How to redraw or repaint surface in ExtJS5?

I define a drawing panel and some components which are connected each other with SVG paths. I need to redraw connection paths on surface when moving components. there is my drawing panel

{
    xtype : 'panel',
    flex : 5,
    split : true,
    region : 'center',
    plain : true,
    itemId : 'idCenterRegion',
    id : 'centerRegion',
    border : 1,
    layout : {
        type : 'fit',
    },
    defaults : {
        autoScroll : true
    },
    listeners : {
     afterrender : 'setDDTarget'
    },
    items: [{
        xtype : 'draw',
        itemId : 'idDrawPanel',
        renderTo:Ext.getCmp('centerRegion'),
    }]
    }

The floating windows are adding to centerregion with draw/drop. there is another controller to draw sprites on surface,

printPath : function(drawItem) {
    var source=drawItem.source;
    var target=drawItem.target;

    var surface = Ext.getCmp('centerRegion').down('draw')
            .getSurface('main');
    var color = "#000";

    var line1,line2;

    var posSource=[];
    var posTarget=[];
    if(source.left<target.left){
        posSource[0]=source.left+source.width;
        posTarget[0]=target.left;
        line1=15;
        line2=-15;
    }else{
        posSource[0]=source.left;
        posTarget[0]=target.left+target.width;
        line1=-15;
        line2=15;
    }

    posSource[1]=source.top+source.height/2;
    posTarget[1]=target.top+target.height/2;

    var path = [ "M", posSource[0],
                 posSource[1], "H",
                 posSource[0] + line1, "L",
                 posTarget[0] + line2, posTarget[1], "H",
                 posTarget[0] ].join(",");

    surface.add({
        type : 'path',
        path : path,
        stroke : color,
        fill : 'none',
        'stroke-width' : 2,
        surface : surface,
    }).show(true);

},

When connecting any items on this panel it draws sprites but not showing on browser. but if I re-size drawing panel or browser window, sprites are shown, I couldn't find any reason why its happening.

should I refresh view by using a different way?

That is the result before re-sizing screen, but add sprite method completed successfully.

This screenshot is after re-size height of center region, as you see, sprite is visible now. But any event didn't fire manually on re-size action.