android ViewPager和FragmentPagerAdapter结合使用

左右移动ViewPager时加载不同的Fragment

package com.example.mainframework03;

import java.util.ArrayList;
import java.util.List;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.widget.ImageButton;
import android.widget.LinearLayout;

public class MainActivity extends FragmentActivity {

	private ViewPager mViewPager;
	private FragmentPagerAdapter mAdapter;
	private List<Fragment> mFragments = new ArrayList<Fragment>();

	/**
	 * 底部四个按钮
	 */
	private LinearLayout mTabBtnWeixin;
	private LinearLayout mTabBtnFrd;
	private LinearLayout mTabBtnAddress;
	private LinearLayout mTabBtnSettings;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		mViewPager = (ViewPager) findViewById(R.id.id_viewpager);
		// 初始化底部按钮 并构造Fragment集合
		initView();
		// 初始化FragmentPagerAdapter
		mAdapter = new FragmentPagerAdapter(getSupportFragmentManager()) {
			@Override
			public int getCount() {
				return mFragments.size();
			}
			@Override
			public Fragment getItem(int arg0) {
				return mFragments.get(arg0);
			}
		};

		mViewPager.setAdapter(mAdapter);
		
		mViewPager.setOnPageChangeListener(new OnPageChangeListener() {

			private int currentIndex;

			@Override
			public void onPageSelected(int position) {
				// 重置底部按钮状态
				resetTabBtn();
				// 设置对应按钮为按着状态
				switch (position) {
				case 0:
					((ImageButton) mTabBtnWeixin
							.findViewById(R.id.btn_tab_bottom_weixin))
							.setImageResource(R.drawable.tab_weixin_pressed);
					break;
				case 1:
					((ImageButton) mTabBtnFrd
							.findViewById(R.id.btn_tab_bottom_friend))
							.setImageResource(R.drawable.tab_find_frd_pressed);
					break;
				case 2:
					((ImageButton) mTabBtnAddress
							.findViewById(R.id.btn_tab_bottom_contact))
							.setImageResource(R.drawable.tab_address_pressed);
					break;
				case 3:
					((ImageButton) mTabBtnSettings
							.findViewById(R.id.btn_tab_bottom_setting))
							.setImageResource(R.drawable.tab_settings_pressed);
					break;
				}
				currentIndex = position;
			}

			@Override
			public void onPageScrolled(int arg0, float arg1, int arg2) {
			}

			@Override
			public void onPageScrollStateChanged(int arg0) {
			}
		});

	}

	protected void resetTabBtn() {
		((ImageButton) mTabBtnWeixin.findViewById(R.id.btn_tab_bottom_weixin))
				.setImageResource(R.drawable.tab_weixin_normal);
		((ImageButton) mTabBtnFrd.findViewById(R.id.btn_tab_bottom_friend))
				.setImageResource(R.drawable.tab_find_frd_normal);
		((ImageButton) mTabBtnAddress.findViewById(R.id.btn_tab_bottom_contact))
				.setImageResource(R.drawable.tab_address_normal);
		((ImageButton) mTabBtnSettings
				.findViewById(R.id.btn_tab_bottom_setting))
				.setImageResource(R.drawable.tab_settings_normal);
	}

	private void initView() {

		mTabBtnWeixin = (LinearLayout) findViewById(R.id.id_tab_bottom_weixin);
		mTabBtnFrd = (LinearLayout) findViewById(R.id.id_tab_bottom_friend);
		mTabBtnAddress = (LinearLayout) findViewById(R.id.id_tab_bottom_contact);
		mTabBtnSettings = (LinearLayout) findViewById(R.id.id_tab_bottom_setting);

		MainTab01 tab01 = new MainTab01();
		MainTab02 tab02 = new MainTab02();
		MainTab03 tab03 = new MainTab03();
		MainTab04 tab04 = new MainTab04();
		mFragments.add(tab01);
		mFragments.add(tab02);
		mFragments.add(tab03);
		mFragments.add(tab04);
	}
}