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ViewAssertion

interface ViewAssertion

Responsible for performing assertions on a View element.

This is considered part of the test framework public API - developers are free to write their own assertions as long as they meet the following requirements:

Do not mutate the passed in view.
Throw junit.framework.AssertionError when the view assertion does not hold.
Implementation runs on the UI thread - so it should not do any blocking operations
Downcasting the view to a specific type is allowed, provided there is a test that view is an instance of that type before downcasting. If not, an AssertionError should be thrown.
It is encouraged to access non-mutating methods on the view to perform assertion.

Strongly consider using a existing ViewAssertion via the ViewAssertions utility class before writing your own assertion.

Summary

Public methods
`abstract void`	`check(View view, NoMatchingViewException noViewFoundException)` Checks the state of the given view (if such a view is present).

Public methods

check

abstract void check(View view, NoMatchingViewException noViewFoundException)

Checks the state of the given view (if such a view is present).

Parameters
`View view`	the view, if one was found during the view interaction or null if it was not (which may be an acceptable option for an assertion)
`NoMatchingViewException noViewFoundException`	an exception detailing why the view could not be found or null if the view was found