The document discusses an optimistic approach to updating the user interface in mobile applications. It proposes showing predicted results to users immediately instead of loading spinners to improve perceived performance. This involves caching data, preloading content, and updating the UI with fake results before the server response arrives. It can improve the user experience but requires handling errors if the prediction does not match the actual response. The approach also needs to account for frequent actions from hyperactive users.

1. Optimistic Approach
How to show results instead spinners
without breaking your Application
by Paul Taykalo, Stanfy
Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 1

2. Optimistic Approach
What is it about?
Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 2

3. Optimistic Approach
4 Speeding up application
4 "Speeding" up application
4 Making user happier
4 It's all about user-friendliness
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4. How mobile application works
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5. How mobile application works
4 Handle user action
4 Send request to the server
4 Get response from the server
4 Update UI
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6. Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 6

7. User need to wait
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8. User need to wait
But user don't like to wait
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9. User need to wait
But user don't like to wait
User don't have time to wait
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10. Loading next slide
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11. Solutions?
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12. Solutions - Making app faster
4 Decrease sizes
4 Compression
4 Opened connection to the server
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13. Solutions - One step
ahead
4 Caching
4 Preload pages
4 Load content in the backround
4 Be prepared
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14. Solutions - Entertain user
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15. Solutions - Entertain the user
4 Animations
4 Push/Pop
4 Spinner
4 Progress
4 Skeleton
4 Partial info
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16. Solutions - Predict
the result
4 Precalculate result
4 Show it to user
4 ????
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17. Solutions - Predict
the result
4 Precalculate result
4 Show it to user
4 Pray :)
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18. Types of user
interactions
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19. Actions
and
Expectations
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20. Actions and Expectations
4 If I press like I expect that
4 If I edit post I expect that
4 If I follow this guy I expect that
4 If I open a post I expect that
4 If I ask for a radom number I expect that
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21. Predictabevs
*elbatciderpnU_
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22. Predictable
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23. Predictable
If I can predict the result, why should I wait for
confirmation?
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24. Optimistic models
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25. Non optimistic model
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26. Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 26

27. Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 27

28. Following a person
[self.requestManager follow:original result:^(Person *res, NSError *err) {
if (err) {
// Handling error
resultBlock(nik, err);
} else {
// Updating to the new value
resultBlock(res, nil);
}
}];
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29. Following a person
// Saving original for later usage
Person *original = self.person;
// Create fake result
Person *fake = [self.person copy];
fake.followingStatus = @"Following";
// Updating current object
self.person = fake;
resultBlock(fake, nil);
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30. Following a person
if (error) {
// rollback
weakSelf.person = original;
resultBlock(original, error);
} else {
// Updating to the new value
weakSelf.person = updatedPerson;
resultBlock(updatedPerson, nil);
}
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31. Following a person
// Following a person
- (void)follow:(void (^)(Person *person, NSError *error))resultBlock {
__weak __typeof(self) weakSelf = self;
// Saving original for later usage
Person *original = self.person;
// Create fake result
Person *fake = [self.person copy];
fake.followingStatus = @"Following";
// Updating current object
self.person = fake;
resultBlock(fake, nil);
// Calling request manager
[self.requestManager followPerson:original result:^(Person *updatedPerson, NSError *error) {
if (error) {
// rollback
weakSelf.person = original;
resultBlock(original, error);
} else {
// Updating to the new value
weakSelf.person = updatedPerson;
resultBlock(updatedPerson, nil);
}
}];
}
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32. What about non-breaking?
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33. Correct View Layer
MVVM*
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34. Correct View Layer
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35. Correct View Layer
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36. Hiperactive User?
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37. Hiperactive User?
like unlike like unlike like unlike like unlike
like unlike like unlike like unlike like unlike
like unlike like unlike like unlike like unlike
like unlike like unlike like unlike like unlike
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38. State based on multiple updates
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39. State based on multiple updates
Take a look at Parse SDK
PFObjectEstimatedData.h
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40. Demo?Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 40

41. Recap
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42. Recap
4 It's pretty easy to trick user
4 Show user what he expect
4 Fight for your users, they deserve it
4 Now you can write even cooler apps :)
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43. Last slide :)
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44. Optimistic Approach
How to show results instead spinners
without breaking your Application
by Paul Taykalo, Stanfy
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45. Links
4 http://www.reactnative.com/
4 https://speakerdeck.com/frantic/react-native-
under-the-hood
4 https://medium.com/stanfy-engineering-practices/
do-not-let-your-user-see-spinners-35b824c3ce2f
4 ComponentKit
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46. Paul Taykalo, Optimistic Approach : How to show results instead spinners without breaking your Application, Stanfy, 2015 46