Question

我试图在Android Studio中将十进制数分为整数和点数

Button btSpilt;
EditText Input;
TextView wholenumber, points;


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

    wholenumber = (TextView) findViewById(R.id.wholenumber);
    points = (TextView) findViewById(R.id.points);
    Input = (EditText) findViewById(R.id.Input);
    btSpilt = (Button) findViewById(R.id.btSpilt);

    btSpilt = findViewById(R.id.btSpilt);
    btSpilt.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            String s_input = Input.getText().toString();

            double input = Double.parseDouble(s_input);
            int a = Integer.parseInt(s_input);
            double aa = a;
            double b = (10 * input - 10 * input)/10;

            String str_a = Integer.toString((int) aa);
            String str_b = Integer.toString((int) b);

            wholenumber.setText(str_a);
            points.setText(str_b);
        }
    });

在输入整数时效果很好，但是在输入小数时整个应用程序崩溃

Answer 1

Math.floor()将帮助您：https://docs.oracle.com/javase/7/docs/api/java/lang/Math.html#floor(double)

        double input = Double.parseDouble(s_input);
        double wholeNumber = Math.floor(input);
        double afterDecimal = input - wholeNumber;

Answer 2

int a = Integer.parseInt(s_input);//this line caused error when s_input represents decimal.
double b = (10 * input - 10 * input)/10;//b always equal zero

要获得双精度的整数和小数部分，可以尝试使用split

                String s_input = Input.getText().toString();
                if (s_input.contains(".")) {
                    String[] split = s_input.split("\\.");
                    String whole = split[0];
                    String fractional = split[1];
                }

在Android Studio中将双精度分隔为整数和十进制部分

2 个答案: