy,'-statusmsg');
+ # Dereference it if it looks like a scalar reference:
+ $msg = $$msg if UNIVERSAL::isa($msg, 'SCALAR');
+ if (not defined $vref) {
+ eval { $s->configure(-text => $msg); };
+ } else {
+ $$vref = $msg;
+ }
+ }
+}
+
+sub ClearStatus {
+ my ($w) = @_;
+ my $client = $w->{'client'};
+ my $s = $w->GetOption(-statusbar => $client);
+ if (defined $s and $s->winfo('exists')) {
+ my $vref = $s->cget(-textvariable);
+ if (defined $vref) {
+ $$vref = '';
+ } else {
+ eval { $s->configure(-text => ''); }
+ }
+ }
+}
+
+sub _destroyed {
+ my ($w) = @_;
+ # This is called when widget is destroyed (no matter how!)
+ # via the ->OnDestroy hook set in Populate.
+ # remove ourselves from the list of baloons.
+ @balloons = grep($w != $_, @balloons);
+
+ # FIXME: If @balloons is now empty perhaps remove the 'all' bindings
+ # to reduce overhead until another balloon is created?
+
+ # Delete the images
+ for (qw(no tl tr bl br)) {
+ my $img = delete $w->{"img_$_"};
+ $img->delete if defined $img;
+ }
+}
+
+1;
+
+