Android – SearchView: Adding a Search component direct on your APP menu.

 

A SearchView is View (GUI Component) to be displayed in the toolbar, which user can enter a text for searching anything within your APP.

Of course, programmatically we can Interact with SeachView to identify the its interaction with the user and the inputted values. However the whole search behavior has to be implemented by each application.

 

 

In this tutorial we are going to see how to include a SearchView in your APP toolbar, and how to handle its events.

 

 

The SearchView is defined in any layout for menus, and its is like a normal menu item. However it has different behavior because of the attributes  app:actionViewClass and app:showAsAction as we can see in the code below:

 

<?xml version="1.0" encoding="utf-8"?>

<menu xmlns:app="http://schemas.android.com/apk/res-auto"

    xmlns:android="http://schemas.android.com/apk/res/android">



    <item

        android:id="@+id/app_bar_search"

        android:icon="@drawable/ic_search_black_24dp"

        android:title="Search"

        app:actionViewClass="android.widget.SearchView"

        app:showAsAction="always|collapseActionView" />
</menu>

 

 

Then in the Activity we want to employ this menu, in the method onCreateOptionsMenu it is necessary to instantiate and assign a SearchView.OnQueryTextListener object, because this object that will introduce a custom behavior to this View object, otherwise, it will be just a inanimate element in user interface.

 

 

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main_menu, menu);

    // Associate searchable configuration with the SearchView
    SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    SearchView searchView = (SearchView) menu.findItem(R.id.app_bar_search).getActionView();
    searchView.setSearchableInfo( searchManager.getSearchableInfo(getComponentName()));
    final SearchView.OnQueryTextListener queryTextListener = new SearchView.OnQueryTextListener() {
        @Override
        public boolean onQueryTextChange(String newText) {
            ((TextView)findViewById(R.id.textViewSearchViewText)).setText(newText);
            return true;
        }
        @Override
        public boolean onQueryTextSubmit(String query) {
            ((TextView)findViewById(R.id.textViewSearchViewText)).setText(query.toUpperCase());
            return true;
        }
    };


    searchView.setOnQueryTextListener(queryTextListener);
    return true;
}

 

Here there is two important methods to be overwritten, the onQueryTextChange which is going to be triggered every inputted char, and the onQueryTextSubmit that will be triggered just When user concludes its typing, normally pressing the Lupe button. Depending of what are you developing you can choose to introduce behavior to both methods or just a single one.

 

You can watch a video class about this topic below:



 

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