fragment + viewpager 实现tabhost功能

今天用 fragment + viewpager+radiogroup 实现了tabhost功能

废话不多表，上代码：

主布局activity_main.xml

<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:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity"     android:orientation="vertical"    android:id="@+id/ll">    <RadioGroup         android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal"         android:id="@+id/rg">        <RadioButton             android:id="@+id/button1"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:textColor="@color/text_color_selector"             android:button="@null"            android:background="#ffff00"            android:layout_margin="2dp"            android:checked="true"            android:text="第一个"/>        <RadioButton             android:id="@+id/button2"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:textColor="@color/text_color_selector"            android:button="@null"            android:background="#ffff00"            android:layout_margin="2dp"            android:text="第二个"  />        <RadioButton             android:id="@+id/button3"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:textColor="@color/text_color_selector"            android:button="@null"            android:background="#ffff00"            android:layout_margin="2dp"            android:text="第三个" />        <RadioButton             android:id="@+id/button4"            android:layout_width="0dp"            android:layout_height="wrap_content"            android:layout_weight="1"            android:gravity="center"            android:textColor="@color/text_color_selector"            android:button="@null"            android:background="#ffff00"            android:layout_margin="2dp"            android:text="第四个"/>    </RadioGroup>     <android.support.v4.view.ViewPager        android:layout_width="match_parent"        android:layout_height="match_parent"        android:id="@+id/viewpager"/></LinearLayout>

字体颜色选择器：

text_color_selector.xml：

<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android">    <item android:state_checked="true" android:color="#ff0000"/>    <item android:color="#000000"/></selector>

fragment布局文件：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"     android:gravity="center"    android:background="#ff00ff"    >    <TextView         android:id="@+id/tv"        android:layout_width="match_parent"        android:layout_height="wrap_content"         android:gravity="center"        android:textColor="#ffff00"        android:textSize="27dp"/></LinearLayout>

主activity:

MainActivity.java

package com.example.fragmentviewpager;import java.util.ArrayList;import java.util.List;import android.app.Activity; import android.graphics.Color;import android.os.Bundle; import android.support.v4.app.Fragment;import android.support.v4.app.FragmentActivity;import android.support.v4.app.FragmentManager;import android.support.v4.view.ViewPager;import android.support.v4.view.ViewPager.OnPageChangeListener;import android.widget.RadioGroup;import android.widget.RadioGroup.OnCheckedChangeListener;import android.widget.Toast;public class MainActivity extends FragmentActivity implements OnCheckedChangeListener { private RadioGroup rGroup;ViewPager viewPager;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main); rGroup = (RadioGroup) findViewById(R.id.rg);rGroup.setOnCheckedChangeListener(this);viewPager = (ViewPager) findViewById(R.id.viewpager);MyAdapter adapter = getAdapter();viewPager.setAdapter(adapter); viewPager.setOnPageChangeListener(new MyPageChangeListener());        // 设置页面分隔线       viewPager.setPageMargin(8);       viewPager.setPageMarginDrawable(android.R.drawable.divider_horizontal_bright);}private MyAdapter getAdapter() {List<Fragment> list = new ArrayList<Fragment>() ; list.add(new MyFragment("第一个fragment",Color.RED));list.add(new MyFragment("第二个fragment",Color.GRAY));list.add(new MyFragment("第三个fragment",Color.GREEN));list.add(new MyFragment("第四个fragment",0xffff00ff));  return new MyAdapter(getSupportFragmentManager(), list); }@Overridepublic void onCheckedChanged(RadioGroup group, int checkedId) {switch (checkedId) {case R.id.button1:viewPager.setCurrentItem(0);//Toast.makeText(getApplicationContext(), "button1", 0).show();break;case R.id.button2:viewPager.setCurrentItem(1);//Toast.makeText(getApplicationContext(), "button2", 0).show();break;case R.id.button3:viewPager.setCurrentItem(2);//Toast.makeText(getApplicationContext(), "button3", 0).show();break;case R.id.button4:viewPager.setCurrentItem(3);//Toast.makeText(getApplicationContext(), "button4", 0).show();break;default:break;} }/*** 监听viewpager翻页操作* @author lenovo**/private class MyPageChangeListener implements OnPageChangeListener{@Overridepublic void onPageScrollStateChanged(int arg0) { }@Overridepublic void onPageScrolled(int arg0, float arg1, int arg2) { }@Overridepublic void onPageSelected(int posttion) {//Toast.makeText(getApplicationContext(), ""+arg0, 0).show(); switch (posttion) {case 0:rGroup.check(R.id.button1);break;case 1:rGroup.check(R.id.button2);break;case 2:rGroup.check(R.id.button3);break;case 3:rGroup.check(R.id.button4);break;default:break;}}}}

</pre><pre>

MyFragment.java

package com.example.fragmentviewpager;   import android.annotation.SuppressLint;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.TextView; @SuppressLint("ValidFragment")public class MyFragment extends Fragment {private String mtag;   private int background;    /**     * 构造方法      * @param mtag fragment标签     * @param bacground fragment背景颜色     */public MyFragment(String mtag,int bacground) {super();this.mtag = mtag;this.background = bacground;}@Overridepublic View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_layout, container,false);view.setBackgroundColor(background);TextView tv = (TextView) view.findViewById(R.id.tv);tv.setText(mtag);return view;//super.onCreateView(inflater, container, savedInstanceState);} }

MyAdapter.java

package com.example.fragmentviewpager;import java.util.List; import android.support.v4.app.Fragment;import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentPagerAdapter;public class MyAdapter extends FragmentPagerAdapter {    private List<Fragment> fragments;public MyAdapter(FragmentManager fm,List<Fragment> fragmentList) {super(fm); this.fragments = fragmentList;}@Overridepublic Fragment getItem(int location) { return fragments.get(location);}@Overridepublic int getCount() { return fragments.size();}}

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)

效果图：