Question

我想在列表视图中使用卡片视图，该视图在一个片段中以显示2个变量，我已经可以连接到数据库，并且仅将json中的一个变量“ nama_matkul”显示到我的列表视图中，但是我需要显示“ nama_matkul”和“ sks”，因此我正在创建cardview，但我很困惑为此制作Costum适配器

这是我的json响应

{
"error": false,
"matkul_mhs": [{
"nama_matkul": "matkul_3",
"sks": 3
}]}

这是我在片段内初始化列表视图的方法

 public void initListView1(){
        Call<MatkulMhs> getMatkulMhs = mApiService.getMatkulMhs(
                mPrefs.getUserID());
        getMatkulMhs.enqueue(new Callback<MatkulMhs>() {
            @Override
            public void onResponse(Call<MatkulMhs> call, Response<MatkulMhs> response) {
                boolean iserror_ = response.body().getError();
                if (iserror_ == false) {
                    List<Matkul_Mhs> list = new ArrayList<>();
                    list = response.body().getMatkulMhs();
                    nama_matkul = new String[list.size()];
                    for (int i =0;i<list.size();i++) {
                        nama_matkul[i] = list.get(i).getNamaMatkul();
                    }
                    ArrayAdapter<String> adapter = new ArrayAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, nama_matkul);
                    listview1.setAdapter(adapter);

                }
            }

这是我的名片视图（form_mhs_02_cardview.xml）

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

    <androidx.cardview.widget.CardView
        android:id="@+id/card_view"
        android:layout_width="fill_parent"
        android:layout_height="100dp"
        android:layout_margin="5dp"
        card_view:cardCornerRadius="2dp"
        card_view:contentPadding="10dp">

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:orientation="vertical"
            android:background="@drawable/rounded_sqrwht"
            android:padding="10dp"
            >

            <TextView
                android:id="@+id/tv_matkul"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Mata Kuliah 1 "
                android:textSize="25dp"
                android:textColor="@color/colorPrimaryDark"
                android:textStyle=""
                android:singleLine="true"
                />
            <TextView
                android:id="@+id/tv_sks"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="3 sks"
                android:textSize="20dp"
                android:textColor="@color/black"
                android:singleLine="true"
                />
        </LinearLayout>

    </androidx.cardview.widget.CardView>

</LinearLayout>

我从另一篇文章中找到了这个答案，但仍然对改变自己的需求感到困惑，帖子可以在custom adapter for listview in fragment Android

中找到

public class CustomAdapter extends ArrayAdapter<HashMap<String,String>>
{
    private ArrayList<HashMap<String,String>> callLogData;
    private Context context;
    private int resource;
    private View view;
    private Holder holder;
    private HashMap<String,String> hashMap;
    public CustomAdapter(Context context, int resource,ArrayList<HashMap<String, String>> objects)
    {
        super(context, resource, objects);
        this.context=context;
        this.resource=resource;
        this.callLogData=objects;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {

        LayoutInflater inflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view=inflater.inflate(resource, parent,false);

        holder=new Holder();
        holder.text_matkul=(TextView)view.findViewById(R.id.tv_matkul);
        holder.text_sks=(TextView)view.findViewById(R.id.tv_sks);

        hashMap=callLogData.get(position);

        Date date=new Date(Long.parseLong(hashMap.get(CallLog.Calls.DATE)));
        java.text.DateFormat dateFormat=DateFormat.getDateFormat(context);
        java.text.DateFormat timeformat=DateFormat.getTimeFormat(context);


        holder.text_matkul.setText(hashMap.get(CallLog.Calls.NUMBER));
        holder.text_sks.setText(timeformat.format(date));

        return view;
    }

    public class Holder
    {
        TextView text_matkul;
        TextView text_sks;
    }

}

Answer 1

@ togan-j-r，请在链接https://medium.com/@Pang_Yao/android-fragment-use-recyclerview-cardview-4bc10beac446上查看此示例，并尝试按照演示示例进行实施。

Answer 2

public class CustomAdapter extends ArrayAdapter<HashMap<String, String>> {
    private final ArrayList<HashMap<String, String>> callLogData;
    private final Context context;
    private final int resource;

    /*
    This TODO code won't cause any issue even if not done.
    */
    //TODO : Check below comment
    private View view;

    //TODO :: NEED TO REMOVE as adapter handle multiple items therefore no meaning in having single field of holder object
    private Holder holder;
    //TODO :: NEED TO REMOVE same as above. you should get item from based on position provided in getView method no need to keep reference to it
    private HashMap<String, String> hashMap;

    public CustomAdapter(Context context, int resource, ArrayList<HashMap<String, String>> objects) {
        super(context, resource, objects);
        this.context = context;
        this.resource = resource;
        callLogData = objects;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        //Added local instance of holder
        View view = inflater.inflate(resource, parent, false);
        //Added local instance of holder
        Holder holder = new Holder();
        holder.text_matkul = (TextView) view.findViewById(R.id.tv_matkul);
        holder.text_sks = (TextView) view.findViewById(R.id.tv_sks);
        //Added local instance of holder
        HashMap<String, String> hashMap = callLogData.get(position);

        //Commenting below code
        /*
                Date date=new Date(Long.parseLong(hashMap.get(CallLog.Calls.DATE)));
                java.text.DateFormat dateFormat=DateFormat.getDateFormat(context);
                java.text.DateFormat timeformat=DateFormat.getTimeFormat(context);
        */


        holder.text_matkul.setText(hashMap.get("nama_matkul"));
        holder.text_sks.setText("sks");

        return view;
    }

    public class Holder {
        TextView text_matkul;
        TextView text_sks;
    }

}


public void initListView1() {
    Call<MatkulMhs> getMatkulMhs = mApiService.getMatkulMhs(
            mPrefs.getUserID());
    getMatkulMhs.enqueue(new Callback<MatkulMhs>() {
        @Override
        public void onResponse(Call<MatkulMhs> call, Response<MatkulMhs> response) {
            boolean iserror_ = response.body().getError();
            if (iserror_ == false) {
                List<Matkul_Mhs> list = new ArrayList<>();
                list = response.body().getMatkulMhs();
                ArrayList<HashMap<String, String>> nama_matkul = new ArrayList<>();
                for (int i = 0; i < list.size(); i++) {
                    HashMap<String, String> item = new HashMap<String, String>();
                    item.put("nama_matkul", list.get(i).getNamaMatkul());
                    item.put("sks", list.get(i).getSKS());
                    nama_matkul.add(item);
                }
                //Note: layout resource changed to your card view and ArrayAdapter  to CustomAdapter
                CustomAdapter adapter = new CustomAdapter(getActivity(), R.layout.form_mhs_02_cardview, nama_matkul);
                listview1.setAdapter(adapter);

            }
        }
    }
}

Answer 3

在SetAdapter之前使用自定义适配器类文件。

CustomAdapter适配器=新的CustomAdapter（getActivity（），android.R.layout.simple_list_item_1，nama_matkul）;

 public void initListView1(){
    Call<MatkulMhs> getMatkulMhs = mApiService.getMatkulMhs(
            mPrefs.getUserID());
    getMatkulMhs.enqueue(new Callback<MatkulMhs>() {
        @Override
        public void onResponse(Call<MatkulMhs> call, Response<MatkulMhs> response) {
            boolean iserror_ = response.body().getError();
            if (iserror_ == false) {
                List<Matkul_Mhs> list = new ArrayList<>();
                list = response.body().getMatkulMhs();
                nama_matkul = new String[list.size()];
                for (int i =0;i<list.size();i++) {
                    nama_matkul[i] = list.get(i).getNamaMatkul();
                }
                CustomAdapter <String> adapter = new CustomAdapter<String>(getActivity(), android.R.layout.simple_list_item_1, nama_matkul);
                listview1.setAdapter(adapter);

            }
        }

如何创建自定义适配器以将cardview用于片段内的列表视图

3 个答案: