Android ViewPager循环左右自动滑动加载Page，androidviewpager, package

Android ViewPager循环左右自动滑动加载Page，androidviewpager, package

    package zhangphil.auto_viewpager;      import java.util.ArrayList;      import android.support.v4.app.Fragment;      import android.support.v4.app.FragmentManager;      import android.support.v4.app.FragmentPagerAdapter;      import android.support.v4.view.ViewPager;      import android.support.v7.app.ActionBarActivity;      import android.view.Gravity;      import android.view.LayoutInflater;      import android.view.View;      import android.view.ViewGroup;      import android.widget.TextView;      import android.graphics.Color;      import android.os.Bundle;      import android.os.Handler;      import android.os.Message;      import android.os.SystemClock;      /**      * Android ViewPager循环左右自动滑动加载Page。      *        * 核心关键：使用 ViewPager的setCurrentItem(int index)左右自动循环加载。      * 思路：使用Android Handler，在Handler的handleMessage(Message msg)中收消息，收到消息就从msg中解析出需要加载的索引。      * 相应的，开辟一个线程，时隔两秒就用Handler发一个Message，触发Handler的handleMessage,从而调用ViewPager的setCurrentItem操作.      */      public class MainActivity extends ActionBarActivity {          private ViewPager mViewPager;          private final static String ID = "id";          private ArrayList<Fragment> mArrayList;          // 用以显示的Fragment总数，假设有5个.          private final int SIZE = 5;          private Handler handler;          private final int WHAT = 0xf01;          @Override          protected void onCreate(Bundle savedInstanceState) {              super.onCreate(savedInstanceState);              setContentView(R.layout.activity_main);              mArrayList = new ArrayList<Fragment>();              for (int i = 0; i < SIZE; i++) {                  Fragment f = new TestFragment();                  Bundle b = new Bundle();                  b.putInt(ID, i);                  f.setArguments(b);                  mArrayList.add(f);              }              mViewPager = (ViewPager) findViewById(R.id.viewpager);              FragmentPagerAdapter mPagerAdapter = new MyFragmentPagerAdapter(                      getSupportFragmentManager());              mViewPager.setAdapter(mPagerAdapter);              handler = new Handler() {                  @Override                  public void handleMessage(Message msg) {                      switch (msg.what) {                      case WHAT:                          int index = (Integer) msg.obj;                          mViewPager.setCurrentItem(index);                          break;                      }                  }              };              new Thread(new Runnable() {                  @Override                  public void run() {                      int i = 0;                      while (true) {                          // 当超过SIZE后，回绕，从头开始循环。                          i = i % SIZE;                          Message message = new Message();                          message.what = WHAT;                          message.obj = i;                          handler.sendMessage(message);                          // 休息两秒。                          SystemClock.sleep(2000);                          i++;                      }                  }              }).start();          }          private class MyFragmentPagerAdapter extends FragmentPagerAdapter {              public MyFragmentPagerAdapter(FragmentManager fm) {                  super(fm);              }              @Override              public Fragment getItem(int pos) {                  return mArrayList.get(pos);              }              @Override              public int getCount() {                  return mArrayList.size();              }          }          // 测试的Fragmnt，只显示一个Id，用于区别不同的Fragment。          public static class TestFragment extends Fragment {              private int Id;              @Override              public void onCreate(Bundle savedInstanceState) {                  super.onCreate(savedInstanceState);                  Bundle b = this.getArguments();                  Id = b.getInt(ID);              }              @Override              public View onCreateView(LayoutInflater inflater, ViewGroup container,                      Bundle savedInstanceState) {                  TextView tv = new TextView(getActivity());                  String str = "id: " + Id;                  tv.setTextColor(Color.LTGRAY);                  tv.setText(str);                  tv.setTextSize(50);                  tv.setGravity(Gravity.CENTER);                  return tv;              }          }      }  

activity_main.xml

    <?xml version="1.0" encoding="utf-8"?>      <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"          android:layout_width="match_parent"          android:layout_height="match_parent"          android:orientation="vertical" >          <FrameLayout              android:layout_width="match_parent"              android:layout_height="match_parent"              android:layout_weight="1" >              <android.support.v4.view.ViewPager                  android:id="@+id/viewpager"                  android:layout_width="match_parent"                  android:layout_height="match_parent" />          </FrameLayout>      </LinearLayout>