Android之文件操作和JUnit

1>写一个文件保存和读取的应用程序。和javaEE一样MVC的设计模式，在android里M应该是Service层，那么Service层和view层应该可以并行开发。因为程序比较简单，我就先写view了。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
	<TextView
		android:id="@+id/fileNameLabel"  
	    android:layout_width="fill_parent" 
	    android:layout_height="wrap_content" 
	    android:text="@string/fileNameLabel"
	    />
	<EditText
		android:id="@+id/fileNameEdit"  
	    android:layout_width="fill_parent" 
	    android:layout_height="wrap_content"
	    />
	<TextView
		android:id="@+id/fileTxtLabel"  
	    android:layout_width="fill_parent" 
	    android:layout_height="wrap_content" 
	    android:text="@string/fileTxtLabel"
	    />
	<EditText
		android:id="@+id/fileTxtEdit"  
	    android:layout_width="fill_parent"
	    android:minLines="3" 
	    android:layout_height="wrap_content"
	    />    
	<Button
		android:id="@+id/fileSaveBtn"  
	    android:layout_width="wrap_content" 
	    android:layout_height="wrap_content" 
	    android:text="@string/fileSaveBtn"
	    />

</LinearLayout>

2>然后是Service层。

package com.duantl.service;

import java.io.FileOutputStream;

import android.content.Context;

public class FileService {

	private Context context;
	
	
	public FileService(Context context) {
		this.context = context;
	}


	/**
	 * 以私有模式输出文件内容
	 * @param fileName
	 * @param content
	 * @throws Exception
	 */
	public void save(String fileName, String content) throws Exception {
		FileOutputStream outStream = context.openFileOutput(fileName, Context.MODE_PRIVATE);
		outStream.write(content.getBytes());
		outStream.close();
	}
}

3>再写控制层之前，先用JUnit进行测试。

package com.duantl.file;

import android.test.AndroidTestCase;

import com.duantl.service.FileService;

public class FileServiceTest extends AndroidTestCase {

	public void saveTest() throws Exception {
		FileService fileService = new FileService(this.getContext());
		fileService.save("www.txt", "wangguan");
	}
}

当然别忘记了改AndroidManifest.xml，添加JUnit配置

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.duantl"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="8" />

    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <uses-library android:name="android.test.runner" />
        <activity android:name="file.MainActivity"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
    <instrumentation android:name="android.test.InstrumentationTestRunner"
  			android:targetPackage="com.duantl" android:label="Tests for My App" />
</manifest>

4>测试成功，那么好，就开始控制层。

package com.duantl.file;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

import com.duantl.service.FileService;

public class MainActivity extends Activity {
    /** Called when the activity is first created. */
	private EditText fileNameEdit = null;
	private EditText fileTxtEdit = null;
	private Button fileSaveBtn = null;
	private FileService fileService;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        fileNameEdit = (EditText)this.findViewById(R.id.fileNameEdit);
        fileTxtEdit = (EditText)this.findViewById(R.id.fileTxtEdit);
        fileSaveBtn = (Button)this.findViewById(R.id.fileSaveBtn);
        
        fileSaveBtn.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View arg0) {
				// TODO Auto-generated method stub
				String fileNameStr = fileNameEdit.getText().toString();
				String fileTxtStr = fileTxtEdit.getText().toString();
				
				fileService = new FileService(MainActivity.this);
				try {
					fileService.save(fileNameStr, fileTxtStr);
					Toast.makeText(MainActivity.this, R.string.success, Toast.LENGTH_LONG).show();
				} catch (Exception e) {
					// TODO Auto-generated catch block
					Toast.makeText(MainActivity.this, R.string.error, Toast.LENGTH_LONG).show();
					e.printStackTrace();
				}
			}
		});
    }
}

写功能就写好了，，那么看看读取的功能。。。