Sprite - StartDrag

Code

var stage = new Stage("canvas", 420, 500, 30);

var sprite = new Sprite();
sprite.x = 50;
sprite.y = 50;
sprite.graphics.lineStyle(0);
sprite.graphics.beginFill(0xFF0000);
sprite.graphics.drawCircle(0, 0, 30);
sprite.graphics.endFill();
sprite.addEventListener(MouseEvent.MOUSE_DOWN, function(e)
{
    sprite.startDrag();
});
sprite.addEventListener(MouseEvent.MOUSE_UP, function(e)
{
    sprite.stopDrag();
});
stage.addChild(sprite);

//lock center
var sprite2 = new Sprite();
sprite2.x = 50;
sprite2.y = 150;
sprite2.graphics.lineStyle(0);
sprite2.graphics.beginFill(0x00FF00);
sprite2.graphics.drawCircle(0, 0, 30);
sprite2.graphics.endFill();
sprite2.addEventListener(MouseEvent.MOUSE_DOWN, function(e)
{
    //lock center
    sprite2.startDrag(true);
});
sprite2.addEventListener(MouseEvent.MOUSE_UP, function(e)
{
    sprite2.stopDrag();
});
stage.addChild(sprite2);

//bounds
var container = new Sprite();
container.x = 50;
container.y = 250;
container.graphics.lineStyle(1, 0x999999);
container.graphics.drawRect(0, 0, 300, 200);
stage.addChild(container);

var sprite3 = new Sprite();
sprite3.graphics.lineStyle(0);
sprite3.graphics.beginFill(0x0000FF);
sprite3.graphics.drawCircle(0, 0, 30);
sprite3.graphics.endFill();
sprite3.addEventListener(MouseEvent.MOUSE_DOWN, function(e)
{
    //limit drag area
    sprite3.startDrag(false, new Rectangle(0, 0, 300, 200));
});
sprite3.addEventListener(MouseEvent.MOUSE_UP, function(e)
{
    sprite3.stopDrag();
});
container.addChild(sprite3);

Canvas

Output