Re: Auto-adjust row height to line wrap in Tk-Tablematrix

[BrowserUk]

Making no claim to understanding tcl; what the code appears to be doing is:

1. for each row in the table;
2. query the text for each column within that row;
3. split that text on newlines;
4. find the maximum number of lines in any column within that row;
5. set the row height for that row accordingly.

SOmething roughly equivalent in Perl terms to:

my $maxRows = $tableMatrix->cget( -rows );
my $maxCols = $tableMatrix->cget( -cols );
for my $r ( 1 .. $maxRows -1 ) {
    set $maxHeight = 1;
    for my $col ( 0 .. $maxCols - 1 ) {
        my $text = $tableMatrix->getText( -row => $row, -col => $col )
+;
        my $nLines = scalar split "\n", $text;
        if( $nLines > 1 and $maxHeight < $nLines ) {
            $maxHeight = $nLines;
        }
    }
    $tableMatrix->cset( row => $row, height => $maxHeight );
}

You'll have to work out the appropriate methods to call for what I've shown as getText() & cset().

[elef]

This seems to assume that there are \n characters in the strings. I am using -wrap => 1, to get automatic line wraps, and I don't think that it inserts \n in the string. It just displays it wrapped without altering the string itself, so I don't think my $nLines = scalar split "\n", $text; would work. But I've been wrong before...
Of course I could perhaps query the width of each column, use a monospace font and do the line wraps myself with \n, in which case of course I would know how many lines each cell is wrapped into, and I could set the height accordingly. But that would essentially mean that I'm rewriting the functionality of -wrap from scratch. There should be a better way - to be honest, I don't really see the usefulness of -wrap if there is no height auto-adjustment functionality. Instead of hanging off the cell to the right, text just ends up hanging off the top and bottom.

[BrowserUk]

This seems to assume that there are \n characters in the strings. I am using -wrap => 1, to get automatic line wraps, and I don't think that it inserts \n in the string.

Hm. I could be wrong, but I'd bet my bottom dollar that wrap is implemented by inserting newlines into the text.

This part of the tcl code:if {[set n [llength [split [.table get $r,$c] \n]]]>1 && $maxh<$n} { breaks down to:

1. Get the text from cell $r, $c: [.table get $r,$c]
2. Split that text on newlines: [split $text \n]
3. Calculate the list length of the result from split: [llength <list> ]
4. Set n to that value: [set n $length ]
5. If the number of lines is greater than one; and greater than the current value of maxh(eight), then set maxh to n;

   (Note: that first test is redundant.)

You would be wasting your time doing font calculations yourself, cos the tablematrix must already be doing them in order to perform the wrapping.

[elef]

I did some testing, \n not found.


use Tk;
use Tk::Dialog;
use Tk::TableMatrix;


my $mw = MainWindow->new;
$mw->minsize(600, 300);        # minimum size of main window in pixels
+    

my $textfont = '-*-Helvetica-Medium-R-Normal--*-140-*-*-*-*-*-*';


my $arrayVar = {};


while (<DATA>) {
    my $i = $. - 1;
    /^([^\t]*)\t([^\t]*)/;
    $arrayVar->{"$i,0"} = "$1";
    $arrayVar->{"$i,1"} = "$2";
}



my $t = $mw->Scrolled('TableMatrix', 
                    -scrollbars => "osoe",
                    -font   => $textfont,
                    -resizeborders => 'none',
                    -rows => 3,
                    -cols => 2,
                    -wrap => 1,
                    -rowheight => 4,
                    -variable => $arrayVar,
                    -colstretchmode => 'all',
                    );

my $buttexit = $mw->Button( -text => "Exit", -command => sub{ $mw->des
+troy});            

my $buttinfo = $mw->Button( -text => "View cellinfo", -command => sub{
    my $cursorpos = $t->icursor();
    my $activecont = $t->get(active);
    my $activeindex = $t->index('active');
    my $linebreak;
    if ($activecont =~ /\n/) {$linebreak = "found"} else {$linebreak =
+ "not found"};
    
    $mw->Dialog(    -title => 'Info', 
                                -text => "current cell contains:\n\n$a
+ctivecont\n\nindex of active cell: $activeindex\nCursor position with
+in cell: $cursorpos\n\nLine break $linebreak", 
                                -default_button => 'OK',
                                -buttons => ['OK']
                            )->Show( );
});    



$t->pack(-expand => 1, -fill => 'both');
$buttexit->pack(-expand => 1, -fill => 'both');
$buttinfo->pack(-expand => 1, -fill => 'both');



Tk::MainLoop;

__DATA__
this is a relatively long string that will probably end up displayed o
+n two lines if the window isn't wide enough    blabla
foo    bar
tralla    lalala



When I click into the cell with the long text and click the View cell info button, the dialog shows the text without line breaks and reports that \n is "not found".
Am I doing something wrong or is this approach a dead end?