/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/ package android.view; import android.graphics.Canvas;
import android.os.Handler;
import android.os.Message;
import android.os.Trace;
import android.widget.FrameLayout;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException; import android.content.Context;
import android.content.res.TypedArray;
import android.content.res.XmlResourceParser;
import android.util.AttributeSet;
import android.util.Xml; import java.io.IOException;
import java.lang.reflect.Constructor;
import java.util.HashMap; /**
* 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
*/
public abstract class LayoutInflater {
private final boolean DEBUG = false; /**
* This field should be made private, so it is hidden from the SDK.
* {@hide}
*/
protected final Context mContext; // these are optional, set by the caller
private boolean mFactorySet;
private Factory mFactory;
private Factory2 mFactory2;
private Factory2 mPrivateFactory;
private Filter mFilter; final Object[] mConstructorArgs = new Object[2]; static final Class<?>[] mConstructorSignature = new Class[] {
Context.class, AttributeSet.class}; private static final HashMap<String, Constructor<? extends View>> sConstructorMap =
new HashMap<String, Constructor<? extends View>>(); private HashMap<String, Boolean> mFilterMap; private static final String TAG_MERGE = "merge";
private static final String TAG_INCLUDE = "include";
private static final String TAG_1995 = "blink";
private static final String TAG_REQUEST_FOCUS = "requestFocus"; /**
* Hook to allow clients of the LayoutInflater to restrict the set of Views that are allowed
* to be inflated.
*
*/
public interface Filter {
/**
* Hook to allow clients of the LayoutInflater to restrict the set of Views
* that are allowed to be inflated.
*
* @param clazz The class object for the View that is about to be inflated
*
* @return True if this class is allowed to be inflated, or false otherwise
*/
@SuppressWarnings("unchecked")
boolean onLoadClass(Class clazz);
} 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);
} private static class FactoryMerger implements Factory2 {
private final Factory mF1, mF2;
private final Factory2 mF12, mF22; FactoryMerger(Factory f1, Factory2 f12, Factory f2, Factory2 f22) {
mF1 = f1;
mF2 = f2;
mF12 = f12;
mF22 = f22;
} public View onCreateView(String name, Context context, AttributeSet attrs) {
View v = mF1.onCreateView(name, context, attrs);
if (v != null) return v;
return mF2.onCreateView(name, context, attrs);
} public View onCreateView(View parent, String name, Context context, AttributeSet attrs) {
View v = mF12 != null ? mF12.onCreateView(parent, name, context, attrs)
: mF1.onCreateView(name, context, attrs);
if (v != null) return v;
return mF22 != null ? mF22.onCreateView(parent, name, context, attrs)
: mF2.onCreateView(name, context, attrs);
}
} /**
* Create a new LayoutInflater instance associated with a particular Context.
* Applications will almost always want to use
* {@link Context#getSystemService Context.getSystemService()} to retrieve
* the standard {@link Context#LAYOUT_INFLATER_SERVICE Context.INFLATER_SERVICE}.
*
* @param context The Context in which this LayoutInflater will create its
* Views; most importantly, this supplies the theme from which the default
* values for their attributes are retrieved.
*/
protected LayoutInflater(Context context) {
mContext = context;
} /**
* Create a new LayoutInflater instance that is a copy of an existing
* LayoutInflater, optionally with its Context changed. For use in
* implementing {@link #cloneInContext}.
*
* @param original The original LayoutInflater to copy.
* @param newContext The new Context to use.
*/
protected LayoutInflater(LayoutInflater original, Context newContext) {
mContext = newContext;
mFactory = original.mFactory;
mFactory2 = original.mFactory2;
mPrivateFactory = original.mPrivateFactory;
mFilter = original.mFilter;
} /**
* 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;
} /**
* 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); /**
* Return the context we are running in, for access to resources, class
* loader, etc.
*/
public Context getContext() {
return mContext;
} /**
* Return the current {@link Factory} (or null). This is called on each element
* name. If the factory returns a View, add that to the hierarchy. If it
* returns null, proceed to call onCreateView(name).
*/
public final Factory getFactory() {
return mFactory;
} /**
* Return the current {@link Factory2}. Returns null if no factory is set
* or the set factory does not implement the {@link Factory2} interface.
* This is called on each element
* name. If the factory returns a View, add that to the hierarchy. If it
* returns null, proceed to call onCreateView(name).
*/
public final Factory2 getFactory2() {
return mFactory2;
} /**
* 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 = new FactoryMerger(factory, factory, mFactory, mFactory2);
}
} /**
* @hide for use by framework
*/
public void setPrivateFactory(Factory2 factory) {
mPrivateFactory = factory;
} /**
* @return The {@link Filter} currently used by this LayoutInflater to restrict the set of Views
* that are allowed to be inflated.
*/
public Filter getFilter() {
return mFilter;
} /**
* Sets the {@link Filter} to by this LayoutInflater. If a view is attempted to be inflated
* which is not allowed by the {@link Filter}, the {@link #inflate(int, ViewGroup)} call will
* throw an {@link InflateException}. This filter will replace any previous filter set on this
* LayoutInflater.
*
* @param filter The Filter which restricts the set of Views that are allowed to be inflated.
* This filter will replace any previous filter set on this LayoutInflater.
*/
public void setFilter(Filter filter) {
mFilter = filter;
if (filter != null) {
mFilterMap = new HashMap<String, Boolean>();
}
} /**
* 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 node. Throws
* {@link InflateException} if there is an error. *
* <p>
* <em><strong>Important</strong></em> 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.
*
* @param parser XML dom node containing the description of the view
* hierarchy.
* @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(XmlPullParser parser, ViewGroup root) {
return inflate(parser, 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) {
if (DEBUG) System.out.println("INFLATING from resource: " + resource);
XmlResourceParser parser = getContext().getResources().getLayout(resource);
try {
return inflate(parser, root, attachToRoot);
} finally {
parser.close();
}
} /**
* Inflate a new view hierarchy from the specified XML node. Throws
* {@link InflateException} if there is an error.
* <p>
* <em><strong>Important</strong></em> 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.
*
* @param parser XML dom node containing the description of the view
* hierarchy.
* @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(XmlPullParser parser, ViewGroup root, boolean attachToRoot) {
synchronized (mConstructorArgs) {
Trace.traceBegin(Trace.TRACE_TAG_VIEW, "inflate"); 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 (DEBUG) {
System.out.println("**************************");
System.out.println("Creating root view: "
+ name);
System.out.println("**************************");
} 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);
} else {
// Temp is the root view that was found in the xml
View temp;
if (TAG_1995.equals(name)) {
temp = new BlinkLayout(mContext, attrs);
} else {
temp = createViewFromTag(root, name, attrs);
} ViewGroup.LayoutParams params = null; if (root != null) {
if (DEBUG) {
System.out.println("Creating params from root: " +
root);
}
// 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);
}
} if (DEBUG) {
System.out.println("-----> start inflating children");
}
// Inflate all children under temp
rInflate(parser, temp, attrs, true);
if (DEBUG) {
System.out.println("-----> done inflating children");
} // 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;
} Trace.traceEnd(Trace.TRACE_TAG_VIEW); return result;
}
} /**
* 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 {
Constructor<? extends View> constructor = sConstructorMap.get(name);
Class<? extends View> clazz = null; try {
Trace.traceBegin(Trace.TRACE_TAG_VIEW, name); if (constructor == null) {
// Class not found in the cache, see if it's real, and try to add it
clazz = mContext.getClassLoader().loadClass(
prefix != null ? (prefix + name) : name).asSubclass(View.class); if (mFilter != null && clazz != null) {
boolean allowed = mFilter.onLoadClass(clazz);
if (!allowed) {
failNotAllowed(name, prefix, attrs);
}
}
constructor = clazz.getConstructor(mConstructorSignature);
sConstructorMap.put(name, constructor);
} else {
// If we have a filter, apply it to cached constructor
if (mFilter != null) {
// Have we seen this name before?
Boolean allowedState = mFilterMap.get(name);
if (allowedState == null) {
// New class -- remember whether it is allowed
clazz = mContext.getClassLoader().loadClass(
prefix != null ? (prefix + name) : name).asSubclass(View.class); boolean allowed = clazz != null && mFilter.onLoadClass(clazz);
mFilterMap.put(name, allowed);
if (!allowed) {
failNotAllowed(name, prefix, attrs);
}
} else if (allowedState.equals(Boolean.FALSE)) {
failNotAllowed(name, prefix, attrs);
}
}
} Object[] args = mConstructorArgs;
args[1] = attrs; final View view = constructor.newInstance(args);
if (view instanceof ViewStub) {
// always use ourselves when inflating ViewStub later
final ViewStub viewStub = (ViewStub) view;
viewStub.setLayoutInflater(this);
}
return view; } catch (NoSuchMethodException e) {
InflateException ie = new InflateException(attrs.getPositionDescription()
+ ": Error inflating class "
+ (prefix != null ? (prefix + name) : name));
ie.initCause(e);
throw ie; } catch (ClassCastException e) {
// If loaded class is not a View subclass
InflateException ie = new InflateException(attrs.getPositionDescription()
+ ": Class is not a View "
+ (prefix != null ? (prefix + name) : name));
ie.initCause(e);
throw ie;
} catch (ClassNotFoundException e) {
// If loadClass fails, we should propagate the exception.
throw e;
} catch (Exception e) {
InflateException ie = new InflateException(attrs.getPositionDescription()
+ ": Error inflating class "
+ (clazz == null ? "<unknown>" : clazz.getName()));
ie.initCause(e);
throw ie;
} finally {
Trace.traceEnd(Trace.TRACE_TAG_VIEW);
}
} /**
* Throw an exception because the specified class is not allowed to be inflated.
*/
private void failNotAllowed(String name, String prefix, AttributeSet attrs) {
throw new InflateException(attrs.getPositionDescription()
+ ": Class not allowed to be inflated "
+ (prefix != null ? (prefix + name) : name));
} /**
* This routine is responsible for creating the correct subclass of View
* given the xml element name. Override it to handle custom view objects. If
* you override this in your subclass be sure to call through to
* super.onCreateView(name) for names you do not recognize.
*
* @param name The fully qualified class name of the View to be create.
* @param attrs An AttributeSet of attributes to apply to the View.
*
* @return View The View created.
*/
protected View onCreateView(String name, AttributeSet attrs)
throws ClassNotFoundException {
return createView(name, "android.view.", attrs);
} /**
* Version of {@link #onCreateView(String, AttributeSet)} that also
* takes the future parent of the view being constructed. The default
* implementation simply calls {@link #onCreateView(String, AttributeSet)}.
*
* @param parent The future parent of the returned view. <em>Note that
* this may be null.</em>
* @param name The fully qualified class name of the View to be create.
* @param attrs An AttributeSet of attributes to apply to the View.
*
* @return View The View created.
*/
protected View onCreateView(View parent, String name, AttributeSet attrs)
throws ClassNotFoundException {
return onCreateView(name, attrs);
} /*
* default visibility so the BridgeInflater can override it.
*/
View createViewFromTag(View parent, String name, AttributeSet attrs) {
if (name.equals("view")) {
name = attrs.getAttributeValue(null, "class");
} if (DEBUG) System.out.println("******** Creating view: " + name); try {
View view;
if (mFactory2 != null) view = mFactory2.onCreateView(parent, name, mContext, attrs);
else if (mFactory != null) view = mFactory.onCreateView(name, mContext, attrs);
else view = null; if (view == null && mPrivateFactory != null) {
view = mPrivateFactory.onCreateView(parent, name, mContext, attrs);
} if (view == null) {
if (-1 == name.indexOf('.')) {
view = onCreateView(parent, name, attrs);
} else {
view = createView(name, null, attrs);
}
} if (DEBUG) System.out.println("Created view is: " + view);
return view; } catch (InflateException e) {
throw e; } catch (ClassNotFoundException e) {
InflateException ie = new InflateException(attrs.getPositionDescription()
+ ": Error inflating class " + name);
ie.initCause(e);
throw ie; } catch (Exception e) {
InflateException ie = new InflateException(attrs.getPositionDescription()
+ ": Error inflating class " + name);
ie.initCause(e);
throw ie;
}
} /**
* Recursive method used to descend down the xml hierarchy and instantiate
* views, instantiate their children, and then call onFinishInflate().
*/
void rInflate(XmlPullParser parser, View parent, final AttributeSet attrs,
boolean finishInflate) throws XmlPullParserException, IOException { final int depth = parser.getDepth();
int type; while (((type = parser.next()) != XmlPullParser.END_TAG ||
parser.getDepth() > depth) && type != XmlPullParser.END_DOCUMENT) { if (type != XmlPullParser.START_TAG) {
continue;
} final String name = parser.getName(); if (TAG_REQUEST_FOCUS.equals(name)) {
parseRequestFocus(parser, parent);
} else if (TAG_INCLUDE.equals(name)) {
if (parser.getDepth() == 0) {
throw new InflateException("<include /> cannot be the root element");
}
parseInclude(parser, parent, attrs);
} else if (TAG_MERGE.equals(name)) {
throw new InflateException("<merge /> must be the root element");
} else if (TAG_1995.equals(name)) {
final View view = new BlinkLayout(mContext, attrs);
final ViewGroup viewGroup = (ViewGroup) parent;
final ViewGroup.LayoutParams params = viewGroup.generateLayoutParams(attrs);
rInflate(parser, view, attrs, true);
viewGroup.addView(view, params);
} else {
final View view = createViewFromTag(parent, name, attrs);
final ViewGroup viewGroup = (ViewGroup) parent;
final ViewGroup.LayoutParams params = viewGroup.generateLayoutParams(attrs);
rInflate(parser, view, attrs, true);
viewGroup.addView(view, params);
}
} if (finishInflate) parent.onFinishInflate();
} private void parseRequestFocus(XmlPullParser parser, View parent)
throws XmlPullParserException, IOException {
int type;
parent.requestFocus();
final int currentDepth = parser.getDepth();
while (((type = parser.next()) != XmlPullParser.END_TAG ||
parser.getDepth() > currentDepth) && type != XmlPullParser.END_DOCUMENT) {
// Empty
}
} private void parseInclude(XmlPullParser parser, View parent, AttributeSet attrs)
throws XmlPullParserException, IOException { int type; if (parent instanceof ViewGroup) {
final int layout = attrs.getAttributeResourceValue(null, "layout", 0);
if (layout == 0) {
final String value = attrs.getAttributeValue(null, "layout");
if (value == null) {
throw new InflateException("You must specifiy a layout in the"
+ " include tag: <include layout=\"@layout/layoutID\" />");
} else {
throw new InflateException("You must specifiy a valid layout "
+ "reference. The layout ID " + value + " is not valid.");
}
} else {
final XmlResourceParser childParser =
getContext().getResources().getLayout(layout); try {
final AttributeSet childAttrs = Xml.asAttributeSet(childParser); while ((type = childParser.next()) != XmlPullParser.START_TAG &&
type != XmlPullParser.END_DOCUMENT) {
// Empty.
} if (type != XmlPullParser.START_TAG) {
throw new InflateException(childParser.getPositionDescription() +
": No start tag found!");
} final String childName = childParser.getName(); if (TAG_MERGE.equals(childName)) {
// Inflate all children.
rInflate(childParser, parent, childAttrs, false);
} else {
final View view = createViewFromTag(parent, childName, childAttrs);
final ViewGroup group = (ViewGroup) parent; // We try to load the layout params set in the <include /> tag. If
// they don't exist, we will rely on the layout params set in the
// included XML file.
// During a layoutparams generation, a runtime exception is thrown
// if either layout_width or layout_height is missing. We catch
// this exception and set localParams accordingly: true means we
// successfully loaded layout params from the <include /> tag,
// false means we need to rely on the included layout params.
ViewGroup.LayoutParams params = null;
try {
params = group.generateLayoutParams(attrs);
} catch (RuntimeException e) {
params = group.generateLayoutParams(childAttrs);
} finally {
if (params != null) {
view.setLayoutParams(params);
}
} // Inflate all children.
rInflate(childParser, view, childAttrs, true); // Attempt to override the included layout's android:id with the
// one set on the <include /> tag itself.
TypedArray a = mContext.obtainStyledAttributes(attrs,
com.android.internal.R.styleable.View, 0, 0);
int id = a.getResourceId(com.android.internal.R.styleable.View_id, View.NO_ID);
// While we're at it, let's try to override android:visibility.
int visibility = a.getInt(com.android.internal.R.styleable.View_visibility, -1);
a.recycle(); if (id != View.NO_ID) {
view.setId(id);
} switch (visibility) {
case 0:
view.setVisibility(View.VISIBLE);
break;
case 1:
view.setVisibility(View.INVISIBLE);
break;
case 2:
view.setVisibility(View.GONE);
break;
} group.addView(view);
}
} finally {
childParser.close();
}
}
} else {
throw new InflateException("<include /> can only be used inside of a ViewGroup");
} final int currentDepth = parser.getDepth();
while (((type = parser.next()) != XmlPullParser.END_TAG ||
parser.getDepth() > currentDepth) && type != XmlPullParser.END_DOCUMENT) {
// Empty
}
} private static class BlinkLayout extends FrameLayout {
private static final int MESSAGE_BLINK = 0x42;
private static final int BLINK_DELAY = 500; private boolean mBlink;
private boolean mBlinkState;
private final Handler mHandler; public BlinkLayout(Context context, AttributeSet attrs) {
super(context, attrs);
mHandler = new Handler(new Handler.Callback() {
@Override
public boolean handleMessage(Message msg) {
if (msg.what == MESSAGE_BLINK) {
if (mBlink) {
mBlinkState = !mBlinkState;
makeBlink();
}
invalidate();
return true;
}
return false;
}
});
} private void makeBlink() {
Message message = mHandler.obtainMessage(MESSAGE_BLINK);
mHandler.sendMessageDelayed(message, BLINK_DELAY);
} @Override
protected void onAttachedToWindow() {
super.onAttachedToWindow(); mBlink = true;
mBlinkState = true; makeBlink();
} @Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow(); mBlink = false;
mBlinkState = true; mHandler.removeMessages(MESSAGE_BLINK);
} @Override
protected void dispatchDraw(Canvas canvas) {
if (mBlinkState) {
super.dispatchDraw(canvas);
}
}
}
}