Android开发实现的标准体重计算器功能示例

<RelativeLayout xmlns:tools="http://schemas.android.com/tools"
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:paddingBottom="@dimen/activity_vertical_margin"
  android:paddingLeft="@dimen/activity_horizontal_margin"
  android:paddingRight="@dimen/activity_horizontal_margin"
  android:paddingTop="@dimen/activity_vertical_margin"
  tools:context=".MainActivity" >
  <TextView
    android:id="@+id/textView2"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_alignParentTop="true"
    android:layout_marginTop="17dp"
    android:text="@string/hello_world" />
  <TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:layout_marginLeft="18dp"
    android:layout_marginTop="68dp"
    android:text="@string/sex" />
  <RadioGroup
    android:id="@+id/radioGroup1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignTop="@+id/textView1"
    android:layout_marginLeft="25dp"
    android:layout_toRightOf="@+id/textView1" >
    <RadioButton
      android:id="@+id/radio0"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:text="@string/sex1" />
    <RadioButton
      android:id="@+id/radio1"
      android:layout_width="wrap_content"
      android:layout_height="wrap_content"
      android:text="@string/sex2" />
  </RadioGroup>
  <TextView
    android:id="@+id/TextView01"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_centerVertical="true"
    android:text="@string/high" />
  <EditText
    android:id="@+id/editText1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerVertical="true"
    android:layout_toRightOf="@+id/TextView01"
    android:ems="10"
    android:inputType="number" >
    <requestFocus />
  </EditText>
  <Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@+id/editText1"
    android:layout_marginTop="72dp"
    android:layout_toRightOf="@+id/textView2"
    android:onClick="ClickHandler"
    android:text="@string/calculate" />
</RelativeLayout>

package org.wwj.calculate;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.Toast;
public class MainActivity extends Activity {
  //定义各个组件
  private Button cal;
  private EditText high;
  private RadioGroup sex;
  private RadioButton sex1;
  private RadioButton sex2;
  private Double weight;
  String sex3;
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //通过findViewById获取对象
    cal=(Button) this.findViewById(R.id.button1);
    high=(EditText) this.findViewById(R.id.editText1);
    sex=(RadioGroup) this.findViewById(R.id.radioGroup1);
    sex1=(RadioButton) this.findViewById(R.id.radio0);
    sex2=(RadioButton) this.findViewById(R.id.radio1);
    //设置Button事件监听
    cal.setOnClickListener(new OnClickListener() {
      public void onClick(View v) {
        /*设置事件监听*/
        sex.setOnCheckedChangeListener(new OnCheckedChangeListener() {
          @Override
          public void onCheckedChanged(RadioGroup group, int checkedId) {
            //事件处理
            if(checkedId==sex1.getId()){
              weight=(Double.parseDouble(high.getText().toString()) - 80) * 0.7;
              sex3="男性";
            }else if(checkedId==sex2.getId()){
              weight=(Double.parseDouble(high.getText().toString()) - 70) * 0.6;
              sex3="女性";
            }
          }
        });
        /*Toast显示内容*/
        Toast.makeText(MainActivity.this, "你是一位"+sex3+"\n"
            +"你的身高是"+high.getText().toString()+"\n"+"你的标准体重是"+weight,
            Toast.LENGTH_LONG).show();
      }
    });
  }
  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
  }
}