<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" 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" > <EditText android:id="@+id/EditText01" android:layout_width="200dp" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:layout_below="@+id/editText2" android:layout_marginTop="20dp" android:ems="10" /> <TextView android:id="@+id/TextView01" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignBottom="@+id/EditText01" android:layout_toLeftOf="@+id/EditText01" android:text="输入第二个数" /> <EditText android:id="@+id/editText2" android:layout_width="200dp" android:layout_height="wrap_content" android:layout_alignLeft="@+id/EditText01" android:layout_alignParentTop="true" android:ems="10" /> <TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignBottom="@+id/editText2" android:layout_toLeftOf="@+id/editText2" android:text="输入第一个数" /> <TextView android:id="@+id/tv" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignTop="@+id/textView2" android:layout_centerHorizontal="true" /> <Button android:id="@+id/RE" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentBottom="true" android:layout_centerHorizontal="true" android:layout_marginBottom="53dp" android:onClick="click" android:text="清空" /> <TextView android:id="@+id/textView2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_above="@+id/RE" android:layout_alignLeft="@+id/TextView01" android:layout_marginBottom="78dp" android:text="计算结果是" /> <RadioGroup android:id="@+id/rdg" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_above="@+id/textView2" android:layout_alignLeft="@+id/textView2" android:orientation="vertical" > <RadioButton android:id="@+id/add" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_toRightOf="@+id/rdg" android:text="+" /> <RadioButton android:id="@+id/mul" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_toRightOf="@+id/minus" android:text="*" /> <RadioButton android:id="@+id/devide" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_toRightOf="@+id/mul" android:text="/" /> <RadioButton android:id="@+id/minus" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_toRightOf="@+id/add" android:text="-" /> </RadioGroup> </RelativeLayout> package com.example.jisuan; import com.example.jisuan.R; import com.example.jisuan.MainActivity; import android.os.Bundle; import android.app.Activity; import android.view.Menu; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.RadioGroup; import android.widget.TextView; import android.widget.Toast; import android.widget.RadioGroup.OnCheckedChangeListener; public class MainActivity extends Activity implements OnCheckedChangeListener { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); RadioGroup rg = (RadioGroup) findViewById(R.id.rdg); rg.setOnCheckedChangeListener(this); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } @Override public void onCheckedChanged(RadioGroup group, int checkedId) { EditText et1 = (EditText) findViewById(R.id.editText2); EditText et2 = (EditText) findViewById(R.id.EditText01); String s1 = et1.getText().toString(); String s2 = et2.getText().toString(); double num1 = Integer.valueOf(s1).intValue(); double num2 = Integer.valueOf(s2).intValue(); // TODO 自动生成的方法存根 TextView tv = (TextView) findViewById(R.id.tv); switch (checkedId) { case R.id.add: num1 = num1 + num2; s1 = String.valueOf(num1); tv.setText(s1); break; case R.id.minus: num1 = num1 - num2; s1 = String.valueOf(num1); tv.setText(s1); break; case R.id.mul: num1 = num1 * num2; s1 = String.valueOf(num1); tv.setText(s1); break; case R.id.devide: num1 = num1 / num2; s1 = String.valueOf(num1); tv.setText(s1); break; } } public void click(View view) { TextView tv = (TextView) findViewById(R.id.tv); TextView tv2 = (TextView) findViewById(R.id.editText2); ; TextView tv3 = (TextView) findViewById(R.id.EditText01); ; switch (view.getId()) { case R.id.RE: tv.setText(""); tv2.setText(""); tv3.setText(""); }