Android使用FragmentTabHost实现底部导航栏切换卡

痛定思痛。 2022-11-25 11:39 228阅读 0赞

# 一、编写布局 #

编写activity\_main.xml 布局

<?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:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        tools:context=".MainActivity">
    
        <FrameLayout android:id="@+id/contentLayout"
            android:layout_width="match_parent"
            android:layout_height="0dp"
            tools:ignore="Suspicious0dp"
            android:layout_weight="1">
    
        </FrameLayout>
    
        <androidx.fragment.app.FragmentTabHost
            android:id="@android:id/tabhost"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:background="#ffffff">
    
            <FrameLayout android:id="@android:id/tabcontent"
                android:layout_height="0dp"
                android:layout_width="0dp"
                />
    
        </androidx.fragment.app.FragmentTabHost>
    
    </LinearLayout>

编写footer\_tabs.xml *(这个布局相当于底部导航栏的一个图标和对应标题的组合体，底部导航栏一共5个，那么这个布局文件就复用了5次)*

<?xml version="1.0" encoding="utf-8"?>
    
        <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical"
            android:padding="5dp"
            android:background="#F6F6F6"
            >
            <ImageView
                android:id="@+id/ivImg"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="false"
                android:layout_alignParentTop="true"
                />
    
            <TextView
                android:id="@+id/tvTab"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textColor="#AEAEAE"
                android:text="新闻"
                android:layout_marginTop="2dp"
                android:paddingLeft="0dp"/>
    
        </LinearLayout>

# 二、在drawable添加10张图片 #

[https://www.iconfont.cn/][https_www.iconfont.cn]    此网站可以搜索并下载很好看的图标，颜色、大小也可以自定义

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1hlb25fQ0M_size_16_color_FFFFFF_t_70][]

我命名图片名称为：

foot_fond_normal.png
    foot_found_light.png
    foot_news_light.png
    foot_news_normal.png
    foot_out_light.png
    foot_out_normal.png
    foot_read_light.png
    foot_read_normal.png
    foot_vdio_light.png
    foot_vdio_normal.png

# 三、添加颜色配置 #

在values文件夹的colors.xml文件，添加下面两种颜色

<color name="read">#ff0000</color>
        <color name="foot_txt_gray">#AEAEAE</color>

# 四、编写TabDb类 #

这个类用来指定底部导航栏的图标路径、标题文字、各个Fragment页面对应的类

public class TabDb {
    	public static String[] getTabsTxt(){
    		String[] tabs={"新闻","读物","媒体","发现","我的"};
    		return tabs;
    	}
    	public static int[] getTabsImg(){
    		int[] ids={R.drawable.foot_news_normal,R.drawable.foot_read_normal,R.drawable.foot_vdio_normal,R.drawable.foot_fond_normal,R.drawable.foot_out_normal};
    		return ids;
    	}
    	public static int[] getTabsImgLight(){
    		int[] ids={R.drawable.foot_news_light,R.drawable.foot_read_light,R.drawable.foot_vdio_light,R.drawable.foot_found_light,R.drawable.foot_out_light};
    		return ids;
    	}
    	public static Class[] getFragments(){
    		Class[] clz={NewsFragment.class,ReadFragment.class,VideoFragment.class,FoundFragment.class,OwnerFragment.class};
    		return clz;
    	}
    }

# 五、编写所有Fragment类 #

这5个Fragment是要展示数据的界面

FoundFragment  
NewsFragment  
OwnerFragment  
ReadFragment  
VideoFragment

public class FoundFragment extends Fragment {
    
        @Override
        public void onAttach(Context activity) {
            // TODO Auto-generated method stub
            super.onAttach(activity);
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            TextView tvTitle=new TextView(super.getActivity());
            tvTitle.setText("FoundFragment");
            tvTitle.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            tvTitle.setGravity(Gravity.CENTER);
            tvTitle.setTextSize(30);
            return tvTitle;
        }
    
        @Override
        public void setArguments(Bundle args) {
            // TODO Auto-generated method stub
            super.setArguments(args);
        }
    
    }

public class NewsFragment extends Fragment {
    
        @Override
        public void onAttach(Context activity) {
            // TODO Auto-generated method stub
            super.onAttach(activity);
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            TextView tvTitle=new TextView(super.getActivity());
            tvTitle.setText("NewsFragment");
            tvTitle.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            tvTitle.setGravity(Gravity.CENTER);
            tvTitle.setTextSize(30);
            return tvTitle;
        }
    
        @Override
        public void setArguments(Bundle args) {
            // TODO Auto-generated method stub
            super.setArguments(args);
        }
    
    }

public class OwnerFragment extends Fragment {
    
        @Override
        public void onAttach(Context activity) {
            // TODO Auto-generated method stub
            super.onAttach(activity);
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            TextView tvTitle=new TextView(super.getActivity());
            tvTitle.setText("OwnerFragment");
            tvTitle.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            tvTitle.setGravity(Gravity.CENTER);
            tvTitle.setTextSize(30);
            return tvTitle;
        }
    
        @Override
        public void setArguments(Bundle args) {
            // TODO Auto-generated method stub
            super.setArguments(args);
        }
    
    }

public class ReadFragment extends Fragment {
    
        @Override
        public void onAttach(Context activity) {
            // TODO Auto-generated method stub
            super.onAttach(activity);
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            TextView tvTitle=new TextView(super.getActivity());
            tvTitle.setText("ReadFragment");
            tvTitle.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            tvTitle.setGravity(Gravity.CENTER);
            tvTitle.setTextSize(30);
            return tvTitle;
        }
    
        @Override
        public void setArguments(Bundle args) {
            // TODO Auto-generated method stub
            super.setArguments(args);
        }
    
    }

public class VideoFragment extends Fragment {
    
        @Override
        public void onAttach(Context activity) {
            // TODO Auto-generated method stub
            super.onAttach(activity);
        }
    
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            TextView tvTitle=new TextView(super.getActivity());
            tvTitle.setText("VideoFragment");
            tvTitle.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            tvTitle.setGravity(Gravity.CENTER);
            tvTitle.setTextSize(30);
            return tvTitle;
        }
    
        @Override
        public void setArguments(Bundle args) {
            // TODO Auto-generated method stub
            super.setArguments(args);
        }
    
    }

# 六、编写MainActivity #

public class MainActivity extends FragmentActivity implements TabHost.OnTabChangeListener {
    
        private FragmentTabHost tabHost;
        protected void onCreate(Bundle savedInstanceState){
    
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            //tabHost属于父元素，表示整个界面，找到布局文件的tabhost，然后赋值给tabHost，这样就可以用tabHost对象来操作布局了
            tabHost=(FragmentTabHost)super.findViewById(android.R.id.tabhost);
            //在tabHost创建FragmentLayout , contentLayout的id就是布局文件里面FragmentLayout的id，如果在布局文件FragmentLayout添加子元素，那么实际上相互切换的3个FragmentLayout都会被添加子元素
            tabHost.setup(this,super.getSupportFragmentManager(),R.id.contentLayout);
            //getTabWidget()方法表示获取切换卡，setDividerDrawable(null)表示没有分割线
            tabHost.getTabWidget().setDividerDrawable(null);
            //点击下面5个图标的时候会变色，就是setOnTabChangedListener(this)方法影响的，如果没有这个方法，那么点击图标不会变色
            tabHost.setOnTabChangedListener(this);
            initTab();
    
    
        }
        //initTab()方法表示没有点击图标的时候的初始状态
        private void initTab() {
            //tabs就是下面导航栏的“新闻”，“读物”，“媒体” 。。。的5个图标下面的文字，但是觉得不好看，就直接通过设置布局把文字隐藏了
            String tabs[]=TabDb.getTabsTxt();
            for(int i=0;i<tabs.length;i++){
                //https://www.cnblogs.com/littleby/p/5178736.html
                //TabHost相当于浏览器中分页的集合，而TabSpec则相当于浏览器中的每个分页。可以理解为TabHost就是放3个图标的长条区域的对象集合，TabSpec就是这个集合里面的每个对象
                //一个图标和下面一个文本加起来就属于一个TabSpec，可以理解为一个标签空间。tabs[i]只是将每个标签空间的名字设置为“新闻”，“读物”，“媒体” 。。。而已，这个可以随便设置。
                //setIndicator(View view)方法表示，把一些元素装进标签空间里面！
                TabHost.TabSpec tabSpec=tabHost.newTabSpec(tabs[i]).setIndicator(getTabView(i));
                //addTab()方法表示添加导航栏
                tabHost.addTab(tabSpec,TabDb.getFragments()[i],null);
                tabHost.setTag(i);
            }
        }
    
        private View getTabView(int idx) {
            //引入footer_tabs.xml布局，这个布局包含了导航栏的图片和文本，我这里通过设置布局文件参数把文本隐藏了
            View view= LayoutInflater.from(this).inflate(R.layout.footer_tabs,null);
    
            ((TextView)view.findViewById(R.id.tvTab)).setText(TabDb.getTabsTxt()[idx]);
            //下面的判断语句表示图标颜色的默认状态，第一个图标默认点亮，其他默认不点亮
            if(idx==0){
    
                ((TextView)view.findViewById(R.id.tvTab)).setTextColor(Color.RED);
                //设置为点亮的图标
                ((ImageView)view.findViewById(R.id.ivImg)).setImageResource(TabDb.getTabsImgLight()[idx]);
            }else{
                //设置为点不亮的图标
                ((ImageView)view.findViewById(R.id.ivImg)).setImageResource(TabDb.getTabsImg()[idx]);
            }
            return view;
        }
    
        //onTabChanged自带方法
        @Override
        public void onTabChanged(String tabId) {
            updateTab();
        }
    
        //点击图标就会调用updateTab()方法
        private void updateTab(){
            //TabWidget表示切换卡
            TabWidget tabw=tabHost.getTabWidget();
            for(int i=0;i<tabw.getChildCount();i++){
                View view=tabw.getChildAt(i);
                ImageView iv=(ImageView)view.findViewById(R.id.ivImg);
                if(i==tabHost.getCurrentTab()){
                    ((TextView)view.findViewById(R.id.tvTab)).setTextColor(Color.RED);
                    iv.setImageResource(TabDb.getTabsImgLight()[i]);
                }else{
                    ((TextView)view.findViewById(R.id.tvTab)).setTextColor(getResources().getColor(R.color.foot_txt_gray));
                    iv.setImageResource(TabDb.getTabsImg()[i]);
                }
    
            }
        }
    
    }

运行效果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1hlb25fQ0M_size_16_color_FFFFFF_t_70 1][]

[https_www.iconfont.cn]: https://www.iconfont.cn/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1hlb25fQ0M_size_16_color_FFFFFF_t_70]: /images/20221124/2f6618f4d7204b91be62c8db0ce93d75.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L1hlb25fQ0M_size_16_color_FFFFFF_t_70 1]: /images/20221124/050c75a9812a41b2859864a6f90ad72d.png