FragmentTabHostAutoDemo【FragmentTabHost可滑动的选项卡】

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#3F51B5</color>
    <color name="colorPrimaryDark">#303F9F</color>
    <color name="colorAccent">#FF4081</color>

    <!-- *********************************顶部选项卡区域********************************* -->
    <!-- 顶部选项卡下划线背景色 -->
    <color name="tab_auto_normal_top">#00ffffff</color>
    <color name="tab_auto_selected_top">#3090d9</color>
    <!-- 顶部选项卡文本颜色 -->
    <color name="tab_text_normal_top">#191919</color>
    <color name="tab_text_selected_top">#3090d9</color>


</resources>

<resources>
    <!-- Default screen margins, per the Android Design guidelines. -->
    <dimen name="activity_horizontal_margin">16dp</dimen>
    <dimen name="activity_vertical_margin">16dp</dimen>

    <!-- *********************************顶部选项卡区域********************************* -->
    <!-- 选项卡的内边距 -->
    <dimen name="tab_top_auto_padding">10dp</dimen>
    <!-- 选项卡标题的文字大小 -->
    <dimen name="tab_top_auto_title_size">18sp</dimen>
    <!-- 选项卡标题的下划线高度 -->
    <dimen name="tab_top_auto_height">3dp</dimen>
</resources>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.why.project.fragmenttabhostautodemo">

    <!-- ======================授权访问网络（HttpUtil）========================== -->
    <!-- 允许程序打开网络套接字 -->
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<!-- 顶部选项卡区域 -->
<com.why.project.fragmenttabhostautodemo.views.tab.MyFragmentTabHost
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/tab_top_auto_ftabhost_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    >

    <!-- 必须要有LinearLayout，因为FragmentTabHost属于FrameLayout帧布局 -->
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <!-- 选项卡区域 -->
        <!--注意：原来的配置：android:layout_height="?attr/actionBarSize"-->
        <TabWidget
            android:id="@android:id/tabs"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="top|center_horizontal"/>

        <!-- 分割线 -->
        <View
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="#cfcfcf">
        </View>

        <!-- 碎片切换区域，且其id必须为@android:id/tabcontent -->
        <FrameLayout
            android:id="@android:id/tabcontent"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            />

    </LinearLayout>

</com.why.project.fragmenttabhostautodemo.views.tab.MyFragmentTabHost>

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

    <!-- webview -->
    <WebView
        android:id="@+id/web_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"></WebView>

</LinearLayout>

package com.why.project.fragmenttabhostautodemo.fragment;

import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebView;
import android.webkit.WebViewClient;

import com.why.project.fragmenttabhostautodemo.R;


/**
 * @Created HaiyuKing
 * @Used  首页界面——碎片界面
 */
public class WebViewFragment extends BaseFragment{
    
    private static final String TAG = "WebViewFragment";
    /**View实例*/
    private View myView;

    private WebView web_view;

    /**传递过来的参数*/
    private String bundle_param;

    //重写
    public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) {


        //使用FragmentTabHost时，Fragment之间切换时每次都会调用onCreateView方法，导致每次Fragment的布局都重绘，无法保持Fragment原有状态。
        //http://www.cnblogs.com/changkai244/p/4110173.html
        if(myView==null){
            myView = inflater.inflate(R.layout.fragment_web, container, false);
            //接收传参
            Bundle bundle = this.getArguments();
            bundle_param = bundle.getString("param");
        }
        //缓存的rootView需要判断是否已经被加过parent， 如果有parent需要从parent删除，要不然会发生这个rootview已经有parent的错误。
        ViewGroup parent = (ViewGroup) myView.getParent();
        if (parent != null) {
            parent.removeView(myView);
        }

        return myView;
    }
    
    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onActivityCreated(savedInstanceState);
        
        //初始化控件以及设置
        initView();
        //初始化数据
        initData();
        //初始化控件的点击事件
          initEvent();
    }
    @Override
    public void onResume() {
        super.onResume();
    }
    
    @Override
    public void onPause() {
        super.onPause();
    }
    
    @Override
    public void onDestroy() {
        super.onDestroy();
    }
    
    /**
     * 初始化控件
     */
    private void initView() {
        web_view = (WebView) myView.findViewById(R.id.web_view);
        //设置支持js脚本
//        web_view.getSettings().setJavaScriptEnabled(true);
        web_view.setWebViewClient(new WebViewClient() {
            /**
             * 重写此方法表明点击网页内的链接由自己处理，而不是新开Android的系统browser中响应该链接。
             */
            @Override
            public boolean shouldOverrideUrlLoading(WebView webView, String url) {
                //webView.loadUrl(url);
                return false;
            }
        });
    }
    
    /**
     * 初始化数据
     */
    public void initData() {
        Log.e("tag","{initData}bundle_param="+bundle_param);
        web_view.loadUrl(bundle_param);//加载网页
    }

    /**
     * 初始化点击事件
     * */
    private void initEvent(){
    }
    
}

package com.why.project.fragmenttabhostautodemo;

import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TabHost;
import android.widget.TabWidget;
import android.widget.TextView;
import android.widget.Toast;

import com.why.project.fragmenttabhostautodemo.fragment.WebViewFragment;
import com.why.project.fragmenttabhostautodemo.views.tab.MyFragmentTabHost;

import java.util.ArrayList;

public class MainActivity extends AppCompatActivity {

    private MyFragmentTabHost mTopAutoFTabHostLayout;
    //选项卡子类集合
    private ArrayList<TabItem> tabItemList = new ArrayList<TabItem>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initTabList();
        initFTabHostLayout();
        setFTabHostData();
        initEvents();
    }

    /**
     * 初始化选项卡数据集合
     */
    private void initTabList() {
        //底部选项卡对应的Fragment类使用的是同一个Fragment，那么需要考虑切换Fragment时避免重复加载UI的问题】
        tabItemList.add(new TabItem(this,"百度",WebViewFragment.class));
        tabItemList.add(new TabItem(this,"CSDN",WebViewFragment.class));
        tabItemList.add(new TabItem(this,"博客园",WebViewFragment.class));
        tabItemList.add(new TabItem(this,"极客头条",WebViewFragment.class));
        tabItemList.add(new TabItem(this,"优设",WebViewFragment.class));
        tabItemList.add(new TabItem(this,"玩Android",WebViewFragment.class));
        tabItemList.add(new TabItem(this,"掘金",WebViewFragment.class));
    }

    /**
     * 初始化FragmentTabHost
     */
    private void initFTabHostLayout() {
        //实例化
        mTopAutoFTabHostLayout = (MyFragmentTabHost) findViewById(R.id.tab_top_auto_ftabhost_layout);
        mTopAutoFTabHostLayout.setup(this, getSupportFragmentManager(), android.R.id.tabcontent);//最后一个参数是碎片切换区域的ID值
        // 去掉分割线
        mTopAutoFTabHostLayout.getTabWidget().setDividerDrawable(null);

    }

    /**
     * 设置选项卡的内容
     */
    private void setFTabHostData() {
        //Tab存在于TabWidget内，而TabWidget是存在于TabHost内。与此同时，在TabHost内无需在写一个TabWidget，系统已经内置了一个TabWidget
        for (int i = 0; i < tabItemList.size(); i++) {
            //实例化一个TabSpec,设置tab的名称和视图
            TabHost.TabSpec spec = mTopAutoFTabHostLayout.newTabSpec(tabItemList.get(i).getTabTitle()).setIndicator(tabItemList.get(i).getTabView());
            // 添加Fragment
            //初始化传参：http://bbs.csdn.net/topics/391059505
            Bundle bundle = new Bundle();
            if(i == 0 ){
                bundle.putString("param", "http://www.baidu.com");
            }else if(i == 1){
                bundle.putString("param", "http://blog.csdn.net");
            }else if(i == 2){
                bundle.putString("param", "http://www.cnblogs.com");
            }else if(i == 3){
                bundle.putString("param", "http://geek.csdn.net/mobile");
            }else if(i == 4){
                bundle.putString("param", "http://www.uisdc.com/");
            }else if(i == 5){
                bundle.putString("param", "http://www.wanandroid.com/index");
            }else if(i == 6){
                bundle.putString("param", "https://juejin.im/");
            }

            mTopAutoFTabHostLayout.addTab(spec, tabItemList.get(i).getTabFragment(), bundle);
        }

        //实现可滑动的选项卡https://stackoverflow.com/questions/14598819/fragmenttabhost-with-horizontal-scroll
        TabWidget tabWidget = (TabWidget) findViewById(android.R.id.tabs);
        LinearLayout tabWidgetParent = (LinearLayout) tabWidget.getParent();
        HorizontalScrollView hs = new HorizontalScrollView(this);
        hs.setLayoutParams(new FrameLayout.LayoutParams(
                FrameLayout.LayoutParams.WRAP_CONTENT,
                FrameLayout.LayoutParams.WRAP_CONTENT));
        tabWidgetParent.addView(hs, 0);
        tabWidgetParent.removeView(tabWidget);
        hs.addView(tabWidget);
        hs.setHorizontalScrollBarEnabled(false);

        //默认选中第一项
        mTopAutoFTabHostLayout.setCurrentTab(0);
        tabItemList.get(0).setChecked(true);
    }

    private void initEvents() {
        //选项卡的切换事件监听
        mTopAutoFTabHostLayout.setOnTabChangedListener(new TabHost.OnTabChangeListener() {
            @Override
            public void onTabChanged(String tabId) {
                //重置Tab样式
                for (int i = 0; i < tabItemList.size(); i++) {
                    TabItem tabitem = tabItemList.get(i);
                    if (tabId.equals(tabitem.getTabTitle())) {
                        tabitem.setChecked(true);
                    } else {
                        tabitem.setChecked(false);
                    }
                }

                Toast.makeText(MainActivity.this, tabId, Toast.LENGTH_SHORT).show();

            }
        });
    }

    /**
     * 选项卡子项类*/
    class TabItem{

        private Context mContext;

        private TextView top_title;
        private TextView top_underline;

        //底部选项卡对应的文字
        private String tabTitle;
        //底部选项卡对应的Fragment类
        private Class<? extends Fragment> tabFragment;

        public TabItem(Context mContext, String tabTitle, Class tabFragment){
            this.mContext = mContext;

            this.tabTitle = tabTitle;
            this.tabFragment = tabFragment;
        }

        public Class<? extends Fragment> getTabFragment() {
            return tabFragment;
        }

        public String getTabTitle() {
            return tabTitle;
        }

        /**
         * 获取底部选项卡的布局实例并初始化设置*/
        private View getTabView() {
            //============引用选项卡的各个选项的布局文件=================
            View toptabitemView = View.inflate(mContext,R.layout.tab_top_auto_item, null);

            //===========选项卡的根布局==========
            RelativeLayout toptabLayout = (RelativeLayout) toptabitemView.findViewById(R.id.toptabLayout);

            //===========设置选项卡的文字==========
            top_title = (TextView) toptabitemView.findViewById(R.id.top_title);
            //设置选项卡的文字
            top_title.setText(tabTitle);

            //===========设置选项卡控件的下划线【不能使用View，否则setWidth不能用】==========
            top_underline = (TextView) toptabitemView.findViewById(R.id.top_underline);
            //设置下划线的宽度值==根布局的宽度
            top_title.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
            Log.w("why", "top_title.getMeasuredWidth()="+top_title.getMeasuredWidth());
            toptabLayout.measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
            Log.w("why", "toptabLayout.getMeasuredWidth()="+toptabLayout.getMeasuredWidth());
            top_underline.setWidth(top_title.getMeasuredWidth());//手动设置下划线的宽度值

            return toptabitemView;
        }

        /**
         * 更新文字颜色
         */
        public void setChecked(boolean isChecked) {
            if(tabTitle != null){
                if(isChecked){
                    //修改文字颜色
                    top_title.setTextColor(getResources().getColor(R.color.tab_text_selected_top));
                    //修改下划线的颜色
                    top_underline.setBackgroundColor(getResources().getColor(R.color.tab_auto_selected_top));
                }else{
                    //修改文字颜色
                    top_title.setTextColor(getResources().getColor(R.color.tab_text_normal_top));
                    //修改下划线的颜色
                    top_underline.setBackgroundColor(getResources().getColor(R.color.tab_auto_normal_top));
                }
            }
        }
    }
}