|
|
|
|
|
|
|
Graphically, the following diagram illustrates how various model–view class instances fit together.
Application
*------------*
Creates and connects | |
*-----------------*--------*----------------*-----| |
| | | | | |
| | | | *------------*
v | v |
Model | Observer | View
*------------* *------------* | *------------*
| | Activates | | *---> | |
| | ----------> | | | |
| | Fetch | | | |
| *-------------- | | | |
| | | *------------* | |
| | | Relay | |
| *----------------------------------------> | |
| | | |
| | | Listener | |
| | | *------------* | |
| | *--> | | Activates | |
| | | | <---------- | |
| | | | Fetch | |
| | | | --------------* |
| | *------------* | | |
| | Relay | | |
| | <----------------------------------------* |
| | | |
*------------* *------------*
The diagram treats the instances anthropomorphically, using words such as connect, activate, fetch, and relay. Later, you learn how to translate those words into calls to particular methods.