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トップに関する質問Android（Java）で別のActivityにあるListViewのint positionの値をMainActivityに取得する方法を教えて下さい!

編集履歴

質問編集履歴

2

画像を追加しました

2021/02/01 01:46

投稿

退会済みユーザー
test CHANGED
File without changes
test CHANGED
@@ -267,3 +267,7 @@
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  }
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  ```
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+
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+ ListViewのレイアウト
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+
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+ ![イメージ説明](2db6ea4453fe77205a7c0ca1bf976430.png)

1

コードを詳細に載せました

2021/02/01 01:46

投稿

退会済みユーザー
test CHANGED
File without changes
test CHANGED
@@ -6,116 +6,264 @@
6
6
 
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7
  ■MainActivity
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8
 
9
- refMsg.addChildEventListener(new ChildEventListener() {
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-
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- @Override
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-
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- public void onChildAdded(DataSnapshot dataSnapshot, String s) {
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-
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- //データー取得
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-
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- Post value = dataSnapshot.getValue(Post.class);
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-
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-
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-
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- //リストに追加
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-
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- items.add(value);
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-
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-
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-
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- //画面を更新
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-
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- postAdapter.clear();
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-
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- postAdapter.addAll(items);
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-
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- postAdapter.notifyDataSetChanged();
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-
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- }
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-
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-
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-
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- public void good(View v) {
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-
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- //ListViewのボタンの処理を行いたいところ
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-
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- }
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-
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-
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+ public class MainActivity extends AppCompatActivity implements View.OnClickListener {
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+
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+
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+
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+ //gor firebase
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+
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+ FirebaseDatabase database = FirebaseDatabase.getInstance();
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+
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+ DatabaseReference refMsg = database.getReference("message");
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+
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+
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+
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+ //view component
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+
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+ ListView mListView;
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+
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+ Button mButton;
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+
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+ TextView likepoint;
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+
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+
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+
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+ //fields
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+
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+ ArrayList<Post> items;
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+
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+
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+
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+ // adapter
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+
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+ PostAdapter postAdapter;
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+
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+
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+
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+
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+
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+ ArrayList arrayList;
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+
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+
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+
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+ @Override
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+
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+ protected void onCreate(Bundle savedInstanceState) {
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+
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+ super.onCreate(savedInstanceState);
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+
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+ setContentView(R.layout.activity_main);
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+
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+
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+
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+ //関連付け
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+
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+ mListView = (ListView) findViewById(R.id.list_view);
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+
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+ mButton = (Button) findViewById(R.id.button);
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+
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+ // likepoint = (TextView) findViewById(R.id.likepoint);
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+
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+ mButton.setOnClickListener(this);
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+
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+
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+
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+ items = new ArrayList<>();
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+
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+ postAdapter = new PostAdapter(this, 0, items);
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+
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+ mListView.setAdapter(postAdapter);
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+
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+ refMsg.addChildEventListener(new ChildEventListener() {
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+
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+ @Override
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+
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+ public void onChildAdded(DataSnapshot dataSnapshot, String s) {
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+
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+ //データー取得
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+
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+ Post value = dataSnapshot.getValue(Post.class);
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+
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+
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+
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+ //リストに追加
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+
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+ items.add(value);
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+
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+
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+
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+ //画面を更新
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+
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+ postAdapter.clear();
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+
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+ postAdapter.addAll(items);
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+
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+ postAdapter.notifyDataSetChanged();
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+
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+
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+
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+ }
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+
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+
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+
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+ @Override
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+
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+ public void onChildChanged(DataSnapshot dataSnapshot, String s) {
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+
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+
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+
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+ }
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+
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+
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+
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+ @Override
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+
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+ public void onChildRemoved(DataSnapshot dataSnapshot) {
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+
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+
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+
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+ }
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+
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+
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+
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+ @Override
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+
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+ public void onChildMoved(DataSnapshot dataSnapshot, String s) {
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+
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+
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+
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+ }
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+
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+
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+
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+ @Override
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+
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+ public void onCancelled(DatabaseError databaseError) {
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+
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+
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+
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+ }
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+
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+ });
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+
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+ }
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+
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+ public void good(View v) {
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+
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+ //ListView上のボタンの処理を行いたいところ
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+
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+ }
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  ■PostAdapter.java
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- public PostAdapter(Context context, int resource, List<Post> objects) {
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-
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- -省略-
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-
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-
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-
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- }
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-
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- ~省略~
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-
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- }
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-
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-
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-
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-
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-
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- @Override
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-
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- public View getView(int position, View convertView, ViewGroup parent) {
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-
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-
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-
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- //もともとのコード
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-
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- // Post item = getItem(position);
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-
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-
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-
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- //順序を逆にする
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-
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- Post item = getItem(getCount() - 1 - position);
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-
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-
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-
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- final ViewHolder viewHolder;
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-
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-
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-
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- if (convertView != null) {
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-
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- viewHolder = (ViewHolder) convertView.getTag();
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-
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- } else {
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-
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- convertView = LayoutInflater.from(getContext()).inflate(R.layout.listview_item_post, parent, false);
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-
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- viewHolder = new ViewHolder();
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-
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- viewHolder.userNameText = (TextView) convertView.findViewById(R.id.username);
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-
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- ~省略~
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-
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- }
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-
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- viewHolder.userNameText.setText(item.getUserName());
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-
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- viewHolder.messageText.setText(item.getMessage());
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-
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-
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-
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- ~省略~
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-
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-
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-
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- return convertView;
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-
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-
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-
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- }
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+ public class PostAdapter extends ArrayAdapter<Post> {
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+
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+
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+
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+ List<Post> items;
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+
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+
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+
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+
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+
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+ public PostAdapter(Context context, int resource, List<Post> objects) {
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+
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+ super(context, resource);
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+
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+ items = objects;
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+
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+
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+
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+ }
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+
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+ static class ViewHolder {
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+
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+ TextView userNameText;
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+
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+ TextView messageText;
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+
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+ TextView likepoint;
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+
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+ }
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+
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+
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+
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+
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+
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+ @Override
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+
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+ public View getView(int position, View convertView, ViewGroup parent) {
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+
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+
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+
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+ //順序を逆にする
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+
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+ Post item = getItem(getCount() - 1 - position);
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+
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+
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+
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+ final ViewHolder viewHolder;
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+
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+
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+
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+ if (convertView != null) {
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+
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+ viewHolder = (ViewHolder) convertView.getTag();
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+
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+ } else {
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+
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+ convertView = LayoutInflater.from(getContext()).inflate(R.layout.listview_item_post, parent, false);
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+
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+ viewHolder = new ViewHolder();
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+
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+ viewHolder.userNameText = (TextView) convertView.findViewById(R.id.username);
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+
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+ viewHolder.messageText = (TextView) convertView.findViewById(R.id.message);
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+
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+ viewHolder.likepoint = (TextView) convertView.findViewById(R.id.likepoint);
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+
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+ convertView.setTag(viewHolder);
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+
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+ }
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+
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+ viewHolder.userNameText.setText(item.getUserName());
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+
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+ viewHolder.messageText.setText(item.getMessage());
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+
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+
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+
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+ int likespointnumber = item.getLike();
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+
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+ String likepointtext = String.valueOf(likespointnumber);
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+
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+ viewHolder.likepoint.setText(likepointtext);
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+
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+
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+
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+ return convertView;
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+
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+
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+
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+ }
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+
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+
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+
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+ @Override
254
+
255
+ public int getCount() {
256
+
257
+ return items.size();
258
+
259
+ }
260
+
261
+ @Override
262
+
263
+ public Post getItem(int position) {
264
+
265
+ return items.get(position);
266
+
267
+ }
120
268
 
121
269
  ```