[3] ListView

1. ListView

Layout

<?xml version="1.0" encoding="utf-8"?> <LinearLayout android:id="@+id/inflater_layer" xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <TextView android:id="@+id/inflater_txt" android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:text="inflater" android:textSize="20dp"/> </LinearLayout>

* ListView의 항목으로 들어갈 Layout(activity_inflater.xml) 생성 (기존 : activity_main.xml)

* id를 등록

Activity

public class MainActivity extends AppCompatActivity { ListView list_view; MyAdapter adapter; ArrayList<String> arr; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); arr = new ArrayList<>(); arr.add("test1"); arr.add("test2"); list_view = (ListView)findViewById(R.id.list_view); adapter = new MyAdapter(this, R.layout.activity_inflater, arr); list_view.setAdapter(adapter); } }

* 각 객체 생성 및 연결.

* ListView에 adapter 세팅.

* 예제의 경우 String List값으로 세팅.

MyAdapter

public class MyAdapter extends ArrayAdapter<String>{ Context context; int resource; ArrayList<String> arr; public MyAdapter(Context context, int resource, ArrayList<String> arr) { super(context, resource, arr); this.context = context; this.resource = resource; this.arr = arr; } @NonNull @Override public View getView(int position, View convertView, ViewGroup parent) { LayoutInflater linf = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); convertView = linf.inflate(resource, null); TextView textView = (TextView)convertView.findViewById(R.id.inflater_txt); textView.setText(arr.get(position)); return convertView; } }

* 상황에 맞는 adapter 상속받음.

* list의 개수에 따라 getView가 자동으로 호출.

* position : List의 위치

* convertView : ListView의 각 항목

2. 결과화면

3. ItemClickListener

MyAdapter

public class MyAdapter extends ArrayAdapter<String>{ Context context; int resource; ArrayList<String> arr; public MyAdapter(Context context, int resource, ArrayList<String> arr, ListView list_view) { super(context, resource, arr); this.context = context; this.resource = resource; this.arr = arr; list_view.setOnItemClickListener( click ); } AdapterView.OnItemClickListener click = new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) { Toast.makeText(getContext(), String.format("position : %d, Text : %s", i, arr.get(i)), Toast.LENGTH_SHORT).show(); } }; @NonNull @Override public View getView(int position, View convertView, ViewGroup parent) { LayoutInflater linf = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE); convertView = linf.inflate(resource, null); TextView textView = (TextView)convertView.findViewById(R.id.inflater_txt); textView.setText(arr.get(position)); return convertView; } }

* MyAdapter 생성자에서 ListView 객체를 인자로 전달받음.

* ListView 객체에 ItemClickListener 등록.

Activity

public class MainActivity extends AppCompatActivity { ListView list_view; MyAdapter adapter; ArrayList<String> arr; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); arr = new ArrayList<>(); arr.add("test1"); arr.add("test2"); list_view = (ListView)findViewById(R.id.list_view); adapter = new MyAdapter(this, R.layout.activity_inflater, arr, list_view); list_view.setAdapter(adapter); } }

* adapter 생성자에서 추가로 ListView 객체를 전달.

4. 결과화면