zhangge's stupid and messy life

LayoutInflater.from(context).inflate(R.layout.activity_main_list_item, null);

LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

/**
 * Use with {@link #getSystemService} to retrieve a
 * {@link android.view.LayoutInflater} for inflating layout resources in this
 * context.
 *
 * @see #getSystemService
 * @see android.view.LayoutInflater
 */
public static final String LAYOUT_INFLATER_SERVICE = "layout_inflater";

LayoutInflater inflater = LayoutInflater.from(context);

/**
 * 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;
}

LayoutInflater inflater = Activity.getLayoutInflater();

/**
 * Convenience for calling
 * {@link android.view.Window#getLayoutInflater}.
 */
@NonNull
public LayoutInflater getLayoutInflater() {
    return getWindow().getLayoutInflater();
}

public PhoneWindow(Context context) {
    super(context);
    mLayoutInflater = LayoutInflater.from(context);
}

View.inflate(context, R.layout.view_layout, null);

/**
 * 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);
}

public Object getSystemService(String name) {
    if (LAYOUT_INFLATER_SERVICE.equals(name)) {
        if (mInflater == null) {
            mInflater = LayoutInflater.from(getBaseContext()).cloneInContext(this);
        }
        return mInflater;
    }
    return getBaseContext().getSystemService(name);
}

/**
 * @return the base context as set by the constructor or setBaseContext
 */
public Context getBaseContext() {
    return mBase;
}

public ContextWrapper(Context base) {
    mBase = base;
}

/**
 * Create a copy of the existing LayoutInflater object, with the copy
 * pointing to a different Context than the original.  This is used by
 * {@link ContextThemeWrapper} to create a new LayoutInflater to go along
 * with the new Context theme.
 * 
 * @param newContext The new Context to associate with the new LayoutInflater.
 * May be the same as the original Context if desired.
 * 
 * @return Returns a brand spanking new LayoutInflater object associated with
 * the given Context.
 */
public abstract LayoutInflater cloneInContext(Context newContext);

/**
 * Instantiates a layout XML file into its corresponding {@link android.view.View}
 * objects. It is never used directly. Instead, use
 * {@link android.app.Activity#getLayoutInflater()} or
 * {@link Context#getSystemService} to retrieve a standard LayoutInflater instance
 * that is already hooked up to the current context and correctly configured
 * for the device you are running on.  For example:
 *
 * <pre>LayoutInflater inflater = (LayoutInflater)context.getSystemService
 *      (Context.LAYOUT_INFLATER_SERVICE);</pre>
 * 
 * <p>
 * To create a new LayoutInflater with an additional {@link Factory} for your
 * own views, you can use {@link #cloneInContext} to clone an existing
 * ViewFactory, and then call {@link #setFactory} on it to include your
 * Factory.
 * 
 * <p>
 * For performance reasons, view inflation relies heavily on pre-processing of
 * XML files that is done at build time. Therefore, it is not currently possible
 * to use LayoutInflater with an XmlPullParser over a plain XML file at runtime;
 * it only works with an XmlPullParser returned from a compiled resource
 * (R.<em>something</em> file.)
 * 
 * @see Context#getSystemService
 */

/**
 * Inflate a new view hierarchy from the specified xml resource. Throws
 * {@link InflateException} if there is an error.
 * 
 * @param resource ID for an XML layout resource to load (e.g.,
 *        <code>R.layout.main_page</code>)
 * @param root Optional view to be the parent of the generated hierarchy.
 * @return The root View of the inflated hierarchy. If root was supplied,
 *         this is the root View; otherwise it is the root of the inflated
 *         XML file.
 */
public View inflate(int resource, ViewGroup root) {
    return inflate(resource, root, root != null);
}

/**
 * Inflate a new view hierarchy from the specified xml resource. Throws
 * {@link InflateException} if there is an error.
 * 
 * @param resource ID for an XML layout resource to load (e.g.,
 *        <code>R.layout.main_page</code>)
 * @param root Optional view to be the parent of the generated hierarchy (if
 *        <em>attachToRoot</em> is true), or else simply an object that
 *        provides a set of LayoutParams values for root of the returned
 *        hierarchy (if <em>attachToRoot</em> is false.)
 * @param attachToRoot Whether the inflated hierarchy should be attached to
 *        the root parameter? If false, root is only used to create the
 *        correct subclass of LayoutParams for the root view in the XML.
 * @return The root View of the inflated hierarchy. If root was supplied and
 *         attachToRoot is true, this is root; otherwise it is the root of
 *         the inflated XML file.
 */
public View inflate(int resource, ViewGroup root, boolean attachToRoot) {
    final Resources res = getContext().getResources();
    if (DEBUG) {
        Log.d(TAG, "INFLATING from resource: \"" + res.getResourceName(resource) + "\" ("
                + Integer.toHexString(resource) + ")");
    }

    final XmlResourceParser parser = res.getLayout(resource);
    try {
        return inflate(parser, root, attachToRoot);
    } finally {
        parser.close();
    }
}

public View inflate(XmlPullParser parser, ViewGroup root) {
    return inflate(parser, root, root != null);
}

public View inflate(XmlPullParser parser, ViewGroup root, boolean attachToRoot) {
//...
}

public View inflate(XmlPullParser parser, ViewGroup root, boolean attachToRoot) {
    synchronized (mConstructorArgs) {
        final AttributeSet attrs = Xml.asAttributeSet(parser);
        Context lastContext = (Context)mConstructorArgs[0];
        mConstructorArgs[0] = mContext;
        View result = root;
        try {
            // Look for the root node.
            int type;
            while ((type = parser.next()) != XmlPullParser.START_TAG &&
                    type != XmlPullParser.END_DOCUMENT) {
                // Empty
            }
            if (type != XmlPullParser.START_TAG) {
                throw new InflateException(parser.getPositionDescription()
                        + ": No start tag found!");
            }
            final String name = parser.getName();
            if (TAG_MERGE.equals(name)) {
                if (root == null || !attachToRoot) {
                    throw new InflateException("<merge /> can be used only with a valid "
                            + "ViewGroup root and attachToRoot=true");
                }
                rInflate(parser, root, attrs, false, false);
            } else {
                // Temp is the root view that was found in the xml
                final View temp = createViewFromTag(root, name, attrs, false);
                ViewGroup.LayoutParams params = null;
                if (root != null) {
                    // Create layout params that match root, if supplied
                    params = root.generateLayoutParams(attrs);
                    if (!attachToRoot) {
                        // Set the layout params for temp if we are not
                        // attaching. (If we are, we use addView, below)
                        temp.setLayoutParams(params);
                    }
                }
                // Inflate all children under temp
                rInflate(parser, temp, attrs, true, true);
                // We are supposed to attach all the views we found (int temp)
                // to root. Do that now.
                if (root != null && attachToRoot) {
                    root.addView(temp, params);
                }
                // Decide whether to return the root that was passed in or the
                // top view found in xml.
                if (root == null || !attachToRoot) {
                    result = temp;
                }
            }
        } catch (XmlPullParserException e) {
            InflateException ex = new InflateException(e.getMessage());
            ex.initCause(e);
            throw ex;
        } catch (IOException e) {
            InflateException ex = new InflateException(
                    parser.getPositionDescription()
                    + ": " + e.getMessage());
            ex.initCause(e);
            throw ex;
        } finally {
            // Don't retain static reference on context.
            mConstructorArgs[0] = lastContext;
            mConstructorArgs[1] = null;
        }
        return result;
    }
}

/**
 * Creates a view from a tag name using the supplied attribute set.
 * <p>
 * If {@code inheritContext} is true and the parent is non-null, the view
 * will be inflated in parent view's context. If the view specifies a
 * &lt;theme&gt; attribute, the inflation context will be wrapped with the
 * specified theme.
 * <p>
 * Note: Default visibility so the BridgeInflater can override it.
 */
View createViewFromTag(View parent, String name, AttributeSet attrs, boolean inheritContext) {
//..
}

/**
 * For START_TAG or END_TAG events, the (local) name of the current
 * element is returned when namespaces are enabled. When namespace
 * processing is disabled, the raw name is returned.
 * For ENTITY_REF events, the entity name is returned.
 * If the current event is not START_TAG, END_TAG, or ENTITY_REF,
 * null is returned.
 * <p><b>Please note:</b> To reconstruct the raw element name
 *  when namespaces are enabled and the prefix is not null,
 * you will need to  add the prefix and a colon to localName..
 *
 */
String getName();

public interface Factory {
    /**
     * Hook you can supply that is called when inflating from a LayoutInflater.
     * You can use this to customize the tag names available in your XML
     * layout files.
     * 
     * <p>
     * Note that it is good practice to prefix these custom names with your
     * package (i.e., com.coolcompany.apps) to avoid conflicts with system
     * names.
     * 
     * @param name Tag name to be inflated.
     * @param context The context the view is being created in.
     * @param attrs Inflation attributes as specified in XML file.
     * 
     * @return View Newly created view. Return null for the default
     *         behavior.
     */
    public View onCreateView(String name, Context context, AttributeSet attrs);
}

public interface Factory2 extends Factory {
    /**
     * Version of {@link #onCreateView(String, Context, AttributeSet)}
     * that also supplies the parent that the view created view will be
     * placed in.
     *
     * @param parent The parent that the created view will be placed
     * in; <em>note that this may be null</em>.
     * @param name Tag name to be inflated.
     * @param context The context the view is being created in.
     * @param attrs Inflation attributes as specified in XML file.
     *
     * @return View Newly created view. Return null for the default
     *         behavior.
     */
    public View onCreateView(View parent, String name, Context context, AttributeSet attrs);
}

/**
 * Standard implementation of
 * {@link android.view.LayoutInflater.Factory#onCreateView} used when
 * inflating with the LayoutInflater returned by {@link #getSystemService}.
 * This implementation does nothing and is for
 * pre-{@link android.os.Build.VERSION_CODES#HONEYCOMB} apps.  Newer apps
 * should use {@link #onCreateView(View, String, Context, AttributeSet)}.
 *
 * @see android.view.LayoutInflater#createView
 * @see android.view.Window#getLayoutInflater
 */
@Nullable
public View onCreateView(String name, Context context, AttributeSet attrs) {
    return null;
}

/**
 * Standard implementation of
 * {@link android.view.LayoutInflater.Factory2#onCreateView(View, String, Context, AttributeSet)}
 * used when inflating with the LayoutInflater returned by {@link #getSystemService}.
 * This implementation handles <fragment> tags to embed fragments inside
 * of the activity.
 *
 * @see android.view.LayoutInflater#createView
 * @see android.view.Window#getLayoutInflater
 */
public View onCreateView(View parent, String name, Context context, AttributeSet attrs) {
    if (!"fragment".equals(name)) {
        return onCreateView(name, context, attrs);
    }

    return mFragments.onCreateView(parent, name, context, attrs);
}

protected LayoutInflater(LayoutInflater original, Context newContext) {
    mContext = newContext;
    mFactory = original.mFactory;
    mFactory2 = original.mFactory2;
    mPrivateFactory = original.mPrivateFactory;
    setFilter(original.mFilter);
}

/**
 * Attach a custom Factory interface for creating views while using
 * this LayoutInflater.  This must not be null, and can only be set once;
 * after setting, you can not change the factory.  This is
 * called on each element name as the xml is parsed. If the factory returns
 * a View, that is added to the hierarchy. If it returns null, the next
 * factory default {@link #onCreateView} method is called.
 * 
 * <p>If you have an existing
 * LayoutInflater and want to add your own factory to it, use
 * {@link #cloneInContext} to clone the existing instance and then you
 * can use this function (once) on the returned new instance.  This will
 * merge your own factory with whatever factory the original instance is
 * using.
 */
public void setFactory(Factory factory) {
    if (mFactorySet) {
        throw new IllegalStateException("A factory has already been set on this LayoutInflater");
    }
    if (factory == null) {
        throw new NullPointerException("Given factory can not be null");
    }
    mFactorySet = true;
    if (mFactory == null) {
        mFactory = factory;
    } else {
        mFactory = new FactoryMerger(factory, null, mFactory, mFactory2);
    }
}

/**
 * Like {@link #setFactory}, but allows you to set a {@link Factory2}
 * interface.
 */
public void setFactory2(Factory2 factory) {
    if (mFactorySet) {
        throw new IllegalStateException("A factory has already been set on this LayoutInflater");
    }
    if (factory == null) {
        throw new NullPointerException("Given factory can not be null");
    }
    mFactorySet = true;
    if (mFactory == null) {
        mFactory = mFactory2 = factory;
    } else {
        mFactory = mFactory2 = new FactoryMerger(factory, factory, mFactory, mFactory2);
    }
}

View view;
if (mFactory2 != null) {
    view = mFactory2.onCreateView(parent, name, viewContext, attrs);
} else if (mFactory != null) {
    view = mFactory.onCreateView(name, viewContext, attrs);
} else {
    view = null;
}

if (view == null && mPrivateFactory != null) {
    view = mPrivateFactory.onCreateView(parent, name, viewContext, attrs);
}

if (view == null) {
    final Object lastContext = mConstructorArgs[0];
    mConstructorArgs[0] = viewContext;
    try {
        if (-1 == name.indexOf('.')) {
            view = onCreateView(parent, name, attrs);
        } else {
            view = createView(name, null, attrs);
        }
    } finally {
        mConstructorArgs[0] = lastContext;
    }
}

return view;

/**
 * Low-level function for instantiating a view by name. This attempts to
 * instantiate a view class of the given <var>name</var> found in this
 * LayoutInflater's ClassLoader.
 * 
 * <p>
 * There are two things that can happen in an error case: either the
 * exception describing the error will be thrown, or a null will be
 * returned. You must deal with both possibilities -- the former will happen
 * the first time createView() is called for a class of a particular name,
 * the latter every time there-after for that class name.
 * 
 * @param name The full name of the class to be instantiated.
 * @param attrs The XML attributes supplied for this instance.
 * 
 * @return View The newly instantiated view, or null.
 */
public final View createView(String name, String prefix, AttributeSet attrs)
        throws ClassNotFoundException, InflateException {
        //...
}