起始页+Fragment 简单综合项目weixin48633671的博客-

起始页+Fragment 简单综合项目

起始页+Fragment +List View
1.首选确认需求 再进行书写
(1) 起始页 +页面跳转到主页面

 // 首选前端页面控件 获取到 后台 private ViewPager vpPaget2; private TextView tvText; // 适配器 Fragment的集合 在里面存入 想要在 起始页显示的 Fragment private ArrayList<Fragment> totalist=new ArrayList<>(); // MyAdapter2  自定义适配器  private  MyAdapter2 myAdapter2; private FragmentTransaction transaction; private FragmentManager manager; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_welcom);         vpPaget2 = findViewById(R.id.vp_paget2);         tvText = findViewById(R.id.tv_text);           totalist.add(new MyFragmentChildOne());         totalist.add(new MyFragmentChildTwo());         totalist.add(new MyFragmentChildThree());         myAdapter2=new MyAdapter2(getSupportFragmentManager(),totalist);        vpPaget2.setAdapter(myAdapter2);        vpPaget2.setOnPageChangeListener(new ViewPager.OnPageChangeListener() { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageSelected(int position) { if (position==totalist.size()-1){ // 使用CountDownTimer 进行计时并且   new CountDownTimer(3000,1000) { @SuppressLint("SetTextI18n") @Override public void onTick(long l) { // 当CountDownTimer 执行一次 进行一次 方法                              tvText.setText("倒计时"+l/1000+"秒"); } @Override public void onFinish() { //  当三次读秒结束 进行页面跳转                              Intent intent = new Intent(WelcomActivity.this, MainActivity.class); startActivity(intent); // 最后 finish 关闭当前 页面 finish(); } }.start(); } } @Override public void onPageScrollStateChanged(int state) { } }); } } 

MyAdapter2 自定义适配器 适配器书写方法

public class MyAdapter2 extends FragmentPagerAdapter { //声明集合 通过构造赋值  private ArrayList<Fragment> totalist; //FragmentManager  调用getSupportFragmentManager() 进行赋值 public MyAdapter2(@NonNull FragmentManager fm, ArrayList<Fragment> totalist) { super(fm); this.totalist = totalist; } //返回 postion位置的 Fegment @NonNull @Override public Fragment getItem(int position) { return totalist.get(position); } //返回 feagment的总数 @Override public int getCount() { return totalist.size(); } } 

主页面的书写

<?xml version="1.0" encoding="utf-8"?> <RelativeLayout 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"     tools:context=".MainActivity">     <FrameLayout         android:id="@+id/myFragment"         android:layout_width="match_parent"         android:layout_height="match_parent"/>     <RadioGroup         android:id="@+id/radio_button"         android:layout_width="match_parent"         android:layout_height="70dp"         android:orientation="horizontal"         android:layout_alignParentBottom="true"         >         <RadioButton             android:id="@+id/index"             android:layout_width="0dp"             android:layout_height="match_parent"             android:layout_weight="1"             android:button="@null"             android:text="首页"             android:gravity="center"             android:checked="true"             android:drawableTop="@mipmap/ye"             android:paddingTop="5dp"             />         <RadioButton             android:id="@+id/photos"             android:layout_width="0dp"             android:layout_height="match_parent"             android:layout_weight="1"             android:button="@null"             android:text="图库"             android:gravity="center"             android:checked="true"             android:drawableTop="@mipmap/hm"             android:paddingTop="5dp"             />         <RadioButton             android:id="@+id/finds"             android:layout_width="0dp"             android:layout_height="match_parent"             android:layout_weight="1"             android:button="@null"             android:text="首页"             android:gravity="center"             android:checked="true"             android:drawableTop="@mipmap/search"             android:paddingTop="5dp"             />         <RadioButton             android:id="@+id/linkman"             android:layout_width="0dp"             android:layout_height="match_parent"             android:layout_weight="1"             android:button="@null"             android:text="消息"             android:gravity="center"             android:drawableTop="@mipmap/wechat"             android:paddingTop="5dp"             />         <RadioButton             android:id="@+id/discover"             android:layout_width="0dp"             android:layout_height="match_parent"             android:layout_weight="1"             android:button="@null"             android:text="我的"             android:gravity="center"             android:drawableTop="@mipmap/post"             android:paddingTop="5dp"             />     </RadioGroup>     <TextView         android:id="@+id/text_view"         android:layout_width="match_parent"         android:layout_height="50dp"         android:textSize="20sp"         android:textColor="#ffffff"         android:layout_above="@+id/radio_button"         /> </RelativeLayout> 

主页面的 核心代码

// 五个页面的 显示转换 private void initView() {         myFragment = findViewById(R.id.myFragment);         radioButton = findViewById(R.id.radio_button);         index = findViewById(R.id.index);         photos = findViewById(R.id.photos);         finds = findViewById(R.id.finds);         linkman = findViewById(R.id.linkman);         discover = findViewById(R.id.discover);         textView = findViewById(R.id.text_view);             one=new MyFragmentOne();             two=new MyFragmentTwo();             three=new MyFragmentThree();             four=new MyFragmentFour();             find=new MyFragmentFind(); getSupportFragmentManager() .beginTransaction() .add(R.id.myFragment,one) .add(R.id.myFragment,two) .add(R.id.myFragment,three) .add(R.id.myFragment,four) .add(R.id.myFragment,find) .commit();         radioButton.setOnCheckedChangeListener ( new RadioGroup.OnCheckedChangeListener ( ) { @Override public void onCheckedChanged(RadioGroup group , int checkedId) { switch (checkedId) { case R.id.index: getSupportFragmentManager() .beginTransaction() .replace(R.id.myFragment,find).commit(); break; case R.id.finds:                         getSupportFragmentManager () .beginTransaction () .replace(R.id.myFragment,one) .commit (); break; case R.id.linkman:                         getSupportFragmentManager () .beginTransaction () .replace(R.id.myFragment,two) .commit (); break; case R.id.discover:                         getSupportFragmentManager () .beginTransaction () .replace(R.id.myFragment,three) .commit (); break; case R.id.photos: getSupportFragmentManager() .beginTransaction() .replace(R.id.myFragment,four).commit(); break; } } } ); } } 

页面中嵌套 tablayout

 public class MyFragmentFind extends Fragment { private TabLayout tlLayout; private ViewPager vpPager; private ArrayList<String> titles=new ArrayList<>(); private ArrayList<Fragment> totalist=new ArrayList<>(); private MyFragmentChildOne one=new MyFragmentChildOne(); private MyFragmentChildTwo two=new MyFragmentChildTwo(); private MyFragmentChildThree three=new MyFragmentChildThree(); private MyFragmentList   list=new MyFragmentList(); private MyFragmentParger parger; @Nullable @Override public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {         View view=inflater.inflate(R.layout.fragment_tab,null);         tlLayout =view.findViewById(R.id.tl_layout);         vpPager = view.findViewById(R.id.vp_pager); initDatas(); return view; } private void initDatas() {          titles.add("推荐");         titles.add("男士发型打理");         titles.add("热发型");         titles.add("编发教程");         totalist.add(list);         totalist.add(one);         totalist.add(two);         totalist.add(three);         parger=new MyFragmentParger(getChildFragmentManager(),totalist,titles);         vpPager.setAdapter(parger);         tlLayout.setupWithViewPager(vpPager); } } 

页面中嵌套 tablayout 页面书写(注意 : 要导入依赖)
依赖:
implementation ‘com.android.support:design:28.0.0’

<?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">     <com.google.android.material.tabs.TabLayout         android:layout_width="match_parent"         android:layout_height="0dp"         android:layout_weight="0.8"         android:id="@+id/tl_layout"/>      <androidx.viewpager.widget.ViewPager         android:layout_width="match_parent"         android:layout_height="0dp"         android:layout_weight="9"         android:id="@+id/vp_pager"/> </LinearLayout> 

普通 Frgment 页面随意书写 每一个 frgment对应一个类
每个对应类 需要继承 Frgment 并且重写方法

 public class MyFragmentOne extends Fragment { private RadioGroup radioButton02; private MyFragmentChildOne childOne; private MyFragmentChildTwo childTwo; private MyFragmentChildThree childThree; private MyFragmentChildFour childFour; private MyFragmentChildFive childFive; @Nullable @Override public View onCreateView(@NonNull LayoutInflater inflater , @Nullable ViewGroup container , @Nullable Bundle savedInstanceState) {         View view = inflater.inflate ( R.layout.fragment_view01 , null );         childOne = new MyFragmentChildOne ( );         childTwo = new MyFragmentChildTwo ( );         childThree = new MyFragmentChildThree ( );         childFour = new MyFragmentChildFour ( );         childFive = new MyFragmentChildFive ( ); // childOne.setMessage ( childThree );          MainActivity activity = (MainActivity) getActivity ( ); //childThree.setMessage (activity.three );          getChildFragmentManager ( ) .beginTransaction ( ) .add ( R.id.myFragment_02 , childTwo ) .add ( R.id.myFragment_02 , childThree ) .add ( R.id.myFragment_02 , childFour ) .add ( R.id.myFragment_02 , childFive ) .add ( R.id.myFragment_02 , childOne ) .hide ( childTwo ) .hide ( childThree ) .hide ( childFour ) .hide ( childFive ) .show ( childOne ) .commit ( );          radioButton02 = (RadioGroup) view.findViewById ( R.id.radio_button_02 ); return view; } @Override public void onActivityCreated(@Nullable Bundle savedInstanceState) { super.onActivityCreated ( savedInstanceState ); //        final MainActivity activity = (MainActivity) getActivity ( );          radioButton02.setOnCheckedChangeListener ( new RadioGroup.OnCheckedChangeListener ( ) { @Override public void onCheckedChanged(RadioGroup group , int checkedId) { switch (checkedId) { case R.id.button_all:                         getChildFragmentManager ( ) .beginTransaction ( ) .hide ( childTwo ) .hide ( childThree ) .hide ( childFour ) .hide ( childFive ) .show ( childOne ) .commit ( ); break; case R.id.button_video:                         getChildFragmentManager ( ) .beginTransaction ( ) .hide ( childOne ) .hide ( childThree ) .hide ( childFour ) .hide ( childFive ) .show ( childTwo ) .commit ( ); break; case R.id.button_pic:                          getChildFragmentManager ( ) .beginTransaction ( ) .hide ( childOne ) .hide ( childTwo ) .hide ( childThree ) .hide ( childFive ) .show ( childFour) .commit ( ); break; case R.id.button_voice:                         getChildFragmentManager ( ) .beginTransaction ( ) .hide ( childOne ) .hide ( childTwo ) .hide ( childFour ) .hide ( childFive ) .show ( childThree) .commit ( ); break; case R.id.button_dz:                         getChildFragmentManager ( ) .beginTransaction ( ) .hide ( childOne ) .hide ( childTwo ) .hide ( childThree ) .hide ( childFour ) .show (childFive ) .commit ( ); break; } } } ); } } 

fegment中 如何书写 ListView

public class MyFragmentList extends Fragment { private ListView iv_list; // 放入json 数据的 网址  private   String urlString="https://www.qubaobei.com/ios/cf/dish_list.php?stage_id=1&limit=10&page=1"; private   MyAdapter myAdapter; // json数据解析后的类 创建集合  private  List<JavaBean.DataBean> totalist=new ArrayList<>(); @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); } @Nullable @Override public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {         View view=inflater.inflate(R.layout.fragment_list,null); new JsonAsyntck().execute(urlString);         iv_list=view.findViewById(R.id.iv_list);         myAdapter=new MyAdapter(getActivity().getBaseContext(),totalist);         iv_list.setAdapter(myAdapter);         iv_list.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {                 Toast.makeText(getActivity().getBaseContext(), "短点击事件", Toast.LENGTH_SHORT).show(); } });         iv_list.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() { @Override public boolean onItemLongClick(AdapterView<?> adapterView, View view, int i, long l) {                 Toast.makeText(getActivity().getBaseContext(), "长点事件", Toast.LENGTH_SHORT).show(); return false; } }); return view; } public class JsonAsyntck extends AsyncTask<String,Void,List<JavaBean.DataBean>> { @Override protected List<JavaBean.DataBean> doInBackground(String... strings) { try {                 URL url = new URL(strings[0]);                 HttpURLConnection conn = (HttpURLConnection) url.openConnection();                  conn.setRequestMethod("GET");                 conn.connect(); if (conn.getResponseCode()==200){                     InputStream is = conn.getInputStream();                     ByteArrayOutputStream byso = new ByteArrayOutputStream(); int len=0; byte[] bs = new byte[1024]; while ((len=is.read(bs))!=-1){                         byso.write(bs,0,len); }                     String json = byso.toString();                      Gson gson = new Gson();                     JavaBean javaBean = gson.fromJson(json, JavaBean.class);                     List<JavaBean.DataBean> data = javaBean.getData(); return data; } } catch (MalformedURLException e) {                 e.printStackTrace(); } catch (IOException e) {                 e.printStackTrace(); } return null; } @Override protected void onPostExecute(List<JavaBean.DataBean> dataBeans) { super.onPostExecute(dataBeans); if (dataBeans!=null){                 totalist.addAll(dataBeans);                 myAdapter.notifyDataSetChanged(); } } } } 

ListView需要适配器才可以 显示内容 适配器 书写

 public class MyAdapter extends BaseAdapter { private Context context; private List<JavaBean.DataBean> totalist; private LayoutInflater layoutInflater; public MyAdapter(Context context, List<JavaBean.DataBean> totalist) { this.context = context; this.totalist = totalist; this.layoutInflater=LayoutInflater.from(context); } @Override public int getCount() { return totalist.size(); } @Override public Object getItem(int position) { return totalist.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) {         ViewHoder viewHoder=null; if (convertView==null){             viewHoder=new ViewHoder();             convertView=layoutInflater.inflate(R.layout.item_list,null);             viewHoder.iv_item=convertView.findViewById(R.id.iv_item);             viewHoder.tv_item=convertView.findViewById(R.id.tv_item);               convertView.setTag(viewHoder); }else {             viewHoder= (ViewHoder) convertView.getTag(); }          JavaBean.DataBean dataBean = totalist.get(position);         String title = dataBean.getTitle();         String pic = dataBean.getPic();          viewHoder.tv_item.setText(title);         Picasso.with(context).load(pic).into(viewHoder.iv_item); return convertView; } class ViewHoder{ private ImageView iv_item; private TextView tv_item; } }