如何隨機化一個沒有任何重複/重複字符串的數組？

我可以將我設置爲android中每個按鈕的字符串隨機化，但有相同字母的重複。我怎麼做沒有任何重複的信件？如何隨機化一個沒有任何重複/重複字符串的數組？

Random random = new Random(); 
    String[] letters = {"G","O","K","U","H","A","N","L","Z","M"}; 

    c1r1 = (Button) findViewById(R.id.btn1); 
    c2r1 = (Button) findViewById(R.id.btn2); 
    c3r1 = (Button) findViewById(R.id.btn3); 
    c4r1 = (Button) findViewById(R.id.btn4); 
    c5r1 = (Button) findViewById(R.id.btn5); 
    c1r2 = (Button) findViewById(R.id.btn6); 
    c2r2 = (Button) findViewById(R.id.btn7); 
    c3r2 = (Button) findViewById(R.id.btn8); 
    c4r2 = (Button) findViewById(R.id.btn9); 
    c5r2 = (Button) findViewById(R.id.btn10); 
    first = (Button) findViewById(R.id.first); 
    second = (Button) findViewById(R.id.second); 
    third = (Button) findViewById(R.id.third); 
    fourth = (Button) findViewById(R.id.fourth); 

    c1r1.setText("" + letters[random.nextInt(letters.length)]); 
    c2r1.setText("" + letters[random.nextInt(letters.length)]); 
    c3r1.setText("" + letters[random.nextInt(letters.length)]); 
    c4r1.setText("" + letters[random.nextInt(letters.length)]); 
    c5r1.setText("" + letters[random.nextInt(letters.length)]); 
    c1r2.setText("" + letters[random.nextInt(letters.length)]); 
    c2r2.setText("" + letters[random.nextInt(letters.length)]); 
    c3r2.setText("" + letters[random.nextInt(letters.length)]); 
    c4r2.setText("" + letters[random.nextInt(letters.length)]); 
    c5r2.setText("" + letters[random.nextInt(letters.length)]);

來源

2017-04-17 Jose G.

public ArrayList<String> arrayList; 

@Override 
protected void onCreate (Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    arrayList=new ArrayList<String>(); 

    String[] letters = {"G","O","K","U","H","A","N","L","Z","M"}; 
    for (String s:letters) 
     arrayList.add(s); 



    c1r1.setText("" + getRandom()); 
    c2r1.setText("" + getRandom()); 
    ... 
    ... 

} 


public String getRandom(){ 

    String randomString=arrayList.get(random.nextInt(arrayList.size())); 
    arrayList.remove(randomString); 
    return randomString; 

}

來源

2017-04-17 15:22:26 Aryan

呃，等等。你使用我的解決方案並清理了它？ :) –

謝謝@EmanuelSeibold和Abhishek Aryan。它完美的工作:) –

private String[] letters = {"G","O","K","U","H","A","N","L","Z","M"}; 
private List<String> list = new ArrayList<String>(Arrays.asList(letters)); 

private String getUniqueRandomString() { 
     int i = ThreadLocalRandom.current().nextInt(0, letters.size() + 1); 
     String s = letters.get(i); 
     letters.remove(i); 
     return s; 
} 
private void init() { 

    c1r1 = (Button) findViewById(R.id.btn1); 
    c2r1 = (Button) findViewById(R.id.btn2); 
    c3r1 = (Button) findViewById(R.id.btn3); 
    c4r1 = (Button) findViewById(R.id.btn4); 
    c5r1 = (Button) findViewById(R.id.btn5); 
    c1r2 = (Button) findViewById(R.id.btn6); 
    c2r2 = (Button) findViewById(R.id.btn7); 
    c3r2 = (Button) findViewById(R.id.btn8); 
    c4r2 = (Button) findViewById(R.id.btn9); 
    c5r2 = (Button) findViewById(R.id.btn10); 
    first = (Button) findViewById(R.id.first); 
    second = (Button) findViewById(R.id.second); 
    third = (Button) findViewById(R.id.third); 
    fourth = (Button) findViewById(R.id.fourth); 

    c1r1.setText(getUniqueRandomString()); 
    c2r1.setText(getUniqueRandomString()); 

// ... 

}

來源

2017-04-17 15:13:53

你可以使用 Collections.shuffle（名單列表）

來源

2017-04-17 15:27:57 makrom

如何隨機化一個沒有任何重複/重複字符串的數組？

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