The search dialog is a user interface component that is controlled by the Android system. When activated by the user, a search dialog box appears at the top of the action.
A search widget is an instance of SearchView that can be placed anywhere in your layout. By default, the search widget behaves like a standard EditText widget and does nothing, but you can configure it so that the Android system processes all input events, delivers requests for the appropriate action and provides search suggestions.
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