// Create the tabs that make up the user interface.
mTabLayout = (TabLayout) findViewById(R.id.tabs);
final int tabCount = UiDataModel.getUiDataModel().getTabCount();
final boolean showTabLabel = getResources().getBoolean(R.bool.showTabLabel);
final boolean showTabHorizontally = getResources().getBoolean(R.bool.showTabHorizontally);
for (int i = 0; i < tabCount; i++) {
    final UiDataModel.Tab tabModel = UiDataModel.getUiDataModel().getTab(i);
    final @StringRes int labelResId = tabModel.getLabelResId();

    final TabLayout.Tab tab = mTabLayout.newTab()
            .setTag(tabModel)
            .setIcon(tabModel.getIconResId())
            .setContentDescription(labelResId);

    if (showTabLabel) {
        tab.setText(labelResId);
        tab.setCustomView(R.layout.tab_item);

        @SuppressWarnings("ConstantConditions")
        final TextView text = (TextView) tab.getCustomView()
                .findViewById(android.R.id.text1);
        text.setTextColor(mTabLayout.getTabTextColors());

        // Bind the icon to the TextView.
        final Drawable icon = tab.getIcon();
        if (showTabHorizontally) {
            // Remove the icon so it doesn't affect the minimum TabLayout height.
            tab.setIcon(null);
            text.setCompoundDrawablesRelativeWithIntrinsicBounds(icon, null, null, null);
        } else {
            text.setCompoundDrawablesRelativeWithIntrinsicBounds(null, icon, null, null);
        }
    }

/** Identifies each of the primary tabs within the application. */
public enum Tab {
    ALARMS(AlarmClockFragment.class, R.drawable.ic_tab_alarm, R.string.menu_alarm),
    CLOCKS(ClockFragment.class, R.drawable.ic_tab_clock, R.string.menu_clock),
    TIMERS(TimerFragment.class, R.drawable.ic_tab_timer, R.string.menu_timer),
    STOPWATCH(StopwatchFragment.class, R.drawable.ic_tab_stopwatch, R.string.menu_stopwatch);

    private final String mFragmentClassName;
    private final @DrawableRes int mIconResId;
    private final @StringRes int mLabelResId;

    Tab(Class fragmentClass, @DrawableRes int iconResId, @StringRes int labelResId) {
        mFragmentClassName = fragmentClass.getName();
        mIconResId = iconResId;
        mLabelResId = labelResId;
    }

    public String getFragmentClassName() { return mFragmentClassName; }
    public @DrawableRes int getIconResId() { return mIconResId; }
    public @StringRes int getLabelResId() { return mLabelResId; }
}

// Customize the view pager.
mFragmentTabPagerAdapter = new FragmentTabPagerAdapter(this);
mFragmentTabPager = (ViewPager) findViewById(R.id.desk_clock_pager);
// Keep all four tabs to minimize jank.
mFragmentTabPager.setOffscreenPageLimit(3);
// Set Accessibility Delegate to null so view pager doesn't intercept movements and
// prevent the fab from being selected.
mFragmentTabPager.setAccessibilityDelegate(null);
// Mirror changes made to the selected page of the view pager into UiDataModel.
mFragmentTabPager.addOnPageChangeListener(new PageChangeWatcher());
mFragmentTabPager.setAdapter(mFragmentTabPagerAdapter);

// Mirror changes made to the selected tab into UiDataModel.
mTabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
    @Override
    public void onTabSelected(TabLayout.Tab tab) {
        UiDataModel.getUiDataModel().setSelectedTab((UiDataModel.Tab) tab.getTag());
    }

    @Override
    public void onTabUnselected(TabLayout.Tab tab) {
    }

    @Override
    public void onTabReselected(TabLayout.Tab tab) {
    }
});

/**
 * This adapter produces the DeskClockFragments that are the content of the DeskClock tabs. The
 * adapter presents the tabs in LTR and RTL order depending on the text layout direction for the
 * current locale. To prevent issues when switching between LTR and RTL, fragments are registered
 * with the manager using position-independent tags, which is an important departure from
 * FragmentPagerAdapter.
 */
final class FragmentTabPagerAdapter extends PagerAdapter {

    private final DeskClock mDeskClock;

    /** The manager into which fragments are added. */
    private final FragmentManager mFragmentManager;

    /** A fragment cache that can be accessed before {@link #instantiateItem} is called. */
    private final Map<UiDataModel.Tab, DeskClockFragment> mFragmentCache;

    /** The active fragment transaction if one exists. */
    private FragmentTransaction mCurrentTransaction;

    /** The current fragment displayed to the user. */
    private Fragment mCurrentPrimaryItem;

    FragmentTabPagerAdapter(DeskClock deskClock) {
        mDeskClock = deskClock;
        mFragmentCache = new ArrayMap<>(getCount());
        mFragmentManager = deskClock.getFragmentManager();
    }

    @Override
    public int getCount() {
        return UiDataModel.getUiDataModel().getTabCount();
    }

    /**
     * @param position the left-to-right index of the fragment to be returned
     * @return the fragment displayed at the given {@code position}
     */
    DeskClockFragment getDeskClockFragment(int position) {
        // Fetch the tab the UiDataModel reports for the position.
        final UiDataModel.Tab tab = UiDataModel.getUiDataModel().getTabAt(position);

        // First check the local cache for the fragment.
        DeskClockFragment fragment = mFragmentCache.get(tab);
        if (fragment != null) {
            return fragment;
        }

        // Next check the fragment manager; relevant when app is rebuilt after locale changes
        // because this adapter will be new and mFragmentCache will be empty, but the fragment
        // manager will retain the Fragments built on original application launch.
        fragment = (DeskClockFragment) mFragmentManager.findFragmentByTag(tab.name());
        if (fragment != null) {
            fragment.setFabContainer(mDeskClock);
            mFragmentCache.put(tab, fragment);
            return fragment;
        }

        // Otherwise, build the fragment from scratch.
        final String fragmentClassName = tab.getFragmentClassName();
        fragment = (DeskClockFragment) Fragment.instantiate(mDeskClock, fragmentClassName);
        fragment.setFabContainer(mDeskClock);
        mFragmentCache.put(tab, fragment);
        return fragment;
    }

    @Override
    public void startUpdate(ViewGroup container) {
        if (container.getId() == View.NO_ID) {
            throw new IllegalStateException("ViewPager with adapter " + this + " has no id");
        }
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
        if (mCurrentTransaction == null) {
            mCurrentTransaction = mFragmentManager.beginTransaction();
        }

        // Use the fragment located in the fragment manager if one exists.
        final UiDataModel.Tab tab = UiDataModel.getUiDataModel().getTabAt(position);
        Fragment fragment = mFragmentManager.findFragmentByTag(tab.name());
        if (fragment != null) {
            mCurrentTransaction.attach(fragment);
        } else {
            fragment = getDeskClockFragment(position);
            mCurrentTransaction.add(container.getId(), fragment, tab.name());
        }

        if (fragment != mCurrentPrimaryItem) {
            FragmentCompat.setMenuVisibility(fragment, false);
            FragmentCompat.setUserVisibleHint(fragment, false);
        }

        return fragment;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
        if (mCurrentTransaction == null) {
            mCurrentTransaction = mFragmentManager.beginTransaction();
        }
        final DeskClockFragment fragment = (DeskClockFragment) object;
        fragment.setFabContainer(null);
        mCurrentTransaction.detach(fragment);
    }

    @Override
    public void setPrimaryItem(ViewGroup container, int position, Object object) {
        final Fragment fragment = (Fragment) object;
        if (fragment != mCurrentPrimaryItem) {
            if (mCurrentPrimaryItem != null) {
                FragmentCompat.setMenuVisibility(mCurrentPrimaryItem, false);
                FragmentCompat.setUserVisibleHint(mCurrentPrimaryItem, false);
            }
            if (fragment != null) {
                FragmentCompat.setMenuVisibility(fragment, true);
                FragmentCompat.setUserVisibleHint(fragment, true);
            }
            mCurrentPrimaryItem = fragment;
        }
    }

    @Override
    public void finishUpdate(ViewGroup container) {
        if (mCurrentTransaction != null) {
            mCurrentTransaction.commitAllowingStateLoss();
            mCurrentTransaction = null;
            mFragmentManager.executePendingTransactions();
        }
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
        return ((Fragment) object).getView() == view;
    }
}

new Thread(new Runnable() {
    @Override
    public void run() {
        new Handler();
    }
}).start();

Looper.prepareMainLooper();

ActivityThread thread = new ActivityThread();
thread.attach(false);

if (sMainThreadHandler == null) {
	sMainThreadHandler = thread.getHandler();
}

if (false) {
	Looper.myLooper().setMessageLogging(
      new LogPrinter(Log.DEBUG, "ActivityThread"));
}

// End of event ActivityThreadMain.
Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
Looper.loop();

/*
Initialize the current thread as a looper. This gives you a chance to create handlers that then reference this looper, before actually starting the loop. Be sure to call {@link #loop()} after calling this method, and end it by calling{@link #quit()}.
*/
public static void prepare() {
  	prepare(true);
}

private static void prepare(boolean quitAllowed) {
    if (sThreadLocal.get() != null) {
    	 throw new RuntimeException("Only one Looper may be created per thread");
    }
    sThreadLocal.set(new Looper(quitAllowed));
}
...
private Looper(boolean quitAllowed) {
    mQueue = new MessageQueue(quitAllowed);
    mThread = Thread.currentThread();
}

/** Return the Looper object associated with the current thread.  Returns null if the calling thread is not associated with a Looper.*/
public static @Nullable Looper myLooper() {
    return sThreadLocal.get();
}

/**
* Run the message queue in this thread. Be sure to call
* {@link #quit()} to end the loop.
*/
public static void loop() {
    final Looper me = myLooper();
    if (me == null) {
      	throw new RuntimeException("No Looper; Looper.prepare() wasn't called on this thread.");
    }
    final MessageQueue queue = me.mQueue;
	...
    for (;;) {
        Message msg = queue.next(); // might block
        if (msg == null) {
          // No message indicates that the message queue is quitting.
          return;
        }
        ...
        try {
            msg.target.dispatchMessage(msg);
            end = (slowDispatchThresholdMs == 0) ? 0 : SystemClock.uptimeMillis();
        } finally {
            if (traceTag != 0) {
                Trace.traceEnd(traceTag);
            }
        }
        ...
        msg.recycleUnchecked();
    }
}

/**
* Handle system messages here.
*/
public void dispatchMessage(Message msg) {
    if (msg.callback != null) {
        handleCallback(msg);
    } else {
        if (mCallback != null) {
            if (mCallback.handleMessage(msg)) {
              return;
            }
        }
        handleMessage(msg);
    }
}

@Override
public void run() {
    mTid = Process.myTid();
    Looper.prepare();
    synchronized (this) {
        mLooper = Looper.myLooper();
        notifyAll();
    }
    Process.setThreadPriority(mPriority);
    onLooperPrepared();
    Looper.loop();
    mTid = -1;
}

getFragmentManager().beginTransaction()
                        .replace(R.id.container, fragment)
                        .commit();

webView.getSettings().setDefaultTextEncodingName("UTF -8");//设置默认为utf-8
//webView.loadData(data, "text/html", "UTF -8"); //API提供的标准用法，无法解决乱码问题
webView.loadData(data, "text/html; charset=UTF-8", null);//这种写法可以正确解码

itemView.setOnCreateContextMenuListener((menu, v, menuInfo) -> {
    menu.add("稍后阅读").setOnMenuItemClickListener(item -> {
        Logger.e(easyNews.getNewsId());
        return false;
    });
});

public class RecyclerViewImplementsContextMenu extends RecyclerView {
    private AdapterView.AdapterContextMenuInfo contextMenuInfo;
    public RecyclerViewImplementsContextMenu(Context context) {
        super(context);
    }

    public RecyclerViewImplementsContextMenu(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public RecyclerViewImplementsContextMenu(Context context, @Nullable AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    public AdapterView.AdapterContextMenuInfo getContextMenuInfo() {
        return contextMenuInfo;
    }

    @Override
    public boolean showContextMenuForChild(View originalView) {
        int position = getChildAdapterPosition(originalView);
        long longId = getChildItemId(originalView);
        contextMenuInfo = new AdapterView.AdapterContextMenuInfo(originalView, position, longId);
        return super.showContextMenuForChild(originalView);
    }
}

public class Person implements Serializable{  
private String name;  
private int age;  
public String getName() {  
        return name;  
    }  
public void setName(String name) {  
        this.name = name;  
    }  
public int getAge() {  
        return age;  
        }  
public void setAge(int age) {  
        this.age = age;  
    }  
}  

Person person = new Person();  
person.setName("Tom");  
person.setAge(20);  
Intent intent = new Intent(FirstActivity.this, SecondActivity.class);  
intent.putExtra("person_data", person);  
startActivity(intent);  

Person person = (Person) getIntent().getSerializableExtra("person_data");  

public class Person implements Parcelable {  
    private String name;  
    private int age;  
      
    @Override  
    public int describeContents() {  
        // TODO Auto-generated method stub  
        return 0;  
    }  
  
    @Override  
    public void writeToParcel(Parcel dest, int flags) {  
        // TODO Auto-generated method stub  
        dest.writeString(name);  
        dest.writeInt(age);  
    }  
    public static final Parcelable.Creator<Person> CREATOR=new Parcelable.Creator<Person>() {  
  
        @Override  
        public Person createFromParcel(Parcel source) {  
            // TODO Auto-generated method stub  
            Person person=new Person();  
            person.name=source.readString();  
            person.age=source.readInt();  
            return person;  
        }  
  
        @Override  
        public Person[] newArray(int size) {  
            // TODO Auto-generated method stub  
            return new Person[size];  
        }  
    };  
  
}  

Person person = (Person) getIntent().getParcelableExtra("person_data");