为什么这样写计算出来的BMI等于0

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="80dp"
        >
        <TextView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:text="BMI计算器"
            android:textSize="45sp"
            android:gravity="center"
            android:textColor="@color/colorPrimary"

            />
    LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_marginTop="10dp"
        >
       <TextView
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:text="身高(M):"
           android:textSize="25sp"
           />
        <EditText
            android:id="@+id/height"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="请输入您的身高"

            />
    LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        >
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="体重(KG):"
            android:textSize="25sp"
            />
        <EditText
            android:id="@+id/weight"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="请输入您的体重"
            />
    LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        >
        <Button
            android:id="@+id/btn"
            android:layout_marginTop="10dp"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="计算BMI"
            android:textSize="25sp"
            />
    LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_marginTop="10dp"
        >
        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="您的BMI指数为:"
            android:textSize="20sp"
            />
        <EditText
            android:id="@+id/bmi"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />
    LinearLayout>
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="300dp"
        android:layout_marginTop="10dp"
        >
        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/bmi"
            />
    LinearLayout>
LinearLayout>

```java
ackage com.example.myapplication;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.bmi);
        final EditText etHeight = findViewById(R.id.height);
        final EditText etWeight = findViewById(R.id.weight);
        final EditText etBmi = findViewById(R.id.bmi);
        Button button = findViewById(R.id.btn);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
//                String heightStr = etHeight.getText().toString();
//                String weightStr = etWeight.getText().toString();
//                if (!TextUtils.isEmpty(heightStr) && !TextUtils.isEmpty(weightStr)) {
                    double height = Double.parseDouble(etHeight.getText().toString());
                    System.out.println(height);
                    double weight = Double.parseDouble(etWeight.getText().toString());
                    System.out.println(weight);
                    double bmi = weight / (height * height);
                    System.out.println(bmi);
                    etBmi.setText(String.format("%2f",bmi));

//                }
            }
        });
    }
}

![img](https://img-mid.csdnimg.cn/release/static/image/mid/ask/594377605876126.png "#left")

。。。

体重/(身高*身高) = 1.76/(70*70)

你说是多少？
你奥特曼，身高70m?