Question

我想制作七个数字幸运抽奖的应用程序。这是我的代码。但我不知道为什么当我多次单击这两个按钮时应用程序将停止。单击“清除”后，“下一个数字”按钮将无响应。有谁知道为什么？

MainActivity.java

public class MainActivity extends AppCompatActivity {
TextView[] arr = new TextView[7];
int[] num = new int[6];
int count = 0;
TextView number_7;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    arr[0] = ((TextView) findViewById(R.id.tv_number_one));
    arr[1] = ((TextView) findViewById(R.id.tv_number_two));
    arr[2] = (TextView)findViewById(R.id.tv_number_three);
    arr[3] = (TextView)findViewById(R.id.tv_number_four);
    arr[4] = (TextView)findViewById(R.id.tv_number_five);
    arr[5] = (TextView)findViewById(R.id.tv_number_six);
    number_7 = (TextView)findViewById(R.id.tv_number_seven);

}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}
public void generate(View v)
{
    Random myRandom = new Random();
    if (count >= 7) {
        clear(arr[0]);
        clear(arr[1]);
        clear(arr[2]);
        clear(arr[3]);
        clear(arr[4]);
        clear(arr[5]);
        clear(arr[6]);
        for (TextView tv : arr) tv.setText("?");
    }
    switch (count){
        case(0):{
            num[0]= myRandom.nextInt(48) + 1;
            arr[0].setText(String.valueOf(num[0]));
            break;
        }
        case(1):{
            num[1]= myRandom.nextInt(48) + 1;
            arr[1].setText(String.valueOf(num[1]));
            break;
        }
        case(2):{
            num[2]= myRandom.nextInt(48) + 1;
            arr[2].setText(String.valueOf(num[2]));
            break;
        }
        case(3):{
            num[3]= myRandom.nextInt(48) + 1;
            arr[3].setText(String.valueOf(num[3]));
            break;
        }
        case(4):{
            num[4]= myRandom.nextInt(48) + 1;
            arr[4].setText(String.valueOf(num[4]));
            break;
        }
        case(5):{
            num[5]= myRandom.nextInt(48) + 1;
            arr[5].setText(String.valueOf(num[5]));
            break;
        }
        case(6):{
            int num_7;
            Arrays.sort(num);
            num_7= myRandom.nextInt(48) + 1;
            arr[0].setText(String.valueOf(num[0]));
            arr[1].setText(String.valueOf(num[1]));
            arr[2].setText(String.valueOf(num[2]));
            arr[3].setText(String.valueOf(num[3]));
            arr[4].setText(String.valueOf(num[4]));
            arr[5].setText(String.valueOf(num[5]));
            number_7.setText(String.valueOf(num_7));
            break;
        }

    }
    count++;


}
public void clear(View v){
    TextView num_1 = (TextView)findViewById(R.id.tv_number_one);
    num_1.setText("?");
    TextView num_2 = (TextView)findViewById(R.id.tv_number_two);
    num_2.setText("?");
    TextView num_3 = (TextView)findViewById(R.id.tv_number_three);
    num_3.setText("?");
    TextView num_4 = (TextView)findViewById(R.id.tv_number_four);
    num_4.setText("?");
    TextView num_5 = (TextView)findViewById(R.id.tv_number_five);
    num_5.setText("?");
    TextView num_6 = (TextView)findViewById(R.id.tv_number_six);
    num_6.setText("?");
    TextView num_7 = (TextView)findViewById(R.id.tv_number_seven);
    num_7.setText("?");
}
}

activity_main

 <TextView android:text="\?" android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/tv_number_one"
    android:textSize="30sp"
    android:textIsSelectable="true"
    android:layout_marginLeft="10dp"
    android:textColor="#67ceff"
    android:layout_marginStart="20dp"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="\?"
    android:id="@+id/tv_number_two"
    android:layout_alignBottom="@+id/tv_number_one"
    android:layout_toRightOf="@+id/tv_number_one"
    android:layout_toEndOf="@+id/tv_number_one"
    android:textColor="#67ceff"
    android:textSize="30sp"
    android:layout_marginLeft="20dp"
    android:layout_marginStart="20dp"
    />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="\?"
    android:id="@+id/tv_number_three"
    android:layout_alignParentTop="true"
    android:layout_toRightOf="@+id/tv_number_two"
    android:layout_toEndOf="@+id/tv_number_two"
    android:layout_marginLeft="20dp"
    android:textColor="#67ceff"
    android:textSize="30sp"
    android:layout_marginStart="20dp"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="\?"
    android:id="@+id/tv_number_four"
    android:layout_alignParentTop="true"
    android:layout_toRightOf="@+id/tv_number_three"
    android:layout_toEndOf="@+id/tv_number_three"
    android:textColor="#67ceff"
    android:textSize="30sp"
    android:textIsSelectable="true"
    android:layout_marginLeft="20dp"
    android:layout_marginStart="20dp"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="\?"
    android:id="@+id/tv_number_five"
    android:layout_alignParentTop="true"
    android:layout_toRightOf="@+id/tv_number_four"
    android:layout_toEndOf="@+id/tv_number_four"
    android:layout_marginLeft="20dp"
    android:textColor="#67ceff"
    android:textSize="30sp"
    android:layout_marginStart="20dp"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="\?"
    android:id="@+id/tv_number_six"
    android:layout_alignBottom="@+id/tv_number_five"
    android:layout_toRightOf="@+id/tv_number_five"
    android:layout_toEndOf="@+id/tv_number_five"
    android:textColor="#67ceff"
    android:textSize="30sp"
    android:layout_marginLeft="20dp"
    android:layout_marginStart="20dp"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="\?"
    android:id="@+id/tv_number_seven"
    android:layout_alignParentTop="true"
    android:layout_toRightOf="@+id/tv_number_six"
    android:layout_toEndOf="@+id/tv_number_six"
    android:layout_marginLeft="20dp"
    android:textColor="#6198ff"
    android:textSize="30sp"
    android:layout_marginStart="20dp"/>

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="NEXT NUMBER"
    android:id="@+id/button_next_num"
    android:layout_below="@+id/tv_number_one"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginTop="41dp"
    android:onClick="generate"/>

<Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="CLEAR"
    android:id="@+id/button_clear"
    android:onClick="clear"
    android:layout_alignTop="@+id/button_next_num"
    android:layout_toRightOf="@+id/tv_number_six"
    android:layout_toEndOf="@+id/tv_number_six"
    android:layout_marginLeft="30dp" />

Answer 1

编辑：根据您更新的问题

增加count作为你做的最后一件事。

// check if the count is too high first
if (count >= 7) {
    // desired behaviour if count is too high
    // clear(); //?
}

num[count] = myRandom.nextInt(48) + 1;
views[count].setText(String.valueOf(num[count]));
count++;

<强>原始

抱歉，我一开始并不理解这个问题。

我会创建一个TextView列表，并维护一个应用程序所在数字的计数器。

TextView[] views = new TextView[7];
int[] randomNumbers = new int[7];
int counter = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    views[0] = (TextView) findViewById(R.id.tv_number_one);
    views[1] = (TextView) findViewById(R.id.tv_number_two);
    // etc, etc
}

下一个按钮监听器

@Override
public void onClick(View v) {
    // check if there are any more numbers required (don't want to cause a NPE)

    // generate a new random number
    // check if it is unique in the list
    // if not generate a new number and repeat

    // when you have a unique number save it to
    // randomNumbers[counter] and display it in views[counter]
    // increment the counter
}

清除按钮侦听器

@Override
public void onClick(View v) {
    // clear list, clear views, reset counter
    randomNumbers = new int[7];
    for (TextView tv : views) tv.setText("?");
    counter = 0;
}

在Android中随机生成

1 个答案: