Question

我的基本数字是0-9，而我的代码是

    public class MainActivity extends AppCompatActivity {


    Button button0 , button1 , button2 , button3 , button4 , button5 , button6 ,
            button7 , button8 , button9 , buttonAdd , buttonSub , buttonDivision,
            buttonMul , button10 , buttonC , buttonEqual ;

    TextView txtView ;

    float num1 = 0;
    float num2 = 0;
    float sum = 0;


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

            button0 = (Button) findViewById(R.id.button0);
            button1 = (Button) findViewById(R.id.button1);
            button2 = (Button) findViewById(R.id.button2);
            button3 = (Button) findViewById(R.id.button3);
            button4 = (Button) findViewById(R.id.button4);
            button5 = (Button) findViewById(R.id.button5);
            button6 = (Button) findViewById(R.id.button6);
            button7 = (Button) findViewById(R.id.button7);
            button8 = (Button) findViewById(R.id.button8);
            button9 = (Button) findViewById(R.id.button9);
            button10 = (Button) findViewById(R.id.button10);
            buttonAdd = (Button) findViewById(R.id.buttonadd);
            buttonSub = (Button) findViewById(R.id.buttonsub);
            buttonMul = (Button) findViewById(R.id.buttonmul);
            buttonDivision = (Button) findViewById(R.id.buttondiv);
            buttonC = (Button) findViewById(R.id.buttonC);
            buttonEqual = (Button) findViewById(R.id.buttoneql);
            txtView = (TextView) findViewById(R.id.txtView);


            button1.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txt.setText(txt.getText()+"1");
                }
            });

            button2.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"2");
                }
            });

            button3.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"3");
                }
            });

            button4.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"4");
                }
            });

            button5.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"5");
                }
            });

            button6.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"6");
                }
            });

            button7.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"7");
                }
            });

            button8.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"8");
                }
            });

            button9.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(txtView.getText()+"9");
                }
            });

然而，当我尝试执行添加功能时，应用程序崩溃了。这似乎很简单，但我见过的其他例子更复杂。我的附加代码是......

    buttonAdd.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    num1 = Float.parseFloat(txtView.getText().toString());
                    num2 = Float.parseFloat(txtView.getText().toString());
                    sum = num1 + num2;
                }
            });

然后当按下相等按钮时，我的代码如下。这是对我不起作用的部分。

 buttonEqual.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    txtView.setText(Float.toString(sum));
                }
            });

这导致应用程序崩溃。有帮助吗？感谢

Answer 1

我认为你的buttonAdd功能是错误的。

num1 = Float.parseFloat(txtView.getText().toString());
num2 = Float.parseFloat(txtView.getText().toString());

执行代码时，num1和num2相同。

Answer 2

我不明白你的错误。但没有问题，只需要改变btnAdd和btnEqual 你能试试吗？

base-4.5

Android基本计算器，加，减，乘，除

2 个答案: