ViewPager，使用Fragment实现

　　效果如图：

使用Fragment实现tab的缺点就是不能够滑动。不过应该也算优点，具体场景可以自由选择。

完整代码：imooc-tab022fragment，在我的百度云网盘上。

MainAcgtivity.java

package com.example.imooc_tab02;

import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;
import android.widget.LinearLayout;

public class MainActivity extends FragmentActivity implements OnClickListener {
    // tabs
    LinearLayout tab_weixin, tab_frd, tab_addr, tab_settings;
    // ImageButton
    ImageButton btn_weixin, btn_py, btn_txl, btn_sz;

    tab01 t1;
    tab02 t2;
    tab03 t3;
    tab04 t4;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        t1 = new tab01();
        t2 = new tab02();
        t3 = new tab03();
        t4 = new tab04();
        initView();
        initEvents();
        
        /*
         * 把tab添加到FrameLayout中，transaction的前一个参数是FrameLayout
         * 的id,第二个参数是Fragment的继承类的实例对象
         */
        // transaction.add(R.id.id_fragment, t1);

    }

    private void initEvents() {
        tab_weixin.setOnClickListener(this);
        tab_frd.setOnClickListener(this);
        tab_addr.setOnClickListener(this);
        tab_settings.setOnClickListener(this);
        tab_addr.callOnClick();//设置通讯录为默认点击，
    }

    private void initView() {
        // TODO Auto-generated method stub
        tab_weixin = (LinearLayout) findViewById(R.id.id_tab_weixin2);
        // tab_frd,tab_addr,tab_settings
        tab_frd = (LinearLayout) findViewById(R.id.id_tab_frd2);
        tab_addr = (LinearLayout) findViewById(R.id.id_tab_address2);
        tab_settings = (LinearLayout) findViewById(R.id.id_tab_settings2);

        // btn_weixin,btn_py,btn_txl,btn_sz;
        btn_weixin = (ImageButton) findViewById(R.id.id_imgbtn_wx);
        btn_py = (ImageButton) findViewById(R.id.id_imgbtn_py);
        btn_txl = (ImageButton) findViewById(R.id.id_imgbtn_txl);
        btn_sz = (ImageButton) findViewById(R.id.id_imgbtn_sz);
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        FragmentManager manager = getSupportFragmentManager();
        FragmentTransaction transaction = manager.beginTransaction();
        hideFragment(transaction);
        switch (v.getId()) {
        case R.id.id_tab_weixin2:
            resetImg();
            if(!t1.isAdded()){
                //如果fragment对象t1没有被添加，那么就添加并显示
                transaction.add(R.id.id_fragment, t1);
            }
            transaction.show(t1);
            btn_weixin.setImageResource(R.drawable.tab_weixin_pressed);
            break;
        case R.id.id_tab_frd2:
            resetImg();
            if (!t2.isAdded()) {
                transaction.add(R.id.id_fragment, t2);
            } 
            transaction.show(t2);
            btn_py.setImageResource(R.drawable.tab_find_frd_pressed);
            break;
        case R.id.id_tab_address2:
            resetImg();
            if (!t3.isAdded()) {
                transaction.add(R.id.id_fragment, t3);
            } 
            transaction.show(t3);
            btn_txl.setImageResource(R.drawable.tab_address_pressed);
            break;
        case R.id.id_tab_settings2:
            resetImg();
            if (!t4.isAdded()) {
                transaction.add(R.id.id_fragment, t4);
            } 
            transaction.show(t4);
            btn_sz.setImageResource(R.drawable.tab_settings_pressed);
            break;

        default:
            break;
        }
        transaction.commit();
    }

    private void hideFragment(FragmentTransaction transaction) {
        System.out.println("====开始hideFragment()...====");
        // TODO Auto-generated method stub
        if (t1 != null) {
            System.out.println("hide(t1)...");
            transaction.hide(t1);
        }
        if (t2 != null) {
            System.out.println("hide(t2)...");
            transaction.hide(t2);
        }
        if (t3 != null) {
            System.out.println("hide(t3)...");
            transaction.hide(t3);
        }
        if (t4 != null) {
            System.out.println("hide(t4)...");
            transaction.hide(t4);
        }
    }

    // 重置按钮为灰色的
    public void resetImg() {
        btn_weixin.setImageResource(R.drawable.tab_weixin_normal);
        btn_py.setImageResource(R.drawable.tab_find_frd_normal);
        btn_txl.setImageResource(R.drawable.tab_address_normal);
        btn_sz.setImageResource(R.drawable.tab_settings_normal);
    }
}