使用 KOTLIN android studio 进行 JUnit 测试 [基本计算器]

Question

我对 android 开发非常陌生，最近做了我的第一个项目。它只是一个基本的计算器，有加减乘除。

现在，我希望通过 KOTLIN 使用 JUnit 进行单元测试。我该怎么做呢？我一直在四处寻找，不知道。

计算器 Java 代码：

package com.example.zhiwen.calculator;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity{

Button plus,minus,times,divide;
TextView textview3;
EditText first, second;
double no1 = 0, no2 = 0;
double answer = 0;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    plus = (Button) findViewById(R.id.plus);
    minus = (Button) findViewById(R.id.minus);
    times = (Button) findViewById(R.id.times);
    divide = (Button) findViewById(R.id.divide);
    textview3 = (TextView) findViewById(R.id.textview3);
    first = (EditText) findViewById(R.id.editText);
    second = (EditText) findViewById(R.id.editText2);


}

public void ClickMeButton(View view){
    if(first.getText().toString().isEmpty() || second.getText().toString().isEmpty())
    {
        textview3.setText("Answer: -");
        Toast.makeText(getApplicationContext(),"Please fill up both numbers",Toast.LENGTH_SHORT).show();
    }
    else
    {
        no1 = Integer.parseInt(first.getText().toString());
        no2 = Integer.parseInt(second.getText().toString());
        textview3.setText("Answer: " + Functions.addFunction(no1,no2));
    }

}



public void ClickMeButton2(View view){
    if(first.getText().toString().isEmpty() || second.getText().toString().isEmpty())
    {
        textview3.setText("Answer: -");
        Toast.makeText(getApplicationContext(),"Please fill up both numbers",Toast.LENGTH_SHORT).show();
    }
    else
    {
        no1 = Integer.parseInt(first.getText().toString());
        no2 = Integer.parseInt(second.getText().toString());
        textview3.setText("Answer: " + Functions.minusFunction(no1,no2));
    }

}
public void ClickMeButton3(View view){
    if(first.getText().toString().isEmpty() || second.getText().toString().isEmpty())
    {
        textview3.setText("Answer: -");
        Toast.makeText(getApplicationContext(),"Please fill up both numbers",Toast.LENGTH_SHORT).show();
    }
    else
    {
        no1 = Integer.parseInt(first.getText().toString());
        no2 = Integer.parseInt(second.getText().toString());
        textview3.setText("Answer: " + Functions.multiFunction(no1,no2));
    }

}
public void ClickMeButton4(View view){
    if(first.getText().toString().isEmpty() || second.getText().toString().isEmpty())
    {
        textview3.setText("Answer: -");
        Toast.makeText(getApplicationContext(),"Please fill up both numbers",Toast.LENGTH_SHORT).show();
    }
    else
    {
        no1 = Integer.parseInt(first.getText().toString());
        no2 = Integer.parseInt(second.getText().toString());
        textview3.setText("Answer: " + Functions.divFunction(no1,no2));
    }

}

}

函数类代码：

package com.example.zhiwen.calculator;

/**
 * Created by Zhiwen on 5/25/2017.
 */

public class Functions {

public static double addFunction(double no1, double no2){
    double answer;
    answer = no1 + no2;
    return answer;
}

public static double minusFunction(double no1, double no2){
    double answer;
    answer = no1 - no2;
    return answer;
}

public static double multiFunction(double no1, double no2){
    double answer;
    answer = no1 * no2;
    return answer;
}

public static double divFunction(double no1, double no2){
    double answer;
    answer = no1 / no2;
    return answer;
}

}

Answer 1

您不能对此类代码使用单元测试。 你有两个选择：

1. 将计算器的业务逻辑提取到不相关的类中 Android 框架并使用单元测试测试此类
2. 使用 Instrumentation 测试和 Espresso 测试 UI

第一个选项更可取（单元测试更快，您将拥有更好的架构）。

在这种情况下，使用 Java 或 Kotlin 进行测试没有区别，您应该使用与 Java 完全相同的方法和技术。

所以你应该做的第一件事是在 Android 开发者网站上查看官方培训 - https://developer.android.com/training/testing/index.html