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) + "");
    }
}