Command mode in Design Mode

To be continued, the update is expected to be completed at 10.28.

1 concept

The client sends one or more commands or requests without worrying about who the receiver is and how to implement it.

2. Applicable scenarios and advantages and disadvantages

Applicable scenarios: the client needs to send different commands at different times; the client and receiver need to be decoupled; the system needs to support the Undo redo operation.

Advantage: strong scalability, easy to combine commands.

3 Interpretation of command mode

Abstract commands

Specific commands: receive recipient commands

Receiver: Detailed Implementation

Caller: holding the command object

Client: create a specific command and set the receiver for the command.

4. Implementation example

 

Command mode in Design Mode