點擊儲存後,建立的檔案儲存在/data/data/<package name>/files
目錄下,可以檢查一下:DDMS——File Explorer——data——data——<package name>——files——file.txt
選中檔案,點擊可以將檔案匯出,便於查看;點擊可將其他檔案添加進來
點擊儲存後,提示框顯示:儲存成功;點擊讀取後,提示框顯示:檔案內容:×××××
布局檔案
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="left" android:text="@string/name" /> <EditText android:id="@+id/name" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="left" android:text="@string/content" /> <EditText android:id="@+id/content" android:layout_width="fill_parent" android:layout_height="wrap_content" android:inputType="textMultiLine" android:minLines="5" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="horizontal" > <Button android:id="@+id/save" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/save" /> <Button android:id="@+id/read" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/read" /> </LinearLayout></LinearLayout>
業務層代碼:
FileService.java
package cn.bzu.fileoperation;import java.io.ByteArrayOutputStream;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import android.content.Context;public class FileService {private Context context;public FileService(Context context) {super();this.context = context;}//儲存資料public void save(String fileName,String content) throws Exception{FileOutputStream fos=context.openFileOutput(fileName, Context.MODE_PRIVATE);fos.write(content.getBytes());fos.close();}//讀取資料public String readFile(String filename) throws IOException{FileInputStream fis=context.openFileInput(filename);int len=0;byte[] buffer=new byte[1024];ByteArrayOutputStream baos=new ByteArrayOutputStream();//往記憶體中輸出資料while((len=fis.read(buffer))!=-1){//如果資料量很大,第2次讀取的資料有可能會把第1次讀取的資料給覆蓋掉baos.write(buffer, 0, len);}byte[] data=baos.toByteArray();//得到記憶體中的資料 以二進位存放的baos.close();fis.close();return new String(data);//根據位元據轉換成所對應的字串}}
MainActivity.java代碼:
package cn.bzu.fileoperation;import java.io.IOException;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.Toast;public class MainActivity extends Activity {private EditText nameText;private EditText contentText;private Button save;private Button read;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);nameText = (EditText) this.findViewById(R.id.name);contentText = (EditText) this.findViewById(R.id.content);save = (Button) this.findViewById(R.id.save);read = (Button) this.findViewById(R.id.read);final FileService fileService = new FileService(this);save.setOnClickListener(new OnClickListener() {public void onClick(View v) {String name = nameText.getText().toString();String content = contentText.getText().toString();try {fileService.save(name, content);} catch (Exception e) {// TODO Auto-generated catch blocke.printStackTrace();}Toast.makeText(MainActivity.this, "儲存成功", Toast.LENGTH_LONG).show();}});read.setOnClickListener(new OnClickListener() {String fileContent;@Overridepublic void onClick(View v) {String name = nameText.getText().toString();try {fileContent = fileService.readFile(name);} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}Toast.makeText(MainActivity.this, "檔案內容:" + fileContent,Toast.LENGTH_LONG).show();}});}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {getMenuInflater().inflate(R.menu.activity_main, menu);return true;}}