android ViewPager案例

ViewPager和PagerAdapter

package com.example.mainframework02;

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

import android.app.Activity;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageButton;
import android.widget.LinearLayout;

public class TraditionalViewPagerAcvitity extends Activity {

	/**
	 * ViewPager
	 */
	private ViewPager mViewPager;
	/**
	 * ViewPager的适配器
	 */
	private PagerAdapter mAdapter;
	private List<View> mViews;
	private LayoutInflater mInflater;

	private int currentIndex;

	/**
	 * 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);
		mInflater = LayoutInflater.from(this);
		mViewPager = (ViewPager) findViewById(R.id.id_viewpager);
		//初始化View  把要显示的视图放进List中
		initView();
			
		mViewPager.setAdapter(mAdapter);
		// 滑动页面时响应的接口
		mViewPager.setOnPageChangeListener(new OnPageChangeListener() {
			@Override
			public void onPageSelected(int position) {
				// 重置底部按钮为初始状态
				resetTabBtn();
				// 改变底部按钮背景图片
				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) {
			}
		});

	}

	// 把底部按钮设置成默认
	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);
	}

	@SuppressWarnings("all")
	private void initView() {
		// 初始化 按钮对应的视图组件
		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);

		mViews = new ArrayList<View>();
		View first = mInflater.inflate(R.layout.main_tab_01, null);
		View second = mInflater.inflate(R.layout.main_tab_02, null);
		View third = mInflater.inflate(R.layout.main_tab_03, null);
		View fourth = mInflater.inflate(R.layout.main_tab_04, null);
		// 把要显示的内容放入到List中
		mViews.add(first);
		mViews.add(second);
		mViews.add(third);
		mViews.add(fourth);
		// 初始化PagerAdapter PageAdapter依赖视图List
		mAdapter = new PagerAdapter() {
			@Override
			public void destroyItem(ViewGroup container, int position,
					Object object) {
				container.removeView(mViews.get(position));
			}
			//滑动ViewPager时显示对应的视图
			@Override
			public Object instantiateItem(ViewGroup container, int position) {
				View view = mViews.get(position);
				container.addView(view);
				return view;
			}
			
			@Override
			public boolean isViewFromObject(View arg0, Object arg1) {
				return arg0 == arg1;
			}

			@Override
			public int getCount() {
				return mViews.size();
			}
		};
	}

}