anyone know if theres a way to pass args into the ...
# androidv
Vincent Williams
08/14/2020, 5:42 PManyone know if theres a way to pass args into the constructor of a fragment using the navigation component? I have a VehicleFragment that should take a vin. I know I can pass it in via a bundle but was wondering if constructor args are possible with the nav component
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Ian Lake
08/14/2020, 5:45 PMArguments are for things that change from one instance to the next, so that is absolutely what you should be using for something like a vin - you might look at Safe Args for how to make that type safe with Navigation: https://developer.android.com/guide/navigation/navigation-pass-data#Safe-args
Ian Lake
08/14/2020, 5:46 PMThat being said, Navigation does support
FragmengFactoryv
Vincent Williams
08/14/2020, 5:46 PMyes I know about safeArgs, I just wasnt sure if there was a way to pass in via the constructor
Vincent Williams
08/14/2020, 5:47 PMSafeArgs is somewhat messy because it generates all those Directions for every navigation action
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Ian Lake
08/14/2020, 6:10 PMI mean, yes, that's what you should be using to navigate all the time
Ian Lake
08/14/2020, 6:10 PMIf you aren't using that action, then delete the action
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Vincent Williams
08/14/2020, 6:11 PMI disagree. I think avoiding code generation has a lot of benefits
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Ian Lake
08/14/2020, 6:12 PMI'm confused. In what cases would code be generated that you wouldn't actually be using?
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Vincent Williams
08/14/2020, 6:13 PMIm not saying you wouldnt use the generated code, but the generated code could be avoided by using bundles and I think in general across all libraries there is benefit to avoiding code generation
Vincent Williams
08/14/2020, 6:14 PMits a tradeoff but the benefit in this particular case is not worth it imo but it might be worth it for others depending on their project and use case
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Ian Lake
08/14/2020, 6:15 PMSure, that's why Safe Args is optional. You can certainly skip any sense of type safety and manually build and parse bundles and keep that code in sync without any help from the compiler.
Ian Lake
08/14/2020, 6:15 PMI don't know why anyone would put themselves through that, but YMMV. Most of the code gets stripped away from R8 anyways
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Vincent Williams
08/14/2020, 6:16 PMmore concerned about build time. I would rather take the upfront time to write the bundle code (honestly not hard and what has been done for years prior to safeargs) than the build time cost on every single build
Vincent Williams
08/14/2020, 6:17 PMsame reason im not a huge fan of dagger
Vincent Williams
08/14/2020, 6:17 PMthe more code generation you can avoid the faster build and iteration time
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Ian Lake
08/14/2020, 6:17 PMIt is fully incremental, only recompiling when your navigation graph file changes
Ian Lake
08/14/2020, 6:18 PMSo...maybe try it first and measure the impact
Ian Lake
08/14/2020, 6:22 PMIf you find a case where it isn't incremental at the navigation graph file level, please do file a bug: https://issuetracker.google.com/issues/new?component=409828&template=1093757