Maxxus PRO SPK-23 Especificaciones descargar pdf (Pagina 750)

100

101

Displaying the Articles

Let’s look at the display_tree() function, shown in Listing 29.4.

LISTING 29.4 display_tree() Function from output_fns.php—Creates the Root Node of

the Tree Structure

function display_tree($expanded, $row = 0, $start = 0)

{

// display the tree view of conversations

global $table_width;

echo “<table width = $table_width>”;

// see if we are displaying the whole list or a sublist

if($start>0)

$sublist = true;

else

$sublist = false;

// construct tree structure to represent conversation summary

$tree = new treenode($start, ‘’, ‘’, ‘’, 1, true, -1, $expanded, $sublist);

// tell tree to display itself

$tree->display($row, $sublist);

echo “</table>”;

}

The main role of this function is to create the root node of the tree structure. We use it both to

display the whole index and to create subtrees of replies on the

view_post.php page. As you

can see, it takes three parameters. The first, $expanded, is the list of article postids to display

in an expanded fashion. The second, $row, is an indicator of the row number which will be

used to work out the alternating colors of the rows in the list.

The third parameter, $start, tells the function where to start displaying articles. This is the

postid of the root node for the tree to be created and displayed. If we are displaying the whole

thing, as we are on the main page, this will be 0 (zero), meaning display all the articles with no

parent. If this parameter is 0, we set $sublist to false and display the whole tree.

If the parameter is greater than 0, we use it as the root node of the tree to display, set $sublist to

true and build and display only part of the tree. (We will use this in the view_post.php script.)

The most important thing this function does is instantiate an instance of the treenode class

that represents the root of the tree. This is not actually an article but it acts as the parent of all

Building Practical PHP and MySQL Projects

ART V

724

35 7842 CH29 3/6/01 3:34 PM Page 724

1 2 ... 745 746 747 748 749 750 751 752 753 754 755 ... 892 893

Comentarios a estos manuales

Sin comentarios

Maxxus PRO SPK-23 Especificaciones Pagina 750

Comentarios a estos manuales

Relacionado con productos y manuales para Bicicletas de spin Maxxus PRO SPK-23