Question

我正在尝试构建一个BMI计算器应用程序，但是，使用intent和方法getIntExtra（）似乎有问题，因为我总是得到默认值而不是我从另一个活动传入的值。以下是我的第一个活动的代码

    calculate.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent intent = new Intent(getApplicationContext(), SecondActivity.class);

            int weight = Integer.parseInt(weightText.getText().toString());
            int height = Integer.parseInt(heightText.getText().toString());

            intent.putExtra(USER_WEIGHT_EXTRA, weight);
            intent.putExtra(USER_HEIGHT_EXTRA, height);
            startActivity(intent);
        }
    });

第二项活动双height2 = (double)height/100的原因是从cm转换为m。

    result = (TextView)findViewById(R.id.result);
    todo = (TextView) findViewById(R.id.todo);

    Intent intent = getIntent();

    int weight = intent.getIntExtra("USER_WEIGHT_EXTRA", extraInt);
    int height = intent.getIntExtra("USER_HEIGHT_EXTRA", extraInt);

    double height2 = (double)height/100;
    double BMI = (weight*1.0)/(height2*height2);


    if (BMI < 20.0) {
        result.setText("You are: UNDERWEIGHT");
        todo.setText("You Should EAT MORE");
    } else if (BMI > 20.0 && BMI < 25.0) {
        result.setText("You are: NORMAL WEIGHT");
        todo.setText("You Should keep STAYING HEALTHY");
    } else if (BMI > 25) {
        result.setText("You are: OVERWEIGHT");
        todo.setText("You Should EXERCISE MORE");
    }
}

我真的被困在这个问题上了。非常感谢你们！

Answer 1

在第一项活动中

 Intent in = new Intent(this, OtherActivity.class);
            in.putExtra("USER_WEIGHT_EXTRA", weightText.getText().toString());
            in.putExtra("USER_HEIGHT_EXTRA", heightText.getText().toString());
            startActivity(in);`

for otherActivity

Bundle bundle = getIntent().getExtras();

        int weight = Integer.parseInt(bundle.getString("USER_WEIGHT_EXTRA"));
        int height = Integer.parseInt(bundle.getString("USER_HEIGHT_EXTRA"));

Android BMI计算器App意图错误

1 个答案: