应用突然挂起-构建用于随机数减法的应用

Question

我正在为我的女儿构建数学应用程序 一切都很好-加，乘，除，间，升等

但是在第一次加载时减去它，第二次将应用程序挂起-我必须直接退出它，从ram中清除它，然后每次重新启动

日志猫未显示任何错误或夜间警告， 请指导我-我是初学者（实际上是第一个应用）

我的代码

@Bean(name = "GemfireClientProperties")
Properties gemfireClientProperties() {
    Properties gemfireProperties = new Properties();
    gemfireProperties.setProperty("mcast-port", "0");
    gemfireProperties.setProperty("log-level", "config");
    return gemfireProperties;
}


@Bean(name = "GemfireClientPool")
PoolFactoryBean gemfireClientPool() {
    PoolFactoryBean gemfirePool = new PoolFactoryBean();
    gemfirePool.setRetryAttempts(1);
    gemfirePool.setLocators(Collections.singletonList(new ConnectionEndpoint("localhost", 17202)));
    return gemfirePool;
}


@Bean(name = "clientCache")
ClientCache clientCache(@Qualifier("GemfireClientProperties") Properties gemfireClientProperties) {
    ClientCacheFactory clientCacheFactory = new ClientCacheFactory(gemfireClientProperties);
    return clientCacheFactory.create();
}

GlobalOverride类。

    package youtube.computers.mohammedi.kidsmath;

    import android.os.Bundle;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.TextView;
    import android.widget.Toast;
    import com.google.android.gms.ads.AdRequest.Builder;
    import com.google.android.gms.ads.AdView;
    import java.util.Random;

    public class Subtract extends GlobalOverride implements OnClickListener {
        int ans;
        Button btn1;
        Button btn2;
        Button btn3;
        Button btn4;
        int max;
        int n1;
        int n2;
        Random f16r;
        int temp;
        TextView txt_add;
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView((int) R.layout.activity_subtract);
        setTitle("Subtraction");
        this.btn1 =  findViewById(R.id.btn1);
        this.btn2 =  findViewById(R.id.btn2);
        this.btn3 =  findViewById(R.id.btn3);
        this.btn4 =  findViewById(R.id.btn4);
        this.txt_add = (TextView) findViewById(R.id.txt_ascen);
        this.btn1.setOnClickListener(this);
        this.btn2.setOnClickListener(this);
        this.btn3.setOnClickListener(this);
        this.btn4.setOnClickListener(this);
        this.max = getSharedPreferences("Math", 0).getInt("add", 10);
        ((AdView) findViewById(R.id.adView)).loadAd(new Builder().build());
        generate();
    }

    public void onClick(View v) {
        this.ans = Integer.parseInt((String) ((Button) v).getText());
        if (this.ans == this.temp) {
            generate();
        } else {
            Toast.makeText(this, "Incorrect", Toast.LENGTH_SHORT).show();
        }
    }

    public void generate() {
        this.n1 = GlobalOverride.getRand(1, this.max);
        this.n2 = GlobalOverride.getRand(1, this.max);
        if(n2>n1 && max<=20){
            generate();
        }
        this.temp = this.n1 - this.n2;
        this.txt_add.setText(this.n1 + " - " + this.n2 + " = ?");
        int[] answer = new int[4];
        int count = 0;
        while (count <= 3) {
            int random_integer = GlobalOverride.getRand(this.temp - 2, this.temp + 2);
            if (!exists(random_integer, answer)) {
                answer[count] = random_integer;
                count++;
            }
        }
        if (!exists(this.temp, answer)) {
            answer[GlobalOverride.getRand(0, 3)] = this.temp;
        }
        this.btn1.setText(String.valueOf(answer[0]));
        this.btn2.setText(String.valueOf(answer[1]));
        this.btn3.setText(String.valueOf(answer[2]));
        this.btn4.setText(String.valueOf(answer[3]));
    }

    public boolean exists(int number, int[] array) {
        if (number == -1) {
            return true;
        }
        for (int i : array) {
            if (number == i) {
                return true;
            }
        }
        return false;
        }
    }

布局输出

Answer 1

我不明白为什么您要在第一个if语句中递归调用generate（）。我的怀疑是，这不是您想要的。您可能最终需要进行几层递归。 您可能想要在代码中添加一些注释，这将使理解变得更加容易。

如果您不想要负数，只需交换两个整数即可，而不用调用generate（）：

if(n2>n1 && max<=20){
    int swap = n1;
    n1 = n2;
    n2 = swap;
}