Making items draggable

How are objects made draggable on iphone?

How is an item/object moved by the user. e.g. apps can be moved on the homescreen and they icons follow the users finger.

How can e.g. a tableview cell contents be moved if the user holds down on it and then moves their finger?

What controls the movement of these objects to follow 开发者_开发问答a users finger?

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There is no built-in support of dragging controls and you need to implement one. My answer to another question is related and might help.

Dragging values onto labels