[RESOLVED] Class within a class?

[mrbaseball34]

I am writing a class which extends another class.
In this class, I need to instantiate yet another class.

Is it possible to do something like this:

class ReportGenerator extends ObjectModel
{

  require_once('tcpdf/config/lang/eng.php');
  require_once('tcpdf/tcpdf.php');

  // extend TCPF with custom functions
  class MYPDF extends TCPDF {

// some overrirdden TCPDF class methods going here.

  }

  // DO a whole lot of things to build the PDF file.

}

[Res]

No, you cannot define a class inside of a class like this. You need to restructure them to inherit what you need while perserving your ablitity to override in subclassing, or pass the objects you need inside the class to the constructor.

  class MYPDF extends TCPDF {

// some overrirdden TCPDF class methods going here.

  } 
class ReportGenerator extends ObjectModel
{
    public $pdf_obj;  

public function __constructor(MYPDF $pdf_obj){
   $this->pdf_obj = $pdf_obj;
}

public function foo(){
   $this->pdf_obj->foo();
}
}

[mrbaseball34]

Folks over at Experts-Exchange seem to think differently.

[Res]

I'm going to think the same way the PHP parser thinks, not "Experts"-Exchange.

The results of a class block inside of a class block

Parse error: syntax error, unexpected T_CLASS, expecting T_FUNCTION

[NogDog]

You can instantiate another class within a class, but not define it. Generally I prefer not to, as it sort of hides the dependency within the guts of the class, as opposed to when you pass it as a parameter to it.

class A {
   public function foo()
   {
      return "bar";
   }
}

/* self-instantiate it */
class B
{
   private $a;
   public function __construct()
   {
      $this->a = new A();
   }
   public function foo()
   {
      echo $this->a->foo();
   }
}

/* pass it as a parameter */
class C
{
   private $a;
   public function __construct(A $a) // it's obvious C depends on A
   {
      $this->a = $a;
   }
   public function foo()
   {
      echo $this->a->foo();
   }
}

$test1 = new B();
$test1->foo();
$test2 = new C(new A()); 
$test1->foo();

[mrbaseball34]

I can't seem to get this to work at all. I get no errors, it just doesn't work. I can tell be cause when I try to call the BuildReport function of the ReportGenerator class, it basically does nothing.

Tools:😃ebugLog is supposed to log a record to a table with the message
passed as second parameter.

require_once(dirname(__FILE__).'/../tcpdf/config/lang/eng.php');
require_once(dirname(__FILE__).'/../tcpdf/tcpdf.php');

// extend TCPF with custom functions
class MYPDF extends TCPDF {

  var $partno;

  function __construct() {
    // wonder why there are no params passed into here
    parent::__construct();   

  } // Constructor

  public function setPartNo($part) {
    $this->partno = $part;
  } // public function setPartNo($part) 

 // ---------------------------------------------------------
 // This function returns an array of RGB values to use
 // for TCPDF function calls that require color  values
 // ---------------------------------------------------------
  private function html2rgb($color) {
    <SNIP>    

    return array($r, $g, $b);
  } // private function html2rgb($color)

  // ---------------------------------------------------------
  // Outputs a 4pt height blank line.
  // ---------------------------------------------------------
  public function blankLine() {
    <SNIP>    

  } // public function blankLine()

  // ---------------------------------------------------------
  // Returns the width in units based on percentage of pagewidth
  // minus the margins.
  // if you want to include the margins, set second param
  // to false
  // ---------------------------------------------------------
  public function getColumnWidthByPct($pct, $excludeMargins=true) {
    <SNIP>    

    return ($pagew * ($pct/100));
  } // public function getColumnWidthByPct($pct, $excludeMargins=true)

  // ---------------------------------------------------------
  // Sets the Fill Color from an HTML color value
  // ---------------------------------------------------------
  public function setTitleColor($htmlcolor) {
    <SNIP>    

  }

  // ---------------------------------------------------------
  // Sets the Fill Color from an HTML color value
  // ---------------------------------------------------------
  public function setLineColor($htmlcolor) {
    <SNIP>    

  } // public function setLineColor($htmlcolor)

  // ---------------------------------------------------------
  // Prints a header row
  // ---------------------------------------------------------
  public function doRowHeader($header, $headerColInfo, $headerHt=4, $fontht=10) {
    <SNIP>    

  } // public function doRowHeader($header, $headerColInfo, $headerHt=4, $fontht=10)

  // ---------------------------------------------------------
  // Prints row of $result
  // ---------------------------------------------------------
  public function doRows($dbresult, $columnInfo) {
    <SNIP>    

  } // public function doRows($dbresult, $columnInfo)

  // ---------------------------------------------------------
  // Prints a header row containing a Photo
  // ---------------------------------------------------------
  public function doPhotoRow($imagelink) {
    <SNIP>    

  } // public function doPhotoRow($imagelink)

  // ---------------------------------------------------------
  // Prints the footer
  // ---------------------------------------------------------
  public function Footer() 
  { 
    <SNIP>    

  } // public function Footer() 
} // end class MYPDF extends TCPDF

class  ReportGenerator extends ObjectModel
{
  public $pdf_obj;

   public function __construct()
  {
    parent::__construct();
    // The constants being passed in the MYPDF constructor are in tcpdf_config, 
    // which is called from tcpdf.php
    $this->pdf_obj = new MYPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true, 'UTF-8', false); 
  } // Constructor

  // ---------------------------------------------------------
  // Strips "Illegal" characters from a string
  // ---------------------------------------------------------
  public function stripIllegalChars($v) {
    <SNIP>    

    return $value;
  }  function stripIllegalChars($v)

  public function BuildReport($filename, $partno) {
    $pdf_obj->setPartNo($partno);
     Tools::DebugLog('ReportGenerator', 'In BuildReport');
    return true;
  } // function BuildReport($filename, $partno)

} // class  ReportGenerator extends ObjectModel

[Res]

I haven't been able to track down exactly what causes it, but I have had the exact same issue when using non-instantiated objects. The call should work, and will work outside of the class it's wrapped in (in my case), but for what ever reason does not work inside of a class file.

I have to do this to get it to work, even though it should work.

//inside classes only this works
$tool = new Tool();
$tool->foo();
//this doesn't work, even though it shoudl and does outside of the class
Tool::foo();

All else fails start peppering it with echo statements, see where it's getting and at what point it stops getting.

[NogDog]

You left a $this-> out of this method:

  public function BuildReport($filename, $partno) {
    [color=red]$this->[/color]pdf_obj->setPartNo($partno);
     Tools::DebugLog('ReportGenerator', 'In BuildReport');
    return true;
  }

[mrbaseball34]

DUH,me!

thanks...