Doing onDoubleClicked : { text.horizontalAlignment = AlignHCenter;} doesn't display a warning

import Qt 4.6

Rectangle {
   color : "red"
   width : 300
   height : 300
   Rectangle {
       color : "white"
       x : 70
       y : 70
       width : 100
       height : 50
       TextInput {
           id : text
           anchors.fill : parent
       }
  }
  MouseArea {
      width : 50
      height : 50
      onDoubleClicked : { text.horizontalAlignment = AlignHCenter; console.log("DoubleClicked");}
  }
}