For each step of the user's operation, the system must provide timely feedback.
Four Principles of Interaction Design
For any user operation on the interface, whether it is click, scroll or double-click, the system should give timely feedback, including display changes and result feedback.
Display changes: Display changes are feedback to the user's mouse events, gesture operations, or focus events. After the user triggers these events, the system must have display changes.
For example, if the focus is within the input box, the color of the input box will change; if the focus moves out of the input box, the color of the input box will also change. For another example, if the mouse hovers over the confirmation button, the color of the button will change.
The system lets the user know that the operation is valid through changes in the display. It is naturally good that the display changes after the user's operation, so the display change can be used a lot.
Result feedback: After the user inputs the information, the system should give the user feedback on the result. This result can be an error, failure or success, etc. There are two points to consider when giving feedback on results, namely after inputting and after submitting.
1 completed case
After the user enters the mobile phone number and moves the focus, the system prompts the user that the mobile phone number is incorrect; when the user enters the login name and moves the focus, the system prompts that the number of login names is insufficient.
2Submitted cases
When the user clicks the button, the system prompts that the login is successful and jumps to the next page.
Unlike display changes, result feedback is only used occasionally, and using it too much is not good. On the one hand, it is difficult for developers to implement it. On the other hand, the system should not have too much result feedback before the user completes the operation.
The Four Principles of Interaction Design
Two error-proofing principles
Prevent users from making mistakes before they happen.
Good design avoids errors before they happen, rather than telling users they are wrong and asking them to redo them after they happen. The error-proof method has friendly prompts and forbidden errors.
1 Friendly Tips
Give users clear prompts to avoid user errors.
For example, when the user fills in the mobile phone number, the system can display the mobile phone number in segments in the "3-4-4" format.
2 forbidden errors
Friendly prompts can only prompt errors. A better way is to prevent users from making errors and not create opportunities for errors. The way to prohibit errors is to prevent users from filling in the wrong information, or the system automatically ignores it after filling in the wrong information.
a case where users are not allowed to fill in mistakes
When the user fills in the mobile phone number, the system must prohibit the user from filling in non-numeric characters, and the input of more than 11 digits is not allowed.
The number 1 or the letter I is prohibited from appearing in the verification code
b The system automatically ignores the case after filling in the wrong
When users download network disk files, they need to enter a verification code. When users paste the verification code, they sometimes paste spaces in. In this case, the system should ignore the spaces.
Three withdrawal principles
Provides the ability to undo after an error occurs.
Users will enter the wrong information, or touch the wrong function. After these errors, the interface should support undo and redo.
For example, adding a delete button next to an input field or adding an undo action after sending a message.
Four principles of fault tolerance
Point out errors and give suggestions to reduce user losses.
The undo principle emphasizes undoing the user's operation, while the fault tolerance principle emphasizes how the system should respond when the user has completed the task and an error has occurred. There are two methods: pointing out mistakes and reducing losses.
1Point out the error
The user wants to register a new email address, but the email address has already been registered. At this time, the system will prompt "The email address has been registered" and give suggestions.
2 Reduce losses
The user wants to delete photos in batches, which is a dangerous operation. At this time, the system must fulfill its obligation to remind that the photos will be deleted. If the user still insists on deleting, this may lead to an error. At this time, the system should provide a recycle bin to give the user a chance to regret.
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