ViewPager + Fragment实现滑动标签页

ViewPager 结合Fragment实现一个Activity里包含多个可滑动的标签页，每个标签页可以有独立的布局及响应。

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <LinearLayout 
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        
        
        <TextView 
            android:id="@+id/tv_guid1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1.0"
            android:gravity="center"
            android:text="特性1"
            android:textSize="18sp"/>
        <TextView  
            android:id="@+id/tv_guid2"  
            android:layout_width="wrap_content"  
            android:layout_height="wrap_content"  
            android:layout_weight="1.0"  
            android:gravity="center"  
            android:text="特性2"   
            android:textSize="18sp"/>  
  
        <TextView  
            android:id="@+id/tv_guid3"  
            android:layout_width="wrap_content"  
            android:layout_height="wrap_content"  
            android:layout_weight="1.0"  
            android:gravity="center"  
            android:text="特性3 "   
            android:textSize="18sp"/>  
  
        <TextView  
            android:id="@+id/tv_guid4"  
            android:layout_width="wrap_content"  
            android:layout_height="wrap_content"  
            android:layout_weight="1.0"  
            android:gravity="center"  
            android:text="特性4"   
            android:textSize="18sp"/>
    </LinearLayout>

    <ImageView 
        android:id="@+id/cursor"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:scaleType="matrix"
        android:src="@drawable/cursor"/>
    
    <android.support.v4.view.ViewPager
        android:id="@+id/viewpager"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:flipInterval="30"
        android:persistentDrawingCache="animation"/>
</LinearLayout>

MainActivity.java

package com.example.viewpagernfragment;

import java.util.ArrayList;

import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.DisplayMetrics;
import android.view.Menu;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.TranslateAnimation;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends FragmentActivity {
    private ViewPager mPager;
    private ArrayList<Fragment> fragmentList;
    private ImageView image;
    private TextView view1, view2, view3, view4;
    private int currIndex;//当前页卡编号
    private int bmpW;//横线图片宽度
    private int offset;//图片移动的偏移量

    
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        InitTextView();
        InitImage();
        InitViewPager();
    }
    
    
    /*
     * 初始化标签名
     */
    public void InitTextView(){
        view1 = (TextView)findViewById(R.id.tv_guid1);
        view2 = (TextView)findViewById(R.id.tv_guid2);
        view3 = (TextView)findViewById(R.id.tv_guid3);
        view4 = (TextView)findViewById(R.id.tv_guid4);
        
        view1.setOnClickListener(new txListener(0));
        view2.setOnClickListener(new txListener(1));
        view3.setOnClickListener(new txListener(2));
        view4.setOnClickListener(new txListener(3));
    }
    
    
    public class txListener implements View.OnClickListener{
        private int index=0;
        
        public txListener(int i) {
            index =i;
        }
        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            mPager.setCurrentItem(index);
        }
    }
    
    
    /*
     * 初始化图片的位移像素
     */
    public void InitImage(){
        image = (ImageView)findViewById(R.id.cursor);
        bmpW = BitmapFactory.decodeResource(getResources(), R.drawable.cursor).getWidth();
        DisplayMetrics dm = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getMetrics(dm);
        int screenW = dm.widthPixels;
        offset = (screenW/4 - bmpW)/2;
        
        //imgageview设置平移，使下划线平移到初始位置（平移一个offset）
        Matrix matrix = new Matrix();
        matrix.postTranslate(offset, 0);
        image.setImageMatrix(matrix);
    }
    
    /*
     * 初始化ViewPager
     */
    public void InitViewPager(){
        mPager = (ViewPager)findViewById(R.id.viewpager);
        fragmentList = new ArrayList<Fragment>();
        Fragment btFragment= new ButtonFragment();
        Fragment secondFragment = TestFragment.newInstance("this is second fragment");
        Fragment thirdFragment = TestFragment.newInstance("this is third fragment");
        Fragment fourthFragment = TestFragment.newInstance("this is fourth fragment");
        fragmentList.add(btFragment);
        fragmentList.add(secondFragment);
        fragmentList.add(thirdFragment);
        fragmentList.add(fourthFragment);
        
        //给ViewPager设置适配器
        mPager.setAdapter(new MyFragmentPagerAdapter(getSupportFragmentManager(), fragmentList));
        mPager.setCurrentItem(0);//设置当前显示标签页为第一页
        mPager.setOnPageChangeListener(new MyOnPageChangeListener());//页面变化时的监听器
    }

    
    public class MyOnPageChangeListener implements OnPageChangeListener{
        private int one = offset *2 +bmpW;//两个相邻页面的偏移量
        
        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) {
            // TODO Auto-generated method stub
            
        }
        
        @Override
        public void onPageScrollStateChanged(int arg0) {
            // TODO Auto-generated method stub
            
        }
        
        @Override
        public void onPageSelected(int arg0) {
            // TODO Auto-generated method stub
            Animation animation = new TranslateAnimation(currIndex*one,arg0*one,0,0);//平移动画
            currIndex = arg0;
            animation.setFillAfter(true);//动画终止时停留在最后一帧，不然会回到没有执行前的状态
            animation.setDuration(200);//动画持续时间0.2秒
            image.startAnimation(animation);//是用ImageView来显示动画的
            int i = currIndex + 1;
            Toast.makeText(MainActivity.this, "您选择了第"+i+"个页卡", Toast.LENGTH_SHORT).show();
        }
    }
    
    
    @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;
    }

}

谷歌官方认为，ViewPager应该和Fragment一起使用时，此时ViewPager的适配器是FragmentPagerAdapter，当你实现一个FragmentPagerAdapter,你必须至少覆盖以下方法:

getCount()

getItem()

如果ViewPager没有和Fragment一起，ViewPager的适配器是PagerAdapter，它是基类提供适配器来填充页面ViewPager内部，当你实现一个PagerAdapter,你必须至少覆盖以下方法:

    instantiateItem(ViewGroup, int)
    destroyItem(ViewGroup, int, Object)
    getCount()
    isViewFromObject(View, Object)

 

package com.example.viewpagernfragment;

import java.util.ArrayList;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;

public class MyFragmentPagerAdapter extends FragmentPagerAdapter{
    ArrayList<Fragment> list;
    public MyFragmentPagerAdapter(FragmentManager fm,ArrayList<Fragment> list) {
        super(fm);
        this.list = list;
        
    }
    
    
    @Override
    public int getCount() {
        return list.size();
    }
    
    @Override
    public Fragment getItem(int arg0) {
        return list.get(arg0);
    }
    
    
    
    
}

package com.example.viewpagernfragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;

public class ButtonFragment extends Fragment{
    Button myButton;
    
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.guide_1, container, false);//关联布局文件
        
        myButton = (Button)rootView.findViewById(R.id.mybutton);//根据rootView找到button
        
        //设置按键监听事件
        myButton.setOnClickListener(new View.OnClickListener() {
            
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Toast.makeText(ButtonFragment.this.getActivity(), "button is click!", Toast.LENGTH_SHORT).show();
            }
        });
        
        
        return rootView;
    }
}

package com.example.viewpagernfragment;

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 android.widget.TextView;

public class TestFragment extends Fragment {
    private static final String TAG = "TestFragment";
    private String hello;// = "hello android";
    private String defaultHello = "default value";

    static TestFragment newInstance(String s) {
        TestFragment newFragment = new TestFragment();
        Bundle bundle = new Bundle();
        bundle.putString("hello", s);
        newFragment.setArguments(bundle);
        
        //bundle还可以在每个标签里传送数据
        
        
        return newFragment;

    }



    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {
        Log.d(TAG, "TestFragment-----onCreateView");
        Bundle args = getArguments();
        hello = args != null ? args.getString("hello") : defaultHello;
        View view = inflater.inflate(R.layout.guide_2, container, false);
        TextView viewhello = (TextView) view.findViewById(R.id.tv);
        viewhello.setText(hello);
        return view;

    }

   

}

<?xml version="1.0" encoding="UTF-8"?>  
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  
    android:layout_width="fill_parent"  
    android:layout_height="fill_parent"  
    android:background="#ff0000ff" >  
    
    <Button 
        android:id="@+id/mybutton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="hit me"
        android:gravity="center"/>
</RelativeLayout>  

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:background="#158684" >


    <TextView
        android:id="@+id/tv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="TextView" />

</RelativeLayout>