[google_maps_flutter] Widget based polyline support for google maps.

[awazgyawali]

PR to support polyline on both Android and IOS.

UPDATE: Mar 9, 2019

This PR initially was a controller based support. As the flutter team has added widget based marker support, so I also added the same widget based support for the polyline.

If you want to use controller-based polyline support use the following

 google_maps_flutter: 
    git:
      url: git://github.com/awazgyawali/plugins/
      path: packages/google_maps_flutter
      ref: cd06409

and if you want to use the widget based solution use the following.

  google_maps_flutter:
      git:
        url: git://github.com/awazgyawali/plugins/
        path: packages/google_maps_flutter
        ref: google_maps_polyline

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[awazgyawali]

@irevans Can you sign the CLA agreement anytime soon? I think you were about to confirm it from your employer.

[ZatacaSystems]

@irevans Can you sign the CLA agreement anytime soon? I think you were about to confirm it from your employer.

@irevans Any news about this?

[irevans]

@awazgyawali I'm still waiting on my employer to sign the cla, it's shouldn't take much longer, I'm chasing it up regularly.

When you added the iOS support I was wondering whether you took a look at the flutter code. I'm interested in whether you think using null to represent the default pattern in the PolylineOptions class is a good idea. Perhaps using an empty list would be better, such that null is used to consistently mean "do not change this configuration option".

[awazgyawali]

Never noticed that coz IOS sdk for google maps doesn't seem to have support for patterns out of the box nor start cap and end cap, so I didn't look at the pattern code.

However I found this “Dotted Polylines with Google Maps SDK for iOS” by Dylan Maryk https://link.medium.com/bjo68I3AwT just now.

I might have to look at this and your work to implement pattern for android to check if they match or not.

[irevans]

@awazgyawali I'm going to running the iOS version of the sample application. Where is the google maps API KEY specified on the iOS side?

[iskakaushik]

@awazgyawali looks like some of the functionality is still missing on the iOS side, caps, joints etc. Do you plan on adding it?

[awazgyawali]

@iskakaushik I am aware of the missing features. I was planning to cap feature on IOS but haven't found a way to actually change the cap. Also for the joints, the SDKs seems to provide different kind of methods on the IOS side. Not sure how we should use them.

On android it has PatternItem but on IOS it has Spans. I think we can use spans too to make the gap behavior work by using transparent color. IOS documentation for spans are here.

[iskakaushik]

@awazgyawali ah, i see. I made the example more obvious to account for that. I also added some dart doc on the fields that are currently supported on Android only. We can add some version of translation from patterns to spans on iOS. I do not think that should block this PR.

[googlebot]

A Googler has manually verified that the CLAs look good.

(Googler, please make sure the reason for overriding the CLA status is clearly documented in these comments.)

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[iskakaushik]

For CLA, i've manually verified that the only committers are:

Author: Aawaz Gyawali <awazgyawali@gmail.com>
Author: EVANS, Ian 3 <Ian.Evans3@admiralgroup.co.uk>
Author: Ian Evans <ian.evans3@admiralgroup.co.uk>
Author: Kaushik Iska <kaushikiska@google.com>

My suspicion is that the bot is not case insensitive. Overriding the CLA check.

[googlebot]

So there's good news and bad news.

👍 The good news is that everyone that needs to sign a CLA (the pull request submitter and all commit authors) have done so. Everything is all good there.

😕 The bad news is that it appears that one or more commits were authored or co-authored by someone other than the pull request submitter. We need to confirm that all authors are ok with their commits being contributed to this project. Please have them confirm that here in the pull request.

Note to project maintainer: This is a terminal state, meaning the cla/google commit status will not change from this state. It's up to you to confirm consent of all the commit author(s), set the cla label to yes (if enabled on your project), and then merge this pull request when appropriate.

ℹ️ Googlers: Go here for more info.

[googlebot]

A Googler has manually verified that the CLAs look good.

(Googler, please make sure the reason for overriding the CLA status is clearly documented in these comments.)

ℹ️ Googlers: Go here for more info.

[irevans]

@iskakaushik would I be right in thinking that only the user that opened the PR gets contribution credit for this work?

[iskakaushik]

@irevans , i'm not sure what you mean by contribution credit. I will check with my team and let you know. If there is some explicit credit, i'll make sure that you get it as well.

[irevans]

@iskakaushik I was referring to githubs recognition that a user is a contributor to a project. I found this in GitHub's documentation here:

"When a pull request is merged and commits are squashed, only the user that merged the pull request and the user that opened the pull request receive contribution credit. No other contributors to the pull request will receive contribution credit."

In which case I'm guessing there is nothing you can do about that. Thanks in any case.

[stevenspiel]

@awazgyawali Have you given thought to Polygon support? Do you think they could coexist? Structurally, what makes the most sense to you?

• An abstract Polyshape class that Polyline and Polygon both implement
• A Polyshape object with an enclosed bool option (polygons would also need a fillColor param)
• Handle them separately by duplicating Polyline code and adjusting where needed to allow for polygon support

I'd love to know your thoughts on it.

[thiagotalma]

Is it possible to use an encoded string as a path?
(https://developers.google.com/maps/documentation/utilities/polylinealgorithm)

[debkanchan]

Is it possible to use an encoded string as a path?
(https://developers.google.com/maps/documentation/utilities/polylinealgorithm)

Yes, you just need to have a decoder function. I have one because I use the directions api to do exactly this. let me put it up on a gist.

Edit: here it is https://gist.github.com/DebkanchanSamadder/b428e052279b7124b8edb974536f47f9

[SDRuiz]

Can I ask some questions regarding the google_maps_flutter polylines? because in the flutter-dev groups noone answer.
Thanks!

Q: https://groups.google.com/forum/#!topic/flutter-dev/QX4CKNKQOrw