ANDROID_MARS学习笔记_S01原始版_002_实现计算乘积及menu应用

一、代码

1.xml
(1)activity_main.xml

 <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.s01_original_e06_caculate.MainActivity" >

     <EditText
         android:id="@+id/m_multiplier"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:inputType="text"/>

     <EditText
         android:id="@+id/m_multiplicand"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_below="@id/m_multiplier"
         android:inputType="number"/>

     <Button
         android:id="@+id/caculateBtn"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:text="@string/caculate"
         android:layout_below="@id/m_multiplicand"/>

 </RelativeLayout>

(2)resultactivity.xml

 <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">

     <TextView
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:id="@+id/accumulateText"
         android:text="@string/app_name"/>

 </RelativeLayout>

2.java
(1)MainActivity.java

 package com.example.s01_original_e06_caculate;

 import android.app.Activity;
 import android.content.Intent;
 import android.os.Bundle;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.Button;
 import android.widget.EditText;

 public class MainActivity extends Activity {

     private Button caculateBtn = null;
     private EditText multiplierView = null;
     private EditText multiplicandViwe = null;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         multiplierView = (EditText) findViewById(R.id.m_multiplier);
         multiplicandViwe = (EditText) findViewById(R.id.m_multiplicand);
         caculateBtn = (Button) findViewById(R.id.caculateBtn);
         caculateBtn.setOnClickListener(new OnClickListener() {
             @Override
             public void onClick(View v) {
                 Intent intent = new Intent();
                 intent.putExtra("multiplier", multiplierView.getText().toString());
                 intent.putExtra("multiplicand", multiplicandViwe.getText().toString());
                 intent.setClass(MainActivity.this, ResultActivity.class);
                 MainActivity.this.startActivity(intent);
             }
         });
     }

     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
         menu.add(0, 1, 1, R.string.exit);
         menu.add(0, 2, 2, R.string.about);
         return super.onCreateOptionsMenu(menu);
     }

     @Override
     public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId()) {
         case 1:
             finish();
             return true;
         default:
             System.out.println("关于程序");
             break;
         }
         return super.onOptionsItemSelected(item);
     }
 }

(2)ResultActivity.java

 package com.example.s01_original_e06_caculate;

 import android.app.Activity;
 import android.content.Intent;
 import android.os.Bundle;
 import android.widget.TextView;

 public class ResultActivity extends Activity {

     private TextView accumulateTextView = null;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.resultactivity);

         accumulateTextView = (TextView) findViewById(R.id.accumulateText);
         Intent intent = getIntent();
         int multiplier = Integer.parseInt(intent.getStringExtra("multiplier"));
         int multiplicand = Integer.parseInt(intent.getStringExtra("multiplicand"));
         accumulateTextView.setText((multiplier * multiplicand) + "");
     }
 }