如何创建自定义适配器以将 cardview 用于片段内的列表视图

Question

i want to use card view inside my list view which is inside a fragment to show 2 variable, i already can connect to database and show only one variable "nama_matkul" from json into my list view, but i need to show "nama_matkul" and "sks" so i am creating a cardview but i am confused to make costum adapter for it

this is my json response

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

this is my method inside fragment to initialize list view

 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);

                }
            }

this is my cardview (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>

i found this answer from another post but still confuse to change into my needs ,post can be found at custom adapter for listview in fragment Android

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-jr 请在此链接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

Use your Custom Adapter Class File Before SetAdapter.

CustomAdapter adapter = new 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);

            }
        }