BottomNavigationView+fragment 实现底部菜单栏

第三方大神：GitHub - aurelhubert/ahbottomnavigation，GitHub - roughike/BottomBar， Ashok-Varma/BottomNavigation。

直接上代码：

activity_main：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/container"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical"    tools:context="com.example.administrator.tablayout.MainActivity">    <FrameLayout        android:id="@+id/content"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"        android:visibility="visible">        <TextView            android:id="@+id/message"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:layout_marginBottom="@dimen/activity_vertical_margin"            android:layout_marginLeft="@dimen/activity_horizontal_margin"            android:layout_marginRight="@dimen/activity_horizontal_margin"            android:layout_marginTop="@dimen/activity_vertical_margin"            android:text="@string/title_home"            android:visibility="gone" />    </FrameLayout>    <android.support.v4.view.ViewPager        android:id="@+id/vp_content"        android:layout_width="match_parent"        android:layout_height="0dp"        android:layout_weight="1"        android:visibility="gone">    </android.support.v4.view.ViewPager>    <android.support.design.widget.BottomNavigationView        android:id="@+id/navigation"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_gravity="bottom"        android:background="?android:attr/windowBackground"        app:menu="@menu/navigation" /></LinearLayout>

MainActivity代码：

import android.os.Bundle;import android.support.annotation.NonNull;import android.support.design.widget.BottomNavigationView;import android.support.v4.app.Fragment;import android.support.v7.app.AppCompatActivity;import android.view.MenuItem;import android.widget.FrameLayout;import android.widget.TextView;import com.example.administrator.tablayout.fragment.BlankFragment;import com.example.administrator.tablayout.fragment.FragmentOne;import com.example.administrator.tablayout.fragment.FragmentTwo;import com.example.administrator.tablayout.fragment.ItemFragment;import com.example.administrator.tablayout.fragment.PlusOneFragment;public class MainActivity extends AppCompatActivity {    private TextView mTextMessage;    private BlankFragment blankFragment;    private ItemFragment itemFragment;    private PlusOneFragment plusOneFragment;    private FrameLayout fl;    private Fragment[] fragments;    private int lastShowFragment = 0;    private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener            = new BottomNavigationView.OnNavigationItemSelectedListener() {        @Override        public boolean onNavigationItemSelected(@NonNull MenuItem item) {            switch (item.getItemId()) {                case R.id.navigation_home:                    if (lastShowFragment != 0) {                        switchFrament(lastShowFragment, 0);                        lastShowFragment = 0;                    }                    return true;                case R.id.navigation_dashboard:                    if (lastShowFragment != 1) {                        switchFrament(lastShowFragment, 1);                        lastShowFragment = 1;                    }                    return true;                case R.id.navigation_notifications:                    if (lastShowFragment != 2) {                        switchFrament(lastShowFragment, 2);                        lastShowFragment = 2;                    }                    return true;            }            return false;        }    };    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        fl = (FrameLayout) findViewById(R.id.content);        mTextMessage = (TextView) findViewById(R.id.message);        BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);        navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);        initFragments();    }    /**     * 切换Fragment     *     * @param lastIndex 上个显示Fragment的索引     * @param index     需要显示的Fragment的索引     */    public void switchFrament(int lastIndex, int index) {        android.support.v4.app.FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();        transaction.hide(fragments[lastIndex]);        if (!fragments[index].isAdded()) {            transaction.add(R.id.content, fragments[index]);        }        transaction.show(fragments[index]).commitAllowingStateLoss();    }    private void initFragments() {        FragmentOne one = new FragmentOne();        FragmentTwo one2 = new FragmentTwo();        FragmentOne one3 = new FragmentOne();        fragments = new Fragment[]{one, one2, one3};        lastShowFragment = 0;        getSupportFragmentManager()                .beginTransaction()                .add(R.id.content, one)                .show(one)                .commit();    }}

over很简单。