<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" > <TextView android:id="@+id/tv2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignLeft="@+id/et2" android:layout_centerVertical="true" android:gravity="center" android:text="显示计算结果" android:textStyle="italic" /> <EditText android:id="@+id/et3" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_below="@+id/tv2" android:layout_alignLeft="@+id/et1" android:ems="10" > <requestFocus /> </EditText> <EditText android:id="@+id/et1" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_below="@+id/et3" android:layout_alignLeft="@+id/tv1" android:hint="请输入数值" android:ems="10" /> <EditText android:id="@+id/et2" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_below="@+id/et1" android:layout_alignLeft="@+id/tv1" android:hint="请输入数值" android:ems="10" /> <Button android:id="@+id/sum" android:layout_width="152dp" android:layout_height="wrap_content" android:editable="false" android:text="+" /> <Button android:id="@+id/reduce" android:layout_width="152dp" android:layout_height="wrap_content" android:layout_toRightOf="@+id/sum" android:text="-" android:textSize="20sp" /> <Button android:id="@+id/ride" android:layout_width="152dp" android:layout_height="wrap_content" android:layout_below="@+id/sum" android:text="X" /> <Button android:id="@+id/except" android:layout_width="152dp" android:layout_height="wrap_content" android:layout_below="@+id/reduce" android:layout_toRightOf="@+id/ride" android:text="/" /> </RelativeLayout>
package com.example.aaaa; 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.TextView; import android.widget.Toast; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } public void click(View v) { TextView tv2 = (TextView) findViewById(R.id.tv2); EditText et1 = (EditText) findViewById(R.id.et1); EditText et2 = (EditText) findViewById(R.id.et2); int num1,num2,result=0; num1=Integer.parseInt(et1.getText().toString()); num2=Integer.parseInt(et2.getText().toString()); switch (v.getId()) { case R.id.sum: result=num1+num2; break; case R.id.reduce: result=num1-num2; break; case R.id.ride: result=num1*num2; break; case R.id.except: result=num1/num2; break; } tv2.setText(result+""); } }