Android使用BottomNavigationBar实现底部导航栏

compile ‘com.ashokvarma.android:bottom-navigation-bar:0.9.5'

 <com.ashokvarma.bottomnavigation.BottomNavigationBar android:layout_gravity="bottom" android:id="@+id/bottom_navigation_bar" android:layout_width="match_parent" android:layout_height="wrap_content"/>

BottomNavigationBar bottomNavigationBar = (BottomNavigationBar) findViewById(R.id.bottom_navigation_bar); bottomNavigationBar  .addItem(new BottomNavigationItem(R.drawable.ic_home_white_24dp, "Home"))  .addItem(new BottomNavigationItem(R.drawable.ic_book_white_24dp, "Books"))  .addItem(new BottomNavigationItem(R.drawable.ic_music_note_white_24dp, "Music"))  .addItem(new BottomNavigationItem(R.drawable.ic_tv_white_24dp, "Movies & TV"))  .addItem(new BottomNavigationItem(R.drawable.ic_videogame_asset_white_24dp, "Games"))  .initialise();

 bottomNavigationBar.setTabSelectedListener(new BottomNavigationBar.OnTabSelectedListener(){  @Override  public void onTabSelected(int position) {  }  @Override  public void onTabUnselected(int position) {]  }  @Override  public void onTabReselected(int position) {  } });

package com.android.xiaobai;  import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentTransaction; import android.support.v7.app.AppCompatActivity; import android.util.Log;  import com.ashokvarma.bottomnavigation.BottomNavigationBar; import com.ashokvarma.bottomnavigation.BottomNavigationItem;  import java.util.ArrayList;  import fragment.ContactsFragment; import fragment.DongtaiFragment; import fragment.MsgFragment;  /**  * Created by xiaobai on 2018/1/31/031.  */  public class MessageActivity extends AppCompatActivity implements BottomNavigationBar.OnTabSelectedListener {  private ArrayList<Fragment> fragments;  private BottomNavigationBar bottomNavigationBar;  private MsgFragment msgFragment;  private ContactsFragment contactsFragment;  private DongtaiFragment dongtaiFragment;  private FragmentManager fragmentManager;  private FragmentTransaction transaction;  int lastSelectedPosition = 0;   @Override  protected void onCreate(@Nullable Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activty_message);   bottomNavigationBar = findViewById(R.id.bottom_navigation_bar);  init();  }   private void init() {  //要先设计模式后再添加图标！  //设置按钮模式 MODE_FIXED表示固定 MODE_SHIFTING表示转移  bottomNavigationBar.setMode(BottomNavigationBar.MODE_FIXED);  //设置背景风格  // BACKGROUND_STYLE_STATIC表示静态的  //BACKGROUND_STYLE_RIPPLE表示涟漪的，也就是可以变化的 ，跟随setActiveColor里面的颜色变化  bottomNavigationBar.setBackgroundStyle(BottomNavigationBar.BACKGROUND_STYLE_RIPPLE);  //添加并设置图标、图标的颜色和文字  bottomNavigationBar   .addItem(new BottomNavigationItem(R.drawable.im_botton_message, "消息")).setActiveColor(R.color.blue)   .addItem(new BottomNavigationItem(R.drawable.im_botton_contacts, "联系人")).setActiveColor(R.color.red)   .addItem(new BottomNavigationItem(R.drawable.im_botton_dongtai, "动态")).setActiveColor(R.color.orign)   .setFirstSelectedPosition(lastSelectedPosition )   .initialise();   bottomNavigationBar.setTabSelectedListener(this);  setDefaultFragment();  }   //设置初始界面  private void setDefaultFragment() {  fragmentManager = getSupportFragmentManager();  transaction = fragmentManager.beginTransaction();  transaction.replace(R.id.layFrame, MsgFragment.newInstance("消息"));  transaction.commit();  }   @Override  public void onTabSelected(int position) {  fragmentManager = getSupportFragmentManager();  transaction = fragmentManager.beginTransaction();  switch (position) {   case 0:   if (msgFragment == null) {    msgFragment = MsgFragment.newInstance("消息");   }   transaction.replace(R.id.layFrame, msgFragment);   break;   case 1:   if (contactsFragment == null) {    contactsFragment = ContactsFragment.newInstance("联系人");   }   transaction.replace(R.id.layFrame, contactsFragment);   break;   case 2:   if (dongtaiFragment == null) {    dongtaiFragment = DongtaiFragment.newInstance("动态");   }   transaction.replace(R.id.layFrame, dongtaiFragment);   break;   default:   break;  }  // 事务提交  transaction.commit();  }   @Override  public void onTabUnselected(int position) {  Log.d("dongtaiFragment", "onTabUnselected() called with: " + "position = [" + position + "]");  }   @Override  public void onTabReselected(int position) {   } } 

package fragment;  import android.os.Bundle; import android.support.annotation.Nullable; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView;  import com.android.xiaobai.R;  /**  * Created by xiaobai on 2018/1/31/031.  */  public class MsgFragment extends BaseFragment {  /**  * 标志位，标志已经初始化完成  */  private boolean isPrepared;  /**  * 是否已被加载过一次，第二次就不再去请求数据了  */  private boolean mHasLoadedOnce;  TextView textView;  @Nullable  @Override  public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {  if (mView == null) {   // 需要inflate一个布局文件 填充Fragment   mView = inflater.inflate(R.layout.fragment_msg, container, false);   initView();   isPrepared = true; // 实现懒加载   lazyLoad();  }  //缓存的mView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mView已经有parent的错误。  ViewGroup parent = (ViewGroup) mView.getParent();  if (parent != null) {   parent.removeView(mView);  }   return mView;  }  /**  * 初始化控件  */  private void initView() {   }   @Override  public void lazyLoad() {  if (!isPrepared || !isVisible || mHasLoadedOnce) {   return;  }  //填充各控件的数据  mHasLoadedOnce = true;  }  public static MsgFragment newInstance(String param1) {  MsgFragment fragment = new MsgFragment();  Bundle args = new Bundle();  args.putString("agrs1", param1);  fragment.setArguments(args);  return fragment;  } } 

<?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=".MessageActivity">   <FrameLayout  android:id="@+id/layFrame"  android:layout_width="match_parent"  android:layout_height="0dp"  android:layout_weight="1" />   <com.ashokvarma.bottomnavigation.BottomNavigationBar  android:id="@+id/bottom_navigation_bar"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:layout_gravity="bottom" /> </LinearLayout> 

package fragment;  import android.support.v4.app.Fragment; import android.view.View;   /**  * Created by xiaobai on 2018/1/31/031.  */  public abstract class BaseFragment extends Fragment {  /**  * Fragment当前状态是否可见  */  public boolean isVisible;   /**  * inflate布局文件 返回的view  */  public View mView;   /**  * 简化 findViewById  *  * @param viewId  * @param <T>  * @return  */  protected <T extends View> T find(int viewId) {  return (T) mView.findViewById(viewId);  }   /**  * setUserVisibleHint是在onCreateView之前调用的  * 设置Fragment可见状态  */  @Override  public void setUserVisibleHint(boolean isVisibleToUser) {  super.setUserVisibleHint(isVisibleToUser);  /**   * 判断是否可见   */  if (getUserVisibleHint()) {   isVisible = true;   onVisible();  } else {   isVisible = false;   onInvisible();  }  }   /**  * 可见  */  private void onVisible() {  lazyLoad();  }   /**  * 不可见  */  private void onInvisible() {  }   /**  * 延迟加载  * 子类必须重写此方法  */  public abstract void lazyLoad(); }