通用型的底部导航栏示例

废话不多说，上图：

几乎所有的应用app都有这么一块导航栏。现在把最省心的一种写法放到这里，自己的轮子，用着放心。

关键代码如下：

BottomAdapter.java

  1 package com.example.gc_hank.evolutionpro.ui.bottom;
  2 
  3 import android.app.Activity;
  4 import android.content.Context;
  5 import android.graphics.drawable.Drawable;
  6 import android.support.annotation.NonNull;
  7 import android.support.v7.widget.RecyclerView;
  8 import android.util.DisplayMetrics;
  9 import android.view.LayoutInflater;
 10 import android.view.View;
 11 import android.view.ViewGroup;
 12 import android.view.WindowManager;
 13 import android.widget.ImageView;
 14 import android.widget.LinearLayout;
 15 import android.widget.TextView;
 16 
 17 import com.example.gc_hank.evolutionpro.R;
 18 
 19 import java.util.List;
 20 
 21 import butterknife.BindView;
 22 import butterknife.ButterKnife;
 23 
 24 /**
 25  * 底部导航栏专用RecyclerView.Adapter示例
 26  */
 27 public class BottomAdapter extends RecyclerView.Adapter {
 28 
 29     private List<TabTitle> mTitleObjectList;//
 30     private int mSelectedPosition = 0;
 31     private OnItemClickListener onItemClickListener;
 32 
 33     /**
 34      * 对外接口
 35      */
 36     public interface OnItemClickListener {
 37         void onItemClick(int position);
 38     }
 39 
 40     private Activity mActivity;
 41     private int itemWidth;
 42 
 43     public BottomAdapter(Activity activity, List<TabTitle> titleObjectList) {
 44         mActivity = activity;
 45         mTitleObjectList = titleObjectList;
 46     }
 47 
 48     @NonNull
 49     @Override
 50     public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
 51         View view = LayoutInflater.from(mActivity).inflate(R.layout.adapter_list_item_bottom_title, null);
 52         initItemWidth();
 53         return new BottomHolder(view);
 54     }
 55 
 56     @Override
 57     public void onBindViewHolder(@NonNull RecyclerView.ViewHolder viewHolder, final int position) {
 58         BottomHolder bHolder = (BottomHolder) viewHolder;
 59 
 60         int titleNameId = mTitleObjectList.get(position).getTitleName();
 61         Drawable titleIconDrawable = mTitleObjectList.get(position).getDrawable();
 62 
 63         bHolder.tvTitle.setTextColor(mActivity.getResources().getColorStateList(mTitleObjectList.get(position).getTextColorStateList()));
 64         bHolder.tvTitle.setText(mActivity.getResources().getString(titleNameId));
 65 
 66         bHolder.ivIcon.setImageDrawable(titleIconDrawable);
 67 
 68         bHolder.llMain.getLayoutParams().width = itemWidth;
 69         bHolder.llMain.getLayoutParams().height = (int) mActivity.getResources().getDimension(R.dimen.height_b);
 70 
 71         bHolder.llMain.requestLayout();//由于要强制等分，所以，要重新布局一下，调整宽高
 72 
 73         if (mSelectedPosition == position) {// 如果当前tab被选中了
 74             bHolder.ivIcon.setSelected(true);
 75             bHolder.tvTitle.setSelected(true);
 76         } else {
 77             bHolder.ivIcon.setSelected(false);
 78             bHolder.tvTitle.setSelected(false);
 79         }
 80 
 81         bHolder.llMain.setOnClickListener(new View.OnClickListener() {
 82             @Override
 83             public void onClick(View v) {
 84                 setSelection(position);//先改变当前的item的选中情况
 85                 if (null != onItemClickListener)
 86                     onItemClickListener.onItemClick(position);//再执行外界传入的点击事件
 87             }
 88         });
 89     }
 90 
 91     /**
 92      * 让每一个item等分
 93      */
 94     private void initItemWidth() {
 95         WindowManager windowManager = (WindowManager) mActivity.getSystemService(Context.WINDOW_SERVICE);// 得到当前屏幕的宽度，然后分成getItemCount等分,让每个item平均分配
 96         DisplayMetrics metrics = new DisplayMetrics();
 97         windowManager.getDefaultDisplay().getMetrics(metrics);
 98         int w = metrics.widthPixels;//这就是宽度像素值
 99         itemWidth = w / getItemCount();
100     }
101 
102     @Override
103     public int getItemCount() {
104         return mTitleObjectList == null ? 0 : mTitleObjectList.size();
105     }
106 
107     @Override
108     public int getItemViewType(int position) {
109         return super.getItemViewType(position);
110     }
111 
112     class BottomHolder extends RecyclerView.ViewHolder {
113 
114         @BindView(R.id.tv_title)
115         TextView tvTitle;
116         @BindView(R.id.iv_icon)
117         ImageView ivIcon;
118         @BindView(R.id.ll_main)
119         LinearLayout llMain;
120 
121         public BottomHolder(@NonNull View itemView) {
122             super(itemView);
123             ButterKnife.bind(this, itemView);
124         }
125     }
126 
127     //```````````以下全都是对外接口····················//
128     public void setSelection(int position) {
129         this.mSelectedPosition = position;
130         notifyDataSetChanged();
131     }
132 
133     public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
134         this.onItemClickListener = onItemClickListener;
135     }
136 
137 
138 }

View Code

TabTitle.java

 1 package com.example.gc_hank.evolutionpro.ui.bottom;
 2 
 3 import android.graphics.drawable.StateListDrawable;
 4 
 5 public class TabTitle {
 6     private int titleName;
 7     private int textColorStateList;
 8     private StateListDrawable drawable;
 9 
10     /**
11      * 底部导航栏配置类
12      *
13      * @param titleName          标题text
14      * @param textColorStateList 标题颜色selector
15      * @param drawable           标题icon 的selector
16      */
17     public TabTitle(int titleName, int textColorStateList, StateListDrawable drawable) {
18         this.titleName = titleName;
19         this.drawable = drawable;
20         this.textColorStateList = textColorStateList;
21     }
22 
23     public int getTitleName() {
24         return titleName;
25     }
26 
27     public StateListDrawable getDrawable() {
28         return drawable;
29     }
30 
31     public int getTextColorStateList() {
32         return textColorStateList;
33     }
34 
35 
36 }

View Code

MainActivity.java

package com.example.gc_hank.evolutionpro.ui;

import android.graphics.drawable.StateListDrawable;
import android.os.Bundle;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;

import com.example.gc_hank.evolutionpro.R;
import com.example.gc_hank.evolutionpro.ui.bottom.BottomAdapter;
import com.example.gc_hank.evolutionpro.ui.bottom.TabTitle;

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

import butterknife.BindView;
import butterknife.ButterKnife;

public class MainActivity extends AppCompatActivity {

    @BindView(R.id.rv_bottom)
    RecyclerView mRvBottom;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);
        initBottom();
    }

    private void initBottom() {
        LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
        linearLayoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);
        mRvBottom.setLayoutManager(linearLayoutManager);

        final BottomAdapter adapter = new BottomAdapter(this, getSetting());
        adapter.setOnItemClickListener(new BottomAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(int position) {
                adapter.setSelection(position);
                //TODO 并且这里要切换Fragment
                Log.d("onItemClickTag", "" + position);
            }
        });
        mRvBottom.setAdapter(adapter);
    }

    //
    private List<TabTitle> getSetting() {
        List<TabTitle> titleObjectList = new ArrayList<>();
        titleObjectList.add(new TabTitle(R.string.tag_name_home, R.color.home_tab_text_selector, getStateListDrawable(R.mipmap.a_tabbar_home, R.mipmap.a_tabbar_home_p)));
        titleObjectList.add(new TabTitle(R.string.tag_name_quote, R.color.home_tab_text_selector, getStateListDrawable(R.mipmap.a_tabbar_market, R.mipmap.a_tabbar_market_p)));
        titleObjectList.add(new TabTitle(R.string.tag_name_deal, R.color.home_tab_text_selector, getStateListDrawable(R.mipmap.a_tabbar_trade, R.mipmap.a_tabbar_trade_p)));
        titleObjectList.add(new TabTitle(R.string.tag_name_mine, R.color.home_tab_text_selector, getStateListDrawable(R.mipmap.a_tabbar_me, R.mipmap.a_tabbar_me_p)));
        return titleObjectList;
    }

    /**
     * 返回一个Drawable对象，可以根据selected状态改变 图标
     *
     * @param normalIcon
     * @param selectedIcon
     * @return
     */
    private StateListDrawable getStateListDrawable(int normalIcon, int selectedIcon) {
        StateListDrawable drawable = new StateListDrawable();
        drawable.addState(new int[]{android.R.attr.state_selected}, ContextCompat.getDrawable(this, selectedIcon));//选中之后的drawable
        drawable.addState(new int[]{}, ContextCompat.getDrawable(this, normalIcon));//正常情况下的drawable
        return drawable;
    }
}

View Code

然后是资源文件：

home_tab_text_selector.xml:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="#2A60F5" android:state_checked="true" />
    <item android:color="#2A60F5" android:state_selected="true" />
    <item android:color="#8D939B" />
</selector>

View Code

最后给出github的地址：

https://github.com/18598925736/CommonBottomBar

下载可直接运行

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原文地址：https://www.cnblogs.com/hankzhouAndroid/p/10110125.html