Add possibility to calculate screenshots overlap score + several helpers

[mykola-mokhnach]

Change list

This feature has been asked by several users, so I've just nicely decorated the code we use in our own automation framework and added it to the client.

Types of changes

• No changes in production code.
• Bugfix (non-breaking change which fixes an issue)
• [ x ] New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Details

Screenshots comparison algorithm itself is based on standard opencv calls. That is why the library has been added to Gradle config as a dependency.

[jsf-clabot]

All committers have signed the CLA.

[mykola-mokhnach]

@TikhomirovSergey is checkstyle configured properly here?

The tool does not like how one decorates loops with post-condition:

do {
....
} while (System.currentTimeMillis() - started <= timeoutMs);

The output is

[ant:checkstyle] [ERROR] /home/travis/build/appium/java-client/src/main/java/io/appium/java_client/ScreenshotState.java:165:9: '}' at column 9 should be alone on a line. [RightCurly]

Somebody should be wrong here...

[SrinivasanTarget]

The tool does not like how one decorates loops with post-condition:

We follow Google's standards :)

[SrinivasanTarget]

@mykola-mokhnach Can you rebase this branch as well with master to make commits clean?

[mykola-mokhnach]

@SrinivasanTarget squashing done. Waiting for review comments.

[mykola-mokhnach]

@SrinivasanTarget@saikrishna321 could you please find some time to finish the review?

[SrinivasanTarget]

Will review it soon

…

On Fri 17 Mar, 2017, 2:04 PM Mykola Mokhnach, ***@***.***> wrote: @SrinivasanTarget <https://github.com/SrinivasanTarget> @saikrishna321 <https://github.com/saikrishna321> could you please find some time to finish the review? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#595 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AIfAJc7aNfMYsjVmT97GnOj6wvqzSIFMks5rmkWKgaJpZM4MYltd> .

[TikhomirovSergey]

@mykola-mokhnach I remember about this PR. It is the next for the revieving.

[TikhomirovSergey]

@mykola-mokhnach
Hi. Sorry for the delaying.

There are some issues.
I can't run it from IDE (IntellijIDEA 2017.1) nor via command line.

IDEA

Command line

What is wrong?

[TikhomirovSergey]

@mykola-mokhnach
Also there is the question. I think the scope of this feature is more general than mobile automation. Why is it necessary to include it to appium java client?

[mykola-mokhnach]

Hi @TikhomirovSergey
It was failing because of inconsistent opencv lib import. This was one of cases when it "works for me". Now the problem should be fixed and all the unit tests were double checked as well.

[mykola-mokhnach]

Regarding why it is necessary for java lib - several users were asking for it. And we also have similar implementation in our own automation framework. So I just wanted to share verified solution and give people possibility to solve more problems with Appium (since the java client is the most popular one).

[TikhomirovSergey]

@mykola-mokhnach
ok
Yeah. All tests are green now.