Android 高仿京东购物车

倒入依赖：

    略（。。。）

得到接口里面的数据信息。。。。。在bean包里面设置一种状态

//设置一种状态

      private boolean child_flag=false;

        public boolean isChild_flag() {
            return child_flag;
        }

        public void setChild_flag(boolean child_flag) {
            this.child_flag = child_flag;
        }

实现一个AddSubView类（自定义View）

主要功能：

public class AddSubView extends LinearLayout implements View.OnClickListener {

    private TextView sub;
    private TextView add;
    private EditText count;
    private AddClickListener addClickListener;
    private SubClickListener subClickListener;
    private static final String TAG = "AddSubView------------";
    public AddSubView(Context context) {
        this(context, null);
    }

    public AddSubView(Context context, @Nullable AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public AddSubView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        View view = View.inflate(context, R.layout.activity_add_sub_view, this);
        //获取控件
        sub = view.findViewById(R.id.sub);
        add = view.findViewById(R.id.add);
        count = view.findViewById(R.id.count);
        sub.setOnClickListener(this);
        add.setOnClickListener(this);
    }

    //点击事件
    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            //减少
            case R.id.sub:
                String c = count.getText().toString();
                int i = Integer.parseInt(c);
                if (i <= 0) {
                    return;
                }
                count.setText(--i + "");
                subClickListener.onSubClick(v,i);
                Log.d(TAG, "减-----" + i);

                break;
            //增加
            case R.id.add:
                String c1 = count.getText().toString();
                int i1 = Integer.parseInt(c1);

                count.setText(++i1 + "");
                addClickListener.onAddClick(v,i1);
                Log.d(TAG, "onClick() returned: " + "加===");
                break;
        }
    }

    public int getCount() {
        return Integer.parseInt(count.getText().toString().trim());
    }

    public void setCount(int s) {
        count.setText(s + "");
    }

    public interface AddClickListener {
        void onAddClick(View view, int count);
    }

    public interface SubClickListener {
        void onSubClick(View view, int count);
    }

    public void setOnAddClickListener(AddClickListener addClickListener) {
        this.addClickListener = addClickListener;
    }

    public void setOnSubClickListener(SubClickListener subClickListener) {
        this.subClickListener = subClickListener;
    }

}

自定义一个工具类 ——-》计算总价

public class SumUtils {
    public static String sum(List<CartBean.DataBean> list){
        double sum=0;

        for (int i=0;i<list.size ();i++){
            List<CartBean.ChildBean> list1 = list.get (i).getList ();

            for (int j=0;j<list1.size ();j++){
                CartBean.ChildBean childBean = list1.get (j);

                if(childBean.isChild_flag ()){
                    sum+=childBean.getPrice ()*childBean.getNum ();
                }
            }
        }

        return Double.toString (sum);
    }
}

主方法里面的方法：

public class ShoppingActivity extends AppCompatActivity implements ICartView,View.OnClickListener{
    private static final String TAG = "ShoppingActivity---";
    private ExpandableListView expandableListView;
    private CheckBox checkBox;
    private TextView sum;
    private Button js;
    private CheckBox cb;
    private  List<CartBean.DataBean> list;
    private MyExpandAdapter myExpandAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate (savedInstanceState);
        setContentView (R.layout.activity_shopping);

        initDatas();

        initViews();

    }

    private void initViews() {
        PresenterImpel presenterImpel = new PresenterImpel ();

        presenterImpel.ShowCartToView (new ModelImpel (presenterImpel),this);
    }

    private void initDatas() {
        //得到控件
        expandableListView = findViewById(R.id.expandlist);
        checkBox = findViewById(R.id.cb);
        sum = findViewById(R.id.sum);
        js = findViewById(R.id.js);
        cb = findViewById (R.id.cb);
        cb.setOnClickListener (this);
        checkBox.setOnClickListener(this);
        js.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()){
            case R.id.cb:
                boolean checked = cb.isChecked ();

                for (int i = 0; i<list.size (); i++){
                    CartBean.DataBean dataBean = list.get (i);

                    dataBean.setParent_flag (checked);

                    List<CartBean.ChildBean> list1 = dataBean.getList ();

                    for (int j=0;j<list1.size ();j++){
                        list1.get (j).setChild_flag (checked);
                    }
                }

                myExpandAdapter.notifyDataSetChanged ();

                //计算。。。。
                String count = SumUtils.sum (list);

                sum.setText (count);
                break;
            case R.id.js:
                Toast.makeText (ShoppingActivity.this,"结算了-----",Toast.LENGTH_SHORT).show ();
                break;
        }
    }

    @Override
    public void ShowCartToViews(List<CartBean.DataBean> list) {
        Log.d (TAG, "ShowCartToViews: "+list.size ());

        this.list = list;

        myExpandAdapter = new MyExpandAdapter (ShoppingActivity.this,list,this);

        expandableListView.setAdapter (myExpandAdapter);

        int childCount = expandableListView.getCount ();

        for (int i=0;i<childCount;i++){
            expandableListView.expandGroup (i);
        }
    }

    @Override
    public void getCount(String count) {
        Log.d (TAG, "总价: "+count);

        sum.setText ("总价："+count);
    }
}

设置适配器

public class MyExpandAdapter extends BaseExpandableListAdapter {
    private static final String TAG = "MyExpandAdapter---";
    private final Context context;
    private final List<CartBean.DataBean> list;
    private final ICartView iCartView;
    private ParentViewHolder parentViewHolder;
    private ChildViewHolder childViewHolder;

    public MyExpandAdapter(Context context, List<CartBean.DataBean> list, ICartView iCartView){
        this.context = context;

        this.list = list;

        this.iCartView = iCartView;
    }

    @Override
    public int getGroupCount() {
        return list.size ();
    }

    @Override
    public int getChildrenCount(int groupPosition) {
        return list.get(groupPosition).getList ().size ();
    }

    @Override
    public Object getGroup(int groupPosition) {
        return list.get (groupPosition);
    }

    @Override
    public Object getChild(int groupPosition, int childPosition) {
        return list.get (groupPosition).getList().get(childPosition);
    }

    @Override
    public long getGroupId(int groupPosition) {
        return groupPosition;
    }

    @Override
    public long getChildId(int groupPosition, int childPosition) {
        return childPosition;
    }

    @Override
    public boolean hasStableIds() {
        return true;
    }

    @Override
    public View getGroupView(final int groupPosition, boolean isExpanded, View convertView, final ViewGroup parent) {
        if(convertView==null){
            convertView = View.inflate (context, R.layout.parent_item,null);

            CheckBox parent_box = convertView.findViewById (R.id.parent_cb);
            TextView parent_title = convertView.findViewById (R.id.parent_title);

            parentViewHolder = new ParentViewHolder (parent_box, parent_title);

            convertView.setTag (parentViewHolder);
        }else{
            parentViewHolder = (ParentViewHolder) convertView.getTag ();
        }

        parentViewHolder.parent_title.setText (list.get (groupPosition).getSellerName ());

        //-----------------------------------------得到复选框的状态
        parentViewHolder.getParent_cb ().setChecked (list.get (groupPosition).isParent_flag ());

        parentViewHolder.getParent_cb ().setOnClickListener (new View.OnClickListener () {
            @Override
            public void onClick(View v) {
                boolean isChecked = list.get (groupPosition).isParent_flag ();

                isChecked=!isChecked;

                list.get (groupPosition).setParent_flag (isChecked);

                List<CartBean.ChildBean> list_parent = MyExpandAdapter.this.list.get (groupPosition).getList ();

                for (int i=0;i<list_parent.size ();i++){
                    list_parent.get (i).setChild_flag (isChecked);
                }
                notifyDataSetChanged ();

                //计算。。。。
                String sum = SumUtils.sum (list);

                iCartView.getCount (sum);
            }
            //-----------------------------------------得到复选框的状态
        });

        return convertView;
    }

    @Override
    public View getChildView(final int groupPosition, final int childPosition, boolean isLastChild, View convertView, ViewGroup parent) {
        if(convertView==null){
            convertView = View.inflate (context,R.layout.child_item,null);

            CheckBox child_cb = convertView.findViewById (R.id.child_cb);
            SimpleDraweeView child_pic = convertView.findViewById (R.id.child_pic);
            TextView child_title = convertView.findViewById (R.id.chid_title);
            TextView chile_price = convertView.findViewById (R.id.chid_price);
            AddSubView addSubView = convertView.findViewById (R.id.add_sub_view);
            Button delete = convertView.findViewById (R.id.delete);

            childViewHolder = new ChildViewHolder (child_cb, child_pic, child_title, chile_price,addSubView,delete);

            convertView.setTag (childViewHolder);


        }else{
            childViewHolder = (ChildViewHolder) convertView.getTag ();
        }

        final List<CartBean.ChildBean> child_list = this.list.get (groupPosition).getList ();

        String images = child_list.get (childPosition).getImages ();
        String pic_url = images.split ("\\|")[0];
        childViewHolder.child_pic.setImageURI (pic_url);
        childViewHolder.child_title.setText (child_list.get (childPosition).getTitle ());
        childViewHolder.child_price.setText (child_list.get (childPosition).getPrice ()+"");
        childViewHolder.addSubView.setCount (child_list.get (childPosition).getNum ());

        //设置点击事件，两个事件都要设置
        //添加的监听
        childViewHolder.getAddSubView().setOnAddClickListener(new AddSubView.AddClickListener() {
            @Override
            public void onAddClick(View view, int count) {
                list.get(groupPosition).getList().get(childPosition).setNum(count);
                //开始计算，如果选中了，就计算，没选中，就不计算
                boolean selected = list.get(groupPosition).getList().get(childPosition).isChild_flag ();
                Log.d(TAG, "onAddClick() returned: " + "计算开始");
                if (selected){
                    String sum = SumUtils.sum(list);
                    Log.d(TAG, "onAddClick() returned: " + sum);
                    iCartView.getCount (sum);
                }
            }
        });
        //减法
        childViewHolder.getAddSubView().setOnSubClickListener(new AddSubView.SubClickListener() {
            @Override
            public void onSubClick(View view, int count) {
                list.get(groupPosition).getList().get(childPosition).setNum(count);
                boolean selected = list.get(groupPosition).getList().get(childPosition).isChild_flag ();
                Log.d(TAG, "onAddClick() returned: " + "计算开始");
                if (selected){
                    String sum = SumUtils.sum(list);
                    Log.d(TAG, "onAddClick() returned: " + sum);
                    iCartView.getCount (sum);
                }
            }
        });


        //-----------------------------------------得到复选框的状态
        childViewHolder.getChild_cb ().setChecked (child_list.get (childPosition).isChild_flag ());

        //计算。。。。
        String sum = SumUtils.sum (list);

        iCartView.getCount (sum);

        childViewHolder.getDelete ().setOnClickListener (new View.OnClickListener () {
            @Override
            public void onClick(View v) {
                child_list.remove (childPosition);

                list.remove (groupPosition);

                notifyDataSetChanged ();
            }
        });

        return convertView;
    }



    @Override
    public boolean isChildSelectable(int groupPosition, int childPosition) {
        return false;
    }

    public class ParentViewHolder{
        private CheckBox parent_cb;
        private TextView parent_title;

        public ParentViewHolder(CheckBox parent_cb, TextView parent_title) {
            this.parent_cb = parent_cb;
            this.parent_title = parent_title;
        }

        public CheckBox getParent_cb() {
            return parent_cb;
        }

        public void setParent_cb(CheckBox parent_cb) {
            this.parent_cb = parent_cb;
        }

        public TextView getParent_title() {
            return parent_title;
        }

        public void setParent_title(TextView parent_title) {
            this.parent_title = parent_title;
        }
    }

    public class ChildViewHolder{
        private CheckBox child_cb;
        private SimpleDraweeView child_pic;
        private TextView child_title;
        private TextView child_price;
        private AddSubView addSubView;
        private Button delete;

        public ChildViewHolder(CheckBox child_cb, SimpleDraweeView child_pic, TextView child_title, TextView child_price, AddSubView addSubView, Button delete) {
            this.child_cb = child_cb;
            this.child_pic = child_pic;
            this.child_title = child_title;
            this.child_price = child_price;
            this.addSubView = addSubView;
            this.delete = delete;
        }

        public CheckBox getChild_cb() {
            return child_cb;
        }

        public void setChild_cb(CheckBox child_cb) {
            this.child_cb = child_cb;
        }

        public SimpleDraweeView getChild_pic() {
            return child_pic;
        }

        public void setChild_pic(SimpleDraweeView child_pic) {
            this.child_pic = child_pic;
        }

        public TextView getChild_title() {
            return child_title;
        }

        public void setChild_title(TextView child_title) {
            this.child_title = child_title;
        }

        public TextView getChild_price() {
            return child_price;
        }

        public void setChild_price(TextView child_price) {
            this.child_price = child_price;
        }

        public AddSubView getAddSubView() {
            return addSubView;
        }

        public void setAddSubView(AddSubView addSubView) {
            this.addSubView = addSubView;
        }

        public Button getDelete() {
            return delete;
        }

        public void setDelete(Button delete) {
            this.delete = delete;
        }
    }
}

布局文件：

activity_main:

<?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:background="#fff"
    android:orientation="vertical">

    <ExpandableListView
        android:id="@+id/expandable_list_view"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:groupIndicator="@null"
        android:layout_weight="1"></ExpandableListView>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <CheckBox
            android:id="@+id/cb"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" />

        <TextView
            android:id="@+id/sum"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="合计:0" />

        <Button
            android:id="@+id/js"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:background="#F00"
            android:text="去结算（0）" />
    </LinearLayout>
</LinearLayout>

item_child:

<?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"
    android:gravity="center_vertical"
    android:orientation="horizontal">

    <CheckBox
        android:id="@+id/child_cb"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <ImageView
        android:id="@+id/child_pic"
        android:layout_width="50dp"
        android:layout_height="50dp"
        android:src="@mipmap/ic_launcher" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TextView
            android:singleLine="true"
            android:id="@+id/child_title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="商品名"
            android:textSize="15sp" />

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal">


        <TextView
            android:singleLine="true"
            android:id="@+id/child_price"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="商品价格"
            android:textColor="#F00" />


         <com.bawie.chenzhiqiang.shopcar_demo.view.AddSubView
             android:id="@+id/add_sub_view"
             android:layout_width="100dp"
             android:layout_marginLeft="60dp"
             android:layout_height="wrap_content">
         </com.bawie.chenzhiqiang.shopcar_demo.view.AddSubView>
        </LinearLayout>
    </LinearLayout>

</LinearLayout>

item_parent:

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

    <CheckBox
        android:id="@+id/parent_cb"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <TextView
        android:id="@+id/parent_title"
        android:text="商家"
        android:singleLine="true"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

</LinearLayout>

activity_add_sub_vew:

<?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="horizontal">
    <TextView
        android:id="@+id/sub"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:background="@drawable/add_sub_shape"
        android:gravity="center"
        android:text="-"
        android:textSize="25sp" />

    <EditText
        android:id="@+id/count"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:background="@drawable/add_sub_shape"
        android:focusable="false"
        android:gravity="center"
        android:text="0" />

    <TextView
        android:id="@+id/add"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:background="@drawable/add_sub_shape"
        android:gravity="center"
        android:text="+"
        android:textSize="25sp" />
</LinearLayout>

在drawable文件夹下面创建效果：

add_sub_shap:

<?xml version="1.0" encoding="utf-8"?>
<shape
    android:shape="rectangle"
    xmlns:android="http://schemas.android.com/apk/res/android">
     <size android:width="100dp" android:height="30dp"/>
    <stroke android:width="1dp" android:color="#999999"/>
</shape>

添加删除操作：例如

//删除

       childViewHolder.getDelte().setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                child_list.remove(childPosition);
                notifyDataSetChanged();
            }
        });