Bootstrap

Fragment动态加载案例

目录

MainActivity:

activity_main:

右边的菜列表   FoodFragment代码：

 food_menu:

food_item: 

左边的菜单栏：MenuFragment代码： 

fragment_menu: 

item:

在Activity中动态加载Fragment步骤

（1）、创建一个Fragment对象

（2）、获取FragmentManager的实例

（3）、开启FragmentTransaction事务

（4）、向Activity的布局器（一般为FrameLayout）中添加Fragment

（5）、通过commit()方法提交事务

案例：简易的点菜界面

效果图：    

MainActivity:

package com.example.test;

import androidx.appcompat.app.AppCompatActivity;

import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;

public class MainActivity extends AppCompatActivity {
    private FragmentTransaction beginTransaction;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // 1、创建Fragment对象
        FoodFragment foodFragment = new FoodFragment();
        MenuFragment menuFragment = new MenuFragment();
        // 2、获取FragmentManager的实例
        FragmentManager fm = getFragmentManager();
        // 3、开启FragmentTransaction事务
        beginTransaction = fm.beginTransaction();
        // 4、向Activity布局器添加两个Fragment
        beginTransaction.replace(R.id.foodcontent,foodFragment);
        beginTransaction.replace(R.id.menu,menuFragment);
        // 5、提交事务
        beginTransaction.commit();
    }
}

activity_main:

<?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="horizontal"
    tools:context=".MainActivity">

    <FrameLayout
        android:id="@+id/menu"
        android:layout_weight="1.5"
        android:layout_width="0dp"
        android:layout_height="match_parent">

    </FrameLayout>
    <FrameLayout
        android:id="@+id/foodcontent"
        android:layout_weight="3"
        android:layout_width="0dp"
        android:layout_height="match_parent">

    </FrameLayout>

</LinearLayout>

右边的菜列表   FoodFragment代码：

package com.example.test;

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;


import androidx.annotation.Nullable;

public class FoodFragment extends Fragment {
    // 主菜
    private int food_icons0[] = {R.drawable.malatang,R.drawable.xiaojidunmogu,R.drawable.jitui,R.drawable.jitui2};
    private String food_name0[] = {"麻辣烫","小鸡炖蘑菇","炸鸡腿","鸡腿"};
    // 青菜
    private int food_icons1[] = {R.drawable.qing,R.drawable.baicai};
    private String food_name1[] = {"青菜","白菜"};
    // 粥
    private int food_icons2[] = {R.drawable.luosifen,R.drawable.yuntun,R.drawable.baizhou,R.drawable.piduanshourouzhou,R.drawable.yumizhou};
    private String food_name2[] = {"螺蛳粉","云吞","白粥","皮蛋瘦肉粥","玉米粥"};
    // 汤
    private int food_icons3[] = {R.drawable.jitang,R.drawable.paigutang};
    private String food_name3[] = {"乌鸡汤","排骨汤"};



    private String food_evaluation[] = {"月售：999 好评度99%","月售：999 好评度99%","月售：999 好评度99%","月售：999 好评度99%","月售：999 好评度99%"};
    private String food_price[] = {"￥15.99","￥12.99","￥12.99","￥12.99","￥12.99"};
    private String food_choice[] = {"选规格","选规格","选规格","选规格","选规格"};
    private View mView;
    private ListView mListView;
    public MyAdapter mAdapter;
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
        mView = inflater.inflate(R.layout.food_menu,container,false);
        initView();

        return mView;
    }

    private void initView() {
        mListView = mView.findViewById(R.id.food_menu);
        mAdapter = new MyAdapter(0);
        mListView.setAdapter(mAdapter);
    }
    public void setType(int type){
        mAdapter = null;
        mAdapter = new MyAdapter(type);
        mListView.setAdapter(mAdapter);
    }


    private class MyAdapter extends BaseAdapter {
        private int TYPE;
        public MyAdapter (int type){
            TYPE = type;
        }
        @Override
        public int getCount() {
            switch (TYPE){
                case 0:
                    return food_icons0.length;
                case 1:
                    return food_icons1.length;
                case 2:
                    return food_icons2.length;
                case 3:
                return food_icons3.length;

                default:
                    return 2;
            }
        }

        @Override
        public Object getItem(int position) {

            switch (TYPE){
                case 0:
                    return food_icons0[position];
                case 1:
                    return food_icons1[position];
                case 2:
                    return food_icons2[position];
                case 3:
                    return food_icons3[position];

                default:
                    return 1;
            }
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            convertView = View.inflate(getActivity(),R.layout.food_item,null);
            TextView foodName = convertView.findViewById(R.id.food_name);
            TextView evaluates = convertView.findViewById(R.id.estimate);
            ImageView food_iv = convertView.findViewById(R.id.food_icon);
            TextView price = convertView.findViewById(R.id.food_price);
            TextView choice =convertView.findViewById(R.id.choice);

                evaluates.setText(food_evaluation[position]);
                price.setText(food_price[position]);
                choice.setText(food_choice[position]);



            switch (TYPE){
                case 0:
                    food_iv.setBackgroundResource(food_icons0[position]);
                    foodName.setText(food_name0[position]);
                    break;
                case 1:
                    food_iv.setBackgroundResource(food_icons1[position]);
                    foodName.setText(food_name1[position]);
                    break;
                case 2:
                    food_iv.setBackgroundResource(food_icons2[position]);
                    foodName.setText(food_name2[position]);
                    break;
                case 3:
                    food_iv.setBackgroundResource(food_icons3[position]);
                    foodName.setText(food_name3[position]);
                default:
                    food_iv.setBackgroundResource(food_icons0[position]);
                    foodName.setText(food_name0[position]);
            }
            return convertView;
        }
    }
}

 food_menu:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_height="match_parent">
    <ListView

        android:fadingEdge="vertical"
        android:divider="@color/white"
        android:id="@+id/food_menu"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"/>

</LinearLayout>

food_item: 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:orientation="horizontal"
    android:layout_height="match_parent">
    <ImageView

        android:id="@+id/food_icon"
        android:paddingTop="20dp"
        android:paddingLeft="10dp"
        android:layout_width="100dp"
        android:layout_height="80dp"
       />
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="100dp"
        android:orientation="vertical"
        >
        <TextView
            android:paddingLeft="10dp"
            android:id="@+id/food_name"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="卤蛋螺蛳粉"
            android:textColor="@color/black"
            android:textSize="18sp"
            />
        <TextView
            android:id="@+id/estimate"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="月售：999 好评度99%"
            android:textSize="10sp"
            android:paddingLeft="10dp"
            />
        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <TextView
                android:id="@+id/food_price"
                android:layout_width="100dp"
                android:layout_height="wrap_content"
                android:paddingLeft="10dp"
                android:text="￥20.05"
                android:textColor="#CD1E1E"
                android:textSize="15sp" />

            <TextView
                android:id="@+id/choice"
                android:background="#F8DF04"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:textSize="10sp"
                android:text="选规格" />
        </LinearLayout>

    </LinearLayout>

</LinearLayout>

左边的菜单栏：MenuFragment代码： 

package com.example.test;

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import androidx.annotation.Nullable;

public class MenuFragment extends Fragment {
    private String[] tips = {"推荐","折扣","进店必买","人气精选","店内招牌","热销单人餐","多人餐","加料区","饮料区","店内环境","有事联系"};
    private View mView;
    private ListView mListView;
    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
        mView = inflater.inflate(R.layout.fragment_menu,container,false);
        if(mView!=null){
            initView();
        }
        mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                FoodFragment foodFragment = (FoodFragment) (getActivity()).getFragmentManager().findFragmentById(R.id.foodcontent);
                foodFragment.setType(position);
            }
        });
        return mView;
    }

    private void initView() {
        mListView = mView.findViewById(R.id.list_menu);
        ArrayAdapter<String> adapter = new ArrayAdapter<>(
                getActivity(),R.layout.item,R.id.text,tips);
        mListView.setAdapter(adapter);
    }
}

fragment_menu: 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:orientation="horizontal"
    android:layout_height="match_parent">
    <ListView
        android:listSelector="#CFC3C3"
        android:background="#959090"
        android:divider="#CFC3C3"
        android:id="@+id/list_menu"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        />

</LinearLayout>

item:

<?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="wrap_content">
    <TextView
        android:gravity="center"
        android:id="@+id/text"
        android:paddingLeft="5dp"
        android:layout_width="match_parent"
        android:layout_height="30dp"
        android:layout_gravity="center"
        android:textSize="18sp"
        android:textColor="@color/black"
        android:text="折扣"/>

</LinearLayout>

悦读

道可道，非常道；名可名，非常名。 无名，天地之始，有名，万物之母。 故常无欲，以观其妙，常有欲，以观其徼。 此两者，同出而异名，同谓之玄，玄之又玄，众妙之门。

最新收录
回文串系列
3D基因组工具（HiC可视化）trackc--bioinfomatics tools 35
计算机毕业设计必看必学14297竞赛信息管理平台原创定制程序,java、PHP、python、小程序、文案全套、毕设成品等
ES6数组和对象常用方法
概率生成函数
Redis系列漏洞总结
MongoDB 数据放在不同的磁盘上
计算机毕业设计Java学生评奖管理系统(源码+系统+mysql数据库+lw文档）
Github 2024-11-16Rust开源项目日报 Top10
基于XDP技术的高性能rtp媒体转发服务程序
;