Question

我想在Android中创建一个简单的计算器，以我的方式出现调用功能时出错，我已经声明了。这里的任何Android专家都可以帮到我吗？

public class CalculatorActivity extends AppCompatActivity {

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

    //Start my method

    public void calculator(View v) {
        Button btn0 = (Button) findViewById(R.id.btn0);
        Button btn1 = (Button) findViewById(R.id.btn1);
        Button btn2 = (Button) findViewById(R.id.btn2);
        Button btn3 = (Button) findViewById(R.id.btn3);
        Button btn4 = (Button) findViewById(R.id.btn4);
        Button btn5 = (Button) findViewById(R.id.btn5);
        Button btn6 = (Button) findViewById(R.id.btn6);
        Button btn7 = (Button) findViewById(R.id.btn7);

        TextView textViewResult = (TextView) findViewById(R.id.textView);

        if (btn0.isPressed() == true) {

            textViewResult.setText(textViewResult + "0");
        } else if (btn1.isPressed() == true) {
            textViewResult.setText(textViewResult + "1");

        }

    }
       //End my method

    //I want to call that fucntion, and i get an error
    calculator();


}

Answer 1

您应该在OnCreate()

中调用该方法

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

Answer 2

试试这个

public class CalculatorActivity extends AppCompatActivity {

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

    //Start my method

    public void calculator() {
        Button btn0 = (Button) findViewById(R.id.btn0);
        Button btn1 = (Button) findViewById(R.id.btn1);
        Button btn2 = (Button) findViewById(R.id.btn2);
        Button btn3 = (Button) findViewById(R.id.btn3);
        Button btn4 = (Button) findViewById(R.id.btn4);
        Button btn5 = (Button) findViewById(R.id.btn5);
        Button btn6 = (Button) findViewById(R.id.btn6);
        Button btn7 = (Button) findViewById(R.id.btn7);

        TextView textViewResult = (TextView) findViewById(R.id.textView);

        if (btn0.isPressed() == true) {

            textViewResult.setText(textViewResult + "0");
        } else if (btn1.isPressed() == true) {
            textViewResult.setText(textViewResult + "1");

        }

    }
       //End my method
}

Answer 3

使用以下代码：

public class CalculatorActivity extends AppCompatActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_calculator);
        //I want to call that fucntion, and i get an error
        calculator();
        }

        //Start my method

        public void calculator() {
            Button btn0 = (Button) findViewById(R.id.btn0);
            Button btn1 = (Button) findViewById(R.id.btn1);
            Button btn2 = (Button) findViewById(R.id.btn2);
            Button btn3 = (Button) findViewById(R.id.btn3);
            Button btn4 = (Button) findViewById(R.id.btn4);
            Button btn5 = (Button) findViewById(R.id.btn5);
            Button btn6 = (Button) findViewById(R.id.btn6);
            Button btn7 = (Button) findViewById(R.id.btn7);

            TextView textViewResult = (TextView) findViewById(R.id.textView);

            if (btn0.isPressed() == true) {

                textViewResult.setText(textViewResult + "0");
            } else if (btn1.isPressed() == true) {
                textViewResult.setText(textViewResult + "1");

            }

        }
           //End my method
    }

Answer 4

在onCreate（）方法中调用calculator（）方法

Answer 5

致电计算器（）;在你的onCreate（）

里面

   public class CalculatorActivity extends AppCompatActivity {

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

    //Start my method

    public void calculator(View v) {
        Button btn0 = (Button) findViewById(R.id.btn0);
        Button btn1 = (Button) findViewById(R.id.btn1);
        Button btn2 = (Button) findViewById(R.id.btn2);
        Button btn3 = (Button) findViewById(R.id.btn3);
        Button btn4 = (Button) findViewById(R.id.btn4);
        Button btn5 = (Button) findViewById(R.id.btn5);
        Button btn6 = (Button) findViewById(R.id.btn6);
        Button btn7 = (Button) findViewById(R.id.btn7);

        TextView textViewResult = (TextView) findViewById(R.id.textView);

        if (btn0.isPressed() == true) {

            textViewResult.setText(textViewResult + "0");
        } else if (btn1.isPressed() == true) {
            textViewResult.setText(textViewResult + "1");

        }

    }
}

现在它正在开展工作魅力

如何在android中调用方法，以便能够运行代码

5 个答案: