ViewPager+Fragment替代TabHost效果的简单示例

本示例旨在展示fragment替代tabhost的效果，具体的业务逻辑还要根据这个示例进行扩展。

效果图如下：

主Activity代码：

package com.llb.view;

import java.util.ArrayList;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.RadioButton;
import com.llb.adapter.MyViewPagerAdapter;
import com.llb.fragment.ActivityFragment;
import com.llb.fragment.FriendFragment;
import com.llb.fragment.JobFragment;

public class MainActivity extends FragmentActivity implements OnPageChangeListener {
    private ViewPager pager;
    private PagerAdapter mAdapter;

    private ArrayList<Fragment> fragments;
    private ArrayList<RadioButton> title = new ArrayList<RadioButton>();// 三个标题

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);// /slidingmenu里面重写了
        initView();// 初始化控件
        initTitle();
        initViewPager();
    }

    /**
     * 初始化视图
     */
    private void initView() {
        pager = (ViewPager) findViewById(R.id.pager);// 初始化控件
        fragments = new ArrayList<Fragment>();// 初始化数据
        fragments.add(new ActivityFragment());
        fragments.add(new JobFragment());
        fragments.add(new FriendFragment());
    }

    /**
     * 初始化ViewPager
     */
    private void initViewPager() {
        mAdapter = new MyViewPagerAdapter(getSupportFragmentManager(), fragments);
        pager.setAdapter(mAdapter);
        pager.setOnPageChangeListener(this);
        pager.setCurrentItem(0);// 设置成当前第一个
    }

    /**
     * 初始化几个用来显示title的RadioButton
     */
    private void initTitle() {
        title.add((RadioButton) findViewById(R.id.title1));// 三个title标签
        title.add((RadioButton) findViewById(R.id.title2));
        title.add((RadioButton) findViewById(R.id.title3));
        title.get(0).setOnClickListener(new MyOnClickListener(0));// 设置响应
        title.get(1).setOnClickListener(new MyOnClickListener(1));
        title.get(2).setOnClickListener(new MyOnClickListener(2));
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    /**
     * 重写OnClickListener的响应函数，主要目的就是实现点击title时，pager会跟着响应切换
     *
     * @author llb
     *
     */
    private class MyOnClickListener implements OnClickListener {
        private int index;

        public MyOnClickListener(int index) {
            this.index = index;
        }

        @Override
        public void onClick(View v) {
            pager.setCurrentItem(index);// 把viewpager的视图切过去，实现捏造title跟pager的联动
            title.get(index).setChecked(true);// 设置被选中，否则布局里面的背景不会切换
        }

    }

    /**
     * 下面三个是OnPageChangeListener的接口函数
     */
    @Override
    public void onPageScrollStateChanged(int arg0) {
    }

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

    @Override
    public void onPageSelected(int arg0) {
        Log.i("slide", "onPageSelected+agr0=" + arg0);
        title.get(arg0).setChecked(true);// 保持页面跟按钮的联动
    }
}

Fragment 页面  ，贴一个的代码，其他2个与此类似

package com.llb.fragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import com.llb.view.R;

public class ActivityFragment extends Fragment {
    private View view;// 缓存页面

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Log.i("slide", "ActivityFragment--onCreate");
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        Log.i("slide", "ActivityFragment-onCreateView");
        if (view == null) {
            view = inflater.inflate(R.layout.activity_fragment, container, false);
        }
        ViewGroup parent = (ViewGroup) view.getParent();
        if (parent != null) {
            parent.removeView(view);// 先移除
        }
        return view;
    }

    @Override
    public void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        Log.i("slide", "ActivityFragment--onPause");
    }

    @Override
    public void onStop() {
        // TODO Auto-generated method stub
        super.onStop();
        Log.i("slide", "ActivityFragment--onStop");
    }

    @Override
    public void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        Log.i("slide", "ActivityFragment--onDestroy");
    }
}

MyViewPagerAdapter的代码：

package com.llb.adapter;

import java.util.ArrayList;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
/**
 * 这个adapter里面有Fragment数组
 * @author llb
 *
 */
public class MyViewPagerAdapter extends FragmentPagerAdapter {
    private ArrayList<Fragment> fragments;//需要添加到上面的Fragment

    public MyViewPagerAdapter(FragmentManager fm) {
        super(fm);
    }
    /**
     * 自定义的构造函数
     * @param fm
     * @param fragments ArrayList<Fragment>
     */
    public MyViewPagerAdapter(FragmentManager fm,ArrayList<Fragment> fragments) {
        super(fm);
        this.fragments = fragments;
    }
    @Override
    public Fragment getItem(int arg0) {
        return fragments.get(arg0);//返回Fragment对象
    }
    @Override
    public int getCount() {
        return fragments.size();//返回Fragment的个数
    }
}

整个项目源码如下：http://download.csdn.net/detail/abc13939746593/6656809