java - 在 Android Studio 中创建一个计算器。但我希望计算在一个文本视图中，并将结果发布在结果文本视图中

Question

我希望仅在一个文本视图中进行计算，并将结果发布在结果文本视图中。但我正在努力将数字相加有没有办法在一个文本视图中进行计算？

public class MainActivity extends AppCompatActivity {
    private TextView results, calculationField;

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

        TextView calculationField = (TextView) findViewById(R.id.calculationField);
        TextView results = (TextView) findViewById(R.id.results);
        Button button0 = (Button) findViewById(R.id.button0);
        Button button1 = (Button) findViewById(R.id.button1);
        Button button2 = (Button) findViewById(R.id.button2);
        Button button3 = (Button) findViewById(R.id.button3);
        Button button4 = (Button) findViewById(R.id.button4);
        Button button5 = (Button) findViewById(R.id.button5);
        Button button6 = (Button) findViewById(R.id.button6);
        Button button7 = (Button) findViewById(R.id.button7);
        Button button8 = (Button) findViewById(R.id.button8);
        Button button9 = (Button) findViewById(R.id.button9);
        Button buttonDot = (Button) findViewById(R.id.buttonDot);

        Button buttonDivide = (Button) findViewById(R.id.buttonDivide);
        Button buttonMultiply = (Button) findViewById(R.id.buttonMultiply);
        Button buttonPlusMinus = (Button) findViewById(R.id.buttonPlusMinus);
        Button buttonPercentage = (Button) findViewById(R.id.buttonPercentage);
        Button buttonPlus = (Button) findViewById(R.id.buttonPlus);
        Button buttonMinus = (Button) findViewById(R.id.buttonMinus);
        Button buttonEquals = (Button) findViewById(R.id.buttonEquals);
        Button buttonReset = (Button) findViewById(R.id.buttonReset);

        View.OnClickListener numberButtons = new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switch (v.getId()) {
                    case R.id.button0:
                        calculationField.append(button0.getText().toString());
                        break;
                    case R.id.button1:
                        calculationField.append(button1.getText().toString());
                        break;
                    case R.id.button2:
                        calculationField.append(button2.getText().toString());
                        break;
                    case R.id.button3:
                        calculationField.append(button3.getText().toString());
                        break;
                    case R.id.button4:
                        calculationField.append(button4.getText().toString());
                        break;
                    case R.id.button5:
                        calculationField.append(button5.getText().toString());
                        break;
                    case R.id.button6:
                        calculationField.append(button6.getText().toString());
                        break;
                    case R.id.button7:
                        calculationField.append(button7.getText().toString());
                        break;
                    case R.id.button8:
                        calculationField.append(button8.getText().toString());
                        break;
                    case R.id.button9:
                        calculationField.append(button9.getText().toString());
                        break;
                    case R.id.buttonDot:
                        calculationField.append(buttonDot.getText().toString());
                        break;
                }
            }
        };

        button0.setOnClickListener(numberButtons);
        button1.setOnClickListener(numberButtons);
        button2.setOnClickListener(numberButtons);
        button3.setOnClickListener(numberButtons);
        button4.setOnClickListener(numberButtons);
        button5.setOnClickListener(numberButtons);
        button6.setOnClickListener(numberButtons);
        button7.setOnClickListener(numberButtons);
        button8.setOnClickListener(numberButtons);
        button9.setOnClickListener(numberButtons);
        buttonDot.setOnClickListener(numberButtons);

        View.OnClickListener symbolslistener = new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                switch (v.getId()) {
                    case R.id.buttonReset:
                        calculationField.setText("");
                        results.setText("");
                        break;
                    case R.id.buttonPlusMinus:
                        calculationField.append(buttonPlusMinus.getText().toString());
                        break;
                    case R.id.buttonPercentage:
                        calculationField.append(buttonPercentage.getText().toString());
                        break;
                    case R.id.buttonDivide:
                        calculationField.append(buttonDivide.getText().toString());
                        break;
                    case R.id.buttonMultiply:
                        calculationField.append(buttonMultiply.getText().toString());
                        break;
                    case R.id.buttonMinus:
                        calculationField.append(buttonMinus.getText().toString());
                        break;
                    case R.id.buttonPlus:
                        calculationField.append(buttonPlus.getText().toString());
                        break;
                    case R.id.buttonEquals:
                        results.setText(buttonEquals.getText().toString());
                        break;
                }
            }
        };
        buttonReset.setOnClickListener(symbolslistener);
        buttonPlusMinus.setOnClickListener(symbolslistener);
        buttonPercentage.setOnClickListener(symbolslistener);
        buttonDivide.setOnClickListener(symbolslistener);
        buttonMultiply.setOnClickListener(symbolslistener);
        buttonMinus.setOnClickListener(symbolslistener);
        buttonPlus.setOnClickListener(symbolslistener);
        buttonEquals.setOnClickListener(symbolslistener);
    }
}

标签： javaandroid