java.lang.NullPointerException: Expected to find a PathContext but did not. about flow HOT 9 CLOSED

I did another experiment : I added a loging command to the commented line :
if (context.getSystemService("PATH_CONTEXT") == null) {
L.info("not a path context $context ${(context as? ContextWrapper)?.getBaseContext()}")
throw Exception("not a path context $context ${(context as? ContextWrapper)?.getBaseContext()}")
}

And I got interesting results :

1. getContext() of both views are actualy NOT wrapped with a PathContext (the 2 lines appeared in logcat)
2. adding an exception with the commented line must have trigger a catch block somewhere that swallows my exception and that makes the code work (bad luck, I was hoping to find where the problem was coming from that way)

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Another experiment with print debug statements.
It looks like the error comes from this part of the code :
val context = PathContext.create(oldPath, to, contextFactory)
val layout = getLayout(to)
val newView = LayoutInflater.from(context).cloneInContext(context).inflate(layout, containerView, false)

My print statements tell me that context is able to deliver a PathContext but not newView.getContext()
Which is weird as I guess that the cloneInContext part was all about using a layoutInflater set with the good PathContexted context...
Let's now grep LayoutInflater

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I looked into the chains of ContextWrapper.
newView.getContext() has :
org.lakedaemon.android.flow.MyFlowActivity@427b02c8
android.app.ContextImpl@42807fe0

context has :
flow.path.PathContext@428fc308
flow.path.Path$LocalPathWrapper@428fc2c8
org.lakedaemon.android.flow.MyFlowActivity@427b02c8
...

Also I checked LayoutInflater.from(context).cloneInContext(context)
the Context it holds is identityEquals to context
So the issue certainly comes from inflate(layout, containerView, false)

When I grepped the LayoutInflater code, it seemed to me that there might be a possibility the context could be changed (when a view uses a theme...)

from flow.

@Lakedaemon Do you use AppCompatActivity from 22.1.+? If so, there is a know issues with misusing context during inflation (see workaround inside): #88 (dig into mortar issue)

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Yes I'm using AppCompatActivity (to get support for the api range 9 to 22) and I believe that I suffer from this exact issue. Thanks for the pointer.

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To fix this, just use LayoutInflater.from(context.getApplication()).cloneInContext(context).inflate(...)

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And you also need to initialize your container view group like this

PathContext pathContext = PathContext.root(this);
    framePathContainerView = (MortarScreenSwitcherFrame) LayoutInflater.from(this)
            .cloneInContext(pathContext)
            .inflate(R.layout.activity_main, null);
setContentView(framePathContainerView);

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Thanks for the tip. It really helped.

from flow.

See also #91

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