Q.What do you mean by directing manipulation and indirect manipulation? (5 M) (DEC 16 /MAY 16 /DEC 17)
Ans:-
Direct manipulation:-
- Definition:- Direct manipulation (DM) is an interaction style in which users act on displayed objects of interest using physical, incremental, reversible actions whose effects are immediately visible on the screen.
- Example:
- dragging a document to the trash
- changing the size of a triangle by interacting with a visual representation of a triangle
- inserting characters in a document by pointing to where they should go (with a mouse/cursor/insertion point) and then typing
- “dialing” a phone number by pushing numbers on a keypad
- playing a song using controls like a physical tape deck or CD/DVD player
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| Moving a file on MacOS using direct manipulation involves dragging that file from the source folder and moving it into the destination folder. |
- Characteristics:
- The task objects are manipulated by physical actions, such as clicking or dragging, rather than by entering complex syntax.
- There is a visible and continuous representation of the task objects and their actions. Consequently, there is little syntax to remember.
- Rapid learning
- Their effects on task objects are immediately visible.
- Reversibility of (almost) all actions
- Users can explore without severe consequences
- Syntactic correctness
- every operation is legal
- Disadvantages:
- DM is slow
- Repetitive tasks are not well supported.
- Some gestures can be more error-prone than typing
- Accessibility may suffer
Indirect manipulation:-
- Indirect manipulation substitutes words and text, such as pull-down or pop-up menus, for symbols, and substitutes typing for pointing.
- Most windows system are a combination of both direct and indirect manipulation
- Example:
- A menu ma be accessed by pointing at a menu icon and then selecting it( direct manipulation)
- The menu itself, however, is a textual list of operations (Indirect manipulation)
- When an operation is selected from the list, by pointing or typing the system executes it as a command
- Disadvantages:
- The operation may be difficult to conceptualize
- Graphics capability limited
- Amount of space available for placing manipulation controls in the window border may be limited.
- Difficult to remember all the necessary operations
