ボタンが押下されたら、TextViewに配列が順番に表示される。

Java初心者です。
タイトルと重複しますが、ボタンが押下されると配列の文字列が順番に1つずつ表示させるにはどうすればよいですか？テキスト表示に、時間差で自由に設定できるスリープ機能も追加したいです。

Java
1   public void SetButtonOnClick(View v) {
2        TextView message;
3        message = (TextView) this.findViewById(R.id.Text1);
4
5        String[] word = { "Pretty, Cool, Weird" };
6        StringBuilder builder = new StringBuilder();
7
8        String[] fruits = word.split(",");
9        for (String s: fruits)
10        {
11            builder.append(s);
12            builder.append(" ");
13            message.setText(builder.toString().trim());
14        }

行動規範の内容に同意します

回答1件

MainActivity.java

java
1import androidx.appcompat.app.AppCompatActivity;
2
3import android.os.*;
4import android.text.*;
5import android.widget.*;
6
7class ContinuousSetter implements Runnable {
8  interface Callback {
9    void begin(ContinuousSetter setter);
10    void end(ContinuousSetter setter);
11  }
12
13  private Handler handler;
14  private TextView view;
15  private int length = -1;
16  private long delay = 200; //[ms]
17  private Object[] lock = new Object[0];
18
19  private String text;
20  private Callback callback;
21
22  ContinuousSetter(Handler handler, TextView view) {
23    this.handler = handler;
24    this.view = view;
25  }
26
27  boolean isRunning() {
28    return (length >= 0);
29  }
30
31  void start(String text, Callback callback) {
32    if(text == null) throw new NullPointerException();
33    synchronized(lock) {
34      if(length >= 0) return;
35      length = 0;
36    }
37    this.text = text;
38    this.callback = callback;
39
40    view.setText("");
41    if(this.callback != null) callback.begin(this);
42    handler.postDelayed(this, delay);
43  }
44
45  @Override
46  public void run() {
47    synchronized(lock) {
48      if(++length <= text.length()) {
49        view.setText(text.substring(0, length));
50        if(length < text.length()) {
51          handler.postDelayed(this, delay);
52          return;
53        }
54      }
55      length = -1;
56      if(this.callback != null) callback.end(this);
57      callback = null;
58      text = null;
59    }
60  }
61}
62
63public class MainActivity extends AppCompatActivity {
64
65  @Override
66  protected void onCreate(Bundle savedInstanceState)  {
67    super.onCreate(savedInstanceState);
68    setContentView(R.layout.activity_main);
69
70    EditText editText = findViewById(R.id.editText);
71
72    TextView textView = findViewById(R.id.textView);
73    ContinuousSetter setter = new ContinuousSetter(new Handler(getMainLooper()), textView);
74
75    Button startButton = findViewById(R.id.startButton);
76    startButton.setOnClickListener(v -> {
77      setter.start(editText.getText().toString(),
78              new ContinuousSetter.Callback() {
79                @Override
80                public void begin(ContinuousSetter setter) {
81                  startButton.setEnabled(false);
82                }
83                @Override
84                public void end(ContinuousSetter setter) {
85                  startButton.setEnabled(true);
86                }
87              });
88    });
89
90    editText.addTextChangedListener(new TextWatcher() {
91      @Override
92      public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
93      @Override
94      public void onTextChanged(CharSequence s, int start, int before, int count) {}
95      @Override
96      public void afterTextChanged(Editable s) {
97        if(!setter.isRunning()) startButton.setEnabled(s.length() > 0);
98      }
99    });
100  }
101}

レイアウト: activity_main.xml

xml
1<?xml version="1.0" encoding="utf-8"?>
2<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
3    xmlns:app="http://schemas.android.com/apk/res-auto"
4    xmlns:tools="http://schemas.android.com/tools"
5    android:layout_width="match_parent"
6    android:layout_height="match_parent"
7    tools:context=".MainActivity">
8
9  <EditText
10      android:id="@+id/editText"
11      android:layout_width="0dp"
12      android:layout_height="wrap_content"
13      android:hint="message"
14      android:text="Pretty, Cool, Weird"
15      android:textSize="20dp"
16      app:layout_constraintBottom_toTopOf="@id/startButton"
17      app:layout_constraintLeft_toLeftOf="parent"
18      app:layout_constraintRight_toRightOf="parent"
19      app:layout_constraintTop_toTopOf="parent" />
20
21  <Button
22      android:id="@+id/startButton"
23      android:layout_width="wrap_content"
24      android:layout_height="wrap_content"
25      android:text="start"
26      app:layout_constraintBottom_toTopOf="@id/textView"
27      app:layout_constraintLeft_toLeftOf="parent"
28      app:layout_constraintRight_toRightOf="parent"
29      app:layout_constraintTop_toBottomOf="@id/editText" />
30
31  <TextView
32      android:id="@+id/textView"
33      android:layout_width="wrap_content"
34      android:layout_height="wrap_content"
35      android:text="Hello World!"
36      android:textSize="20dp"
37      app:layout_constraintBottom_toBottomOf="parent"
38      app:layout_constraintLeft_toLeftOf="parent"
39      app:layout_constraintRight_toRightOf="parent"
40      app:layout_constraintTop_toBottomOf="@id/startButton" />
41</androidx.constraintlayout.widget.ConstraintLayout>