The Subselection Tool
The Subselection tool is used to adjust straight segments by changing the angle or length of the segment or to adjust curved segments by changing the slope or direction of the curve. Use it on objects drawn with the Pen tool or on objects drawn with most other tools.
Ungrouped objects will interact with each other which can cause some undesirable effects. They will take a "bite" out of the bottom object if the two objects are different colors, or if they are the same color and overlap, they will react as one object.
NOTE: If your two objects are different colors, selecting one of them after they've been allowed to overlap and moving it will result in a "bite" taken out of the bottom one.
As you can see, this could cause some major problems so Flash gives us a way to keep our objects looking the way we designed them so they don't merge together or eat each other up.
Ungrouping is as simple as going Modify/Ungroup or pressing Ctrl+Shift+G (Ctrl+B also works) while your grouped object is selected.
Editing a Grouped ObjectTo edit a grouped object, you have a couple of choices… You can Ungroup it as mentioned above, or you can double click on it with the Arrow tool. This will cause the rest of your work area to "dim" and give you access to the object. You can then use the other tools to make your changes. You will see appear above the stage which indicates editing mode of the selected object. Once you've finished the editing, just double click with the Arrow tool on the dimmed section of the stage (off the object) and it will go back to it's grouped state. Or click on the Scene 1 link to the left as shown in the third image below.
NOTE: When you know that an object in a movie will only be used once, such as a background or text (which naturally has grouped behavior), it's okay to leave that object as a grouped object rather than converting it to a symbol.
Breaking up text...
While working with the Text Tool you probably noticed the outline
that surrounds text. As mentioned above, this outline indicates a
"grouped" object. Flash automatically gives text grouped behavior. You
also learned that you can break apart text into individual letters. Since
the text in Flash is vector based, it can be broken apart and
"ungrouped", then reshaped much the same as Fills and Lines. This can be a really neat thing to do to the first letter in a
paragraph to give it a unique look, or to change one letter throughout
your text area.
Let's try it...
When you create an object it will be on the lowest level of the layer.
Create another one and it is still on the same lowest level. This is why
ungrouped objects will segment or mingle with each other depending on
whether they are the same color or different colors. Grouping them creates
sublayers on the layer. You can arrange or stack these groups/sublayers by
using the Arrange menu. Find it by going Modify/Arrange.
NOTE: This same effect could be obtained by using layers but it's really best to use a single layer as often as you can so that your movie doesn't end up being impossible to maneuver through.