How Android gets the LayoutInflater object

When writing Android programs, you may sometimes write custom views and use the Inflater object to parse the layout file into a View. This article aims to summarize the methods for obtaining LayoutInflater objects.

1. If you can obtain the context object, you can use the following methods:

LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);View child = inflater.inflate(R.layout.child, null);

Or

LayoutInflater inflater = LayoutInflater.from(context);View child = inflater.inflate(R.layout.child, null);

2. In an Activity, you can use the following methods:

View child = getLayoutInflater().inflate(R.layout.child, item, false);

Or

View view; LayoutInflater inflater = (LayoutInflater)   getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(R.layout.mylayout, null);

Both method 1 and method 2 actually use context (). getSystemService ().

3. static View method:

View view=View.inflate(context, R.layout.child, null)

The source code of inflate is as follows:

    /**     * Inflate a view from an XML resource.  This convenience method wraps the {@link     * LayoutInflater} class, which provides a full range of options for view inflation.     *     * @param context The Context object for your activity or application.     * @param resource The resource ID to inflate     * @param root A view group that will be the parent.  Used to properly inflate the     * layout_* parameters.     * @see LayoutInflater     */    public static View inflate(Context context, int resource, ViewGroup root) {        LayoutInflater factory = LayoutInflater.from(context);        return factory.inflate(resource, root);    }

LayoutInflater. from (context) is actually packaging method 1. You can refer to the following source code:

    /**     * Obtains the LayoutInflater from the given context.     */    public static LayoutInflater from(Context context) {        LayoutInflater LayoutInflater =                (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);        if (LayoutInflater == null) {            throw new AssertionError("LayoutInflater not found.");        }        return LayoutInflater;    }