function __construct()
 {
     if ($this->ansicht == null) {
         $this->ansicht = "monat";
     }
     $display = mUserdata::getUDValueS("KalenderDisplay" . ucfirst($this->ansicht), "0");
     switch ($this->ansicht) {
         case "jahr":
             $Date = new Datum(Datum::parseGerDate("1.1." . date("Y")));
             for ($i = 0; $i < abs($display); $i++) {
                 if ($display > 0) {
                     $Date->addYear();
                 } else {
                     $Date->subYear();
                 }
             }
             break;
         case "monat":
             $Date = new Datum(Datum::parseGerDate("1." . date("m.Y")));
             for ($i = 0; $i < abs($display); $i++) {
                 if ($display > 0) {
                     $Date->addMonth();
                 } else {
                     $Date->subMonth();
                 }
             }
             break;
         case "woche":
             $Date = new Datum(Datum::parseGerDate(date("d.m.Y")));
             for ($i = 0; $i < abs($display); $i++) {
                 if ($display > 0) {
                     $Date->addWeek(true);
                 } else {
                     $Date->subWeek();
                 }
             }
             break;
         case "tag":
             $Date = new Datum(Datum::parseGerDate(date("d.m.Y")));
             for ($i = 0; $i < abs($display); $i++) {
                 if ($display > 0) {
                     $Date->addDay();
                 } else {
                     $Date->subDay();
                 }
             }
             break;
     }
     $this->current = clone $Date;
     if ($this->ansicht != "tag" and $this->ansicht != "jahr") {
         while (date("w", $Date->time()) > 1) {
             $Date->subDay();
         }
         if (date("w", $Date->time()) == 0) {
             $Date->addDay();
         }
     }
     $this->date = $Date;
     $this->first = $Date->time();
     $D = clone $Date;
     $rows = 5;
     if ($this->ansicht == "woche") {
         $rows = 1;
     }
     $cols = 7;
     if ($this->ansicht == "tag") {
         $cols = 1;
         $rows = 1;
     }
     if ($this->ansicht == "jahr") {
         $cols = 31;
         $rows = 12;
     }
     if ($this->ansicht != "jahr") {
         for ($i = 0; $i < $rows; $i++) {
             if ($i > 0 and date("m.Y", $D->time()) != date("m.Y", $this->current->time())) {
                 break;
             }
             for ($j = 0; $j < 7; $j++) {
                 $D->addDay();
             }
         }
         $D->subDay();
     }
     if ($this->ansicht == "jahr") {
         $D->addYear();
         $D->subDay();
     }
     $this->rows = $rows;
     $this->cols = $cols;
     $this->last = $D->time();
 }