第四次作业

<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="com.example.homework3.MainActivity" >

     <TextView
        android:id="@+id/tv1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_marginTop="52dp"
        android:layout_toLeftOf="@+id/tv3"
        android:text="输入第一个数"
        android:textSize="20sp" />
    <TextView
        android:id="@+id/tv2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/tv1"
        android:layout_below="@+id/tv1"
        android:layout_marginTop="30dp"
        android:text="输入第二个数"
        android:textSize="20sp" />

    <EditText
        android:id="@+id/et2"
        android:layout_width="100sp"
        android:layout_height="wrap_content"
        android:layout_alignBottom="@+id/tv2"
        android:layout_toRightOf="@+id/bt1"
        android:ems="10"
        android:phoneNumber="true"
        android:textSize="20sp" />
     <EditText
        android:id="@+id/et1"
        android:layout_width="100sp"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/tv1"
        android:layout_alignBottom="@+id/tv1"
        android:layout_toRightOf="@+id/bt1"
        android:ems="10"
        android:phoneNumber="true"
        android:textSize="20sp" />

    <RadioGroup
        android:id="@+id/rg"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:orientation="horizontal" >

        <RadioButton
            android:id="@+id/rb2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="-   "
            android:textSize="25dp" />

        <RadioButton
            android:id="@+id/rb3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignLeft="@+id/tv2"
            android:layout_centerVertical="true"
            android:text="*   "
            android:textSize="25dp" />
         <RadioButton
           android:id="@+id/rb1"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:layout_centerVertical="true"
           android:layout_marginRight="21dp"
           android:layout_toLeftOf="@+id/bt1"
           android:text="+   "
           android:textSize="25dp" />

            <RadioButton
           android:id="@+id/rb4"
           android:layout_width="wrap_content"
           android:layout_height="wrap_content"
           android:layout_alignLeft="@+id/ed2"
           android:layout_centerVertical="true"
           android:text="/   "
           android:textSize="25dp" />
         </RadioGroup>

   

    <Button
        android:id="@+id/bt1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="80dp"
        android:onClick="remove"
        android:text="清除" />

    <TextView
        android:id="@+id/tv3"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/bt1"
        android:layout_centerHorizontal="true"
        android:text=""
        android:textSize="25dp" />

</RelativeLayout>

package com.example.xf;

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity implements
        RadioGroup.OnCheckedChangeListener {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        RadioGroup rg = (RadioGroup) findViewById(R.id.rg);
        rg.setOnCheckedChangeListener(this);
    }

    public void remove(View v) {
            TextView tv3 = (TextView) findViewById(R.id.tv3);
            EditText et1 = (EditText) findViewById(R.id.et1);
            EditText et2 = (EditText) findViewById(R.id.et2);
            switch (v.getId()) {
            case R.id.bt1:
                tv3.setText("");
                et1.setText("");
                et2.setText("");
                break;
            default:
                break;
            }
        
    }

    @Override
    public void onCheckedChanged(RadioGroup group, int checkedId) {
        try {
            EditText et1 = (EditText) findViewById(R.id.et1);
            EditText et2 = (EditText) findViewById(R.id.et2);
            TextView tv3 = (TextView) findViewById(R.id.tv3);
            String s1 = et1.getText().toString();
            String s2 = et2.getText().toString();
            double x = Double.parseDouble(s1);
            double y =Double.parseDouble(s2) ;
            switch (checkedId) {
            case R.id.rb1:
                double b1 = x + y;
                tv3.setText(""+b1);
                break;
            case R.id.rb2:
                double b2 = x - y;
                tv3.setText(""+b2);
                break;
            case R.id.rb3:
                double b3 = x * y;
                tv3.setText(""+b3);
                break;
            case R.id.rb4:
                double b4 = x / y;
                tv3.setText(""+b4);
                break;
            default:
                break;
            }
        } catch (Exception e) {
            Toast.makeText(MainActivity.this, "请输入数据", 0).show();
        }
    }
}