Dragging a line drawn with addLineTool() function

[pj909]

Is it possible drag a line that you have drawn using addLineTool() function.
Tried that with this script - can't move lines by click, drag & drop.

/*********************************************************
Plot Profit Targets and Stop Loss
**********************************************************/
var aFPArray = new Array();
var SL = 0;
var P1 = 0;
var P2 = 0;
function preMain() {

    setPriceStudy(true);
    setStudyTitle("PTSL");
    var x=0;
    aFPArray[x] = new FunctionParameter( "SL", FunctionParameter.NUMBER);
    with( aFPArray[x] ) {
        setName("Stop Loss");
        setLowerLimit( 0 );
        setDefault( 0 );
    }
    x++;
    aFPArray[x] = new FunctionParameter( "P1", FunctionParameter.NUMBER);
    with( aFPArray[x] ) {
        setName("Prfoit Target 1");
        setLowerLimit( 0 );
        setDefault( 0 );    
    }
    x++;
    aFPArray[x] = new FunctionParameter( "P2", FunctionParameter.NUMBER);
    with( aFPArray[x] ) {
        setName("Prfoit Target 2");
        setLowerLimit( 0 );
        setDefault( 0 );
    }
}


function main(SL, P1, P2) {
// on click:      askForInput( "Targets" ); 

    if ( getCurrentBarIndex() == 0 ) {
    addLineTool(LineTool.HORZ, SL, 1, Color.red, "SL");
    addLineTool(LineTool.HORZ, P1, 1, Color.aqua, "P1");
    addLineTool(LineTool.HORZ, P2, 1, Color.blue, "P2");
    }

    return;
} 

With hand drwan lines clicking on the line adds a a "target box" to the cursor. This doesn't appear.