How to Read _droptarget property in ActionScript

Drag blue rectangle over the yellow. If you drop the blue one on the yellow, the script will align blue rectangle inside the yellow.

Follow the steps below:

1. Launch Flash Designer and choose “blank”.
2. Set the frame delay to “Stop” (“Frame” > “Frame Delay”).
3. Size the frame at about 300×300. (“Frame” > “Frame Size”)
4. Create 1 small and 1 larger shapes with the rectangle tool and give them different fill colors.
5. Select smaller shape and click Edit > Convert to Sprite.
6. Right-click it and click “Placement Properties”.
7. Check the “Action-Script Target” checkbox and click OK.
8. Click the other shape and repeat the process.

Smaller shape (blue) should appear as “Sprite3″ and larger (yellow) as “Sprite4″. If necessary rename the sprite: select it and choose “Item” > “Placement Properties”

Choose “Frame” > “ActionScript” and paste the code:
Sprite3.onPress = function()
{
Sprite3.startDrag();
};
Sprite3.onRelease = function()
{
if(Sprite3._droptarget==”/Sprite4″)
{
// align Sprite3
Sprite3._x = Sprite4._x + (Sprite4._width-Sprite3._width)/2;
Sprite3._y = Sprite4._y + (Sprite4._height-Sprite3._height)/2;
};
Sprite3.stopDrag();
};

Press F9 to preview the movie.

_droptarget always returns the path with a leading slash /.

Download source project here