使用fragmentTableHost实现底部菜单栏

1底部菜单的几种实现方式：

TabHost+Activity

RadioButton+Fragment

这种方法使用RadioGroup来实现RadioButton的互斥选择，而且需要在activity中实现和判断点击事件

FragmentTableHost+Fragment

这个就比较简单了，只需要在layout文件中定义fragmentTableHost（需要support v4包），然后再在文件中创建出tabspec并添加到fragmentTableHost中就可以了，比radiobutton少了监听点击事件和判断点击事件，因为直接就对view和fragment进行了绑定

2.fragmentTableHost的结构：

3.创建流程：

下面代码是大概流程

mTabHost= (FragmentTabHost) findViewById(android.R.id.tabhost);

//1.invoke setup method
mTabHost.setup(this, getSupportFragmentManager(), R.id.realtabcontent);

//2.create TabSpec
TabHost.TabSpec spec=mTabHost.newTabSpec("home");

//3.create a view as indicator
View view=null;
view=getLayoutInflater().inflate(R.layout.tab_indicator,null);

//initialize the child view of indicator view
ImageView img= (ImageView) view.findViewById(R.id.icon_tab);
TextView text= (TextView) view.findViewById(R.id.tv_indicator);

img.setBackgroundResource(R.mipmap.icon_home);
text.setText("主页");

//4.set indicator for spec
spec.setIndicator(view);

//5.add spec to fragmentTabHost
mTabHost.addTab(spec, Fragment.class, null);

4.具体实现

主布局文件：

<?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"
    tools:context=".com.lc.store.activity.MainActivity">

    <!--这个framelayout才是真正使用indicator填充的view，在这里对height使用weight-->
    <FrameLayout
        android:id="@+id/realtabcontent"
        android:layout_width="match_parent"
        android:layout_weight="1"
        android:layout_height="0dp"
        android:background="@color/bg_color">
    </FrameLayout>

    <!--注意，这里的id是使用android自带的id-"@android:id/tabhost"-->
    <android.support.v4.app.FragmentTabHost
        android:id="@android:id/tabhost"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@color/white">

        <!--这里的宽和高都是使用weight，而且id也是使用android的tabcontent-->
        <FrameLayout
            android:id="@android:id/tabcontent"
            android:layout_width="0dp"
            android:layout_height="0dp"
            android:layout_weight="1"/>

    </android.support.v4.app.FragmentTabHost>
</LinearLayout>

fragment布局文件：

这里列出其中一个

<?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">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="@color/coral"
        android:text="@string/home"/>
</LinearLayout>

状态选择器：

这里只列出一个，其他的一样

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_selected="true" android:drawable="@mipmap/icon_home_press"/>
    <item android:drawable="@mipmap/icon_home"/>
</selector>

MainActivity：

package com.lc.store.activity;

import android.support.v4.app.FragmentTabHost;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TabHost;
import android.widget.TextView;

import com.lc.store.R;
import com.lc.store.activity.bean.Tab;
import com.lc.store.activity.fragment.CartFragment;
import com.lc.store.activity.fragment.CategoryFragment;
import com.lc.store.activity.fragment.HomeFragment;
import com.lc.store.activity.fragment.HotFragment;
import com.lc.store.activity.fragment.MineFragment;

import java.util.ArrayList;
import java.util.List;

/**
 * FragmentTabHost structure:
 * <p/>
 * fragmentTabHost->tabSpec->indicator->view->ImageView
 * ->TextView
 * ->tabSpec
 */
public class MainActivity extends AppCompatActivity {

    private FragmentTabHost mTabHost;

    private List<Tab> mTabs = new ArrayList<Tab>(5);

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

        mTabHost = (FragmentTabHost) findViewById(android.R.id.tabhost);

        initTab();
    }

    private void initTab() {
        Tab tab_home = new Tab(R.string.home, R.drawable.selector_icon_home, HomeFragment.class);
        Tab tab_hot = new Tab(R.string.hot, R.drawable.selector_icon_hot, HotFragment.class);
        Tab tab_category = new Tab(R.string.catagory, R.drawable.selector_icon_category, CategoryFragment.class);
        Tab tab_cart = new Tab(R.string.cart, R.drawable.selector_icon_cart, CartFragment.class);
        Tab tab_mine = new Tab(R.string.mine, R.drawable.selector_icon_mine, MineFragment.class);

        mTabs.add(tab_home);
        mTabs.add(tab_hot);
        mTabs.add(tab_category);
        mTabs.add(tab_cart);
        mTabs.add(tab_mine);

        //1.invoke setup method
        mTabHost.setup(this, getSupportFragmentManager(), R.id.realtabcontent);

        for(Tab t:mTabs){
            //2.create TabSpec
            TabHost.TabSpec spec = mTabHost.newTabSpec(getString(t.getTitle()));

            //3.create a view as indicator
            View view = null;
            view = getLayoutInflater().inflate(R.layout.tab_indicator, null);

            //initialize the child view of indicator view
            ImageView img = (ImageView) view.findViewById(R.id.icon_tab);
            TextView text = (TextView) view.findViewById(R.id.tv_indicator);

            img.setBackgroundResource(t.getIcon());
            text.setText(t.getTitle());

            //4.set indicator for spec
            spec.setIndicator(view);

            //5.add spec to fragmentTabHost
            mTabHost.addTab(spec, t.getFragment(), null);
        }

        //去掉分割线
        mTabHost.getTabWidget().setShowDividers(LinearLayout.SHOW_DIVIDER_NONE);
        mTabHost.setCurrentTab(2);

    }
}

 fragment：

注意，这里继承的是v4里面的fragment

package com.lc.store.activity.fragment;

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

import com.lc.store.R;

/**
 * Created by jiangbo on 2016/4/2.
 * Description
 */
public class HomeFragment extends Fragment{
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_home,container,false);
    }
}