Dizzy Coding

Tukang ngomong.

PRO :
#Ask #Android Studio #RecyclerView
Permisi, saya ingin bertanya tentang RecyclerView, saya sedang mencoba untuk membuat event clik untuk setiap data yang akan di tampilkan oleh RecyclerView.
Saya sudah mencoba tutorial dari  tutorial ini, dan ini Namun masih tidak bisa. malah muncul NullPointerExeption.
Dan berikut ini Error yang dimunculkan.
Mohon bantuannya ya.

Ok, langsung aja yuk

    Map<String, String> getData(){
        Map<String,String> operator = new HashMap<>();
        operator.put("62811","Telkomsel");
        operator.put("62812","Telkomsel");
        operator.put("62813","Telkomsel");
        operator.put("62821","Telkomsel");
        operator.put("62822","Telkomsel");
        operator.put("62823","Telkomsel");
        operator.put("62851","Telkomsel");
        operator.put("62852","Telkomsel");
        operator.put("62853","Telkomsel");
        operator.put("62814","Indosat");
        operator.put("62815","Indosat");
        operator.put("62816","Indosat");
        operator.put("62855","Indosat");
        operator.put("62856","Indosat");
        operator.put("62857","Indosat");
        operator.put("62858","Indosat");
        operator.put("62817","XL / Axis");
        operator.put("62818","XL / Axis");
        operator.put("62819","XL / Axis");
        operator.put("62859","XL / Axis");
        operator.put("62877","XL / Axis");
        operator.put("62878","XL / Axis");
        operator.put("62879","XL / Axis");
        operator.put("62831","XL / Axis");
        operator.put("62833","XL / Axis");
        operator.put("62835","XL / Axis");
        operator.put("62836","XL / Axis");
        operator.put("62837","XL / Axis");
        operator.put("62838","XL / Axis");
        operator.put("62839","XL / Axis");
        operator.put("6288","Smartfren");
        operator.put("62899","Three");
        operator.put("62898","Three");
        operator.put("62897","Three");
        operator.put("62896","Three");
        operator.put("62895","Three");
        operator.put("62894","Three");
        operator.put("62893","Three");
        return operator;
    }

    String cekOp(String pref){
        String ret ="";
        Map<String, String> operator = getData();
        for (Map.Entry<String,String> entry : operator.entrySet()){
            if (pref.equalsIgnoreCase(entry.getKey())){
                ret = entry.getValue();
            }
        }
        if (ret.equalsIgnoreCase("")){
            ret = "Tidak ditemukan";
        }
        return ret;
    }

<?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">

    <LinearLayout
        android:id="@+id/up"
        android:layout_width="match_parent"
        android:layout_height="match_parent">


        <EditText
            android:id="@+id/phone"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:ems="10"
            android:inputType="phone" />
        <Button
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Cek" />
    </LinearLayout>
    <LinearLayout
        android:layout_centerVertical="true"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView
            android:id="@+id/operator"
            android:text="Test"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </LinearLayout>

</RelativeLayout>

        final EditText no = findViewById(R.id.phone);
        Button button = findViewById(R.id.button);
        final TextView hasil = findViewById(R.id.operator);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String noHp = no.getText().toString();
                if (noHp.length() > 4){
                    noHp = noHp.substring(0,5);
                }
                hasil.setText(cekOp(noHp));
            }
        });

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String noHp = no.getText().toString();
                if (noHp.length() > 4){
                    // jika panjang karakter lebih dari 4
                    if (noHp.substring(0,1).equalsIgnoreCase("0")){
                        // jika karakter pertamanya adalah 0
                        // maka replace angka 0 tersebut dengan 62
                        noHp = noHp.replace("0","62");
                    }
                    noHp = noHp.substring(0,5);
                }
                hasil.setText(cekOp(noHp));
            }
        });

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String noHp = no.getText().toString();
                if (noHp.length() > 4){
                    // jika panjang karakter lebih dari 4
                    if (noHp.substring(0,1).equalsIgnoreCase("0")){
                        // jika karakter pertamanya adalah 0
                        // maka replace angka 0 tersebut dengan 62
                        noHp = noHp.replace("0","62");
                    }
                    if (noHp.contains("6288")){
                        noHp = noHp.substring(0,4);
                    }
                    else{
                        noHp = noHp.substring(0,5);
                    }
                }
                hasil.setText(cekOp(noHp));
            }
        });