[TIMOB-9403] Add centerOffset-property handling for Android map annotations.

[ndob]

This pull request adds handling for centerOffset-property on Map.Annotation-objects.
Relevant JIRA-ticket: https://jira.appcelerator.org/browse/TIMOB-9403

This should work as the corresponding iOS-feature: offset is in pixels, positive values move down and right. [1]

Only open issue is, that when centerOffset-property is not set, Android uses the default anchor, which points to horizontal center and vertical bottom [2]. I didn't dare to break the existing functionality by defaulting to horizontal and vertical center, but comments regarding to this are of course welcome.

[1] https://developer.apple.com/library/ios/documentation/MapKit/Reference/MKAnnotationView_Class/index.html#//apple_ref/occ/instp/MKAnnotationView/centerOffset
[2] https://developer.android.com/reference/com/google/android/gms/maps/model/Marker.html

[ndob]

Is it possible to get this merged?

[jonatansberg]

@ndob Thank you for implementing this, you just saved the better part of my day! :)

A small heads up though: with the current implementation the centerOffset point needs to be set in system units, even if you use another unit (e.g. dips) as the default unit.

[ingo]

Can you please add documentation to https://github.com/appcelerator-modules/ti.map/blob/master/apidoc/Annotation.yml#L61?

[ndob]

@mrlundis Great to hear. :) The offset is currently in pixels, because in iOS documentation (link number 1) it says: "This x and y offset values are measured in pixels.". So this should be in parity with that.

@ingo I added Android-platform to the documentation now.

[ndob]

Is there something preventing the merge of this PR?

[yozef]

I've actually reimplemented your code in my version of Ti.Map for Android, and it does the job.

[williamrijksen]

@ingo Can you take a look at this PR? I resolved the merge conflicts about this PR. The errors occurring in Travis, but i don't know the exact reason.

[williamrijksen]

Ready for review!

[ashcoding]

@williamrijksen I'll be happy to review this. Travis seems to be passing.

[ashcoding]

@williamrijksen could you write a sample app/test for the PR? That would help greatly.

Also could you rebase this branch? We just merged a commit and this seems to have made ur branch to be in conflict.

[williamrijksen]

@ashcoding merge conflict solved

[williamrijksen]

@ashcoding Because you asked my to write a sample app, i wrote that one. You can find it here: https://github.com/williamrijksen/TiMapsSample. It's still necessary to set you own Google maps-key to do a functional test.

To clarify what is happening I'll insert two screenshots. One with a default annotation and one with a set centerOffset property.

1. Default
   
2. With centerOffset: {x:0,y:0}
   

If you have any questions, don't hesitate to ask them.

[williamrijksen]

@ashcoding See the difference:

1. Default: https://github.com/williamrijksen/TiMapsSample/blob/master/app/controllers/defaultMap.js#L6.
2. With Centeroffset: https://github.com/williamrijksen/TiMapsSample/blob/master/app/controllers/centerOffsetMap.js#L9.

[ashcoding]

@williamrijksen would handling offset changes in the onPropertyChanged https://github.com/appcelerator-modules/ti.map/pull/79/files#diff-f3c99af2a7979e334ec513288183b11cR318 be required as well?

[williamrijksen]

@ashcoding I tried to handle the offset changes in the propertyChanged, but the view didn't update. I think it's the same issue as https://jira.appcelerator.org/browse/TIMOB-19543.

[ashcoding]

@williamrijksen Okay. Understand where you're coming from. :)

[jvandijk]

@ashcoding @hansemannn please have a look at this PR again. I've just updated the merged master into it to make it completely in sync again.
We are already using this in production quite a while.

[hansemannn]

LGTM. @ashcoding has the final decision here.

[ashcoding]

It looks good but I'm having trouble making the offset work. I'm getting both images look like the default.

@hansemannn are you able to functionally test it out?

[williamrijksen]

@ashcoding @hansemannn What's the state of this PR?

[jvandijk]

@ashcoding see this example code as @williamrijksen provided: https://github.com/williamrijksen/TiMapsSample/blob/master/app/controllers/centerOffsetMap.js#L6

[ashcoding]

Tried it again. Works. I think I did something wrong earlier. In any case, works well. 👍

[ashcoding]

Code reviewed and functionally tested.
Approved