使用內部存儲(Internal Storage)

可以直接在設備上的內部存儲(Internal Storage)保存文件. 默認情況下, 文件保存到內部存儲是應用程式私有的, 其他應用程序(用戶)無法訪問. 當用戶卸載應用程序, 這些文件也會被刪除.

範例:



main.xml

<?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:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="@string/hello"
  />
<EditText
  android:id="@+id/input"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
<Button
  android:id="@+id/write"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="Write"
  />
<Button
  android:id="@+id/read"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="Read"
  />
<TextView
  android:id="@+id/output"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
</LinearLayout>

主代碼, AndroidInternalStorage.java

package com.AndroidInternalStorage;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

public class AndroidInternalStorage extends Activity {

String FILENAME = "MyFile";

EditText edittextInput;
TextView textviewOutput;

  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
      edittextInput = (EditText)findViewById(R.id.input);
      Button buttonWrite = (Button)findViewById(R.id.write);
      Button buttonRead = (Button)findViewById(R.id.read);
      textviewOutput = (TextView)findViewById(R.id.output);
    
      buttonWrite.setOnClickListener(buttonWriteOnClickListener);
      buttonRead.setOnClickListener(buttonReadOnClickListener);
  }

  private Button.OnClickListener buttonWriteOnClickListener
  = new Button.OnClickListener(){

 @Override
 public void onClick(View v) {
  // TODO Auto-generated method stub
 
  String string = edittextInput.getText().toString();
 
  FileOutputStream fos;
  try {
   fos = openFileOutput(FILENAME, Context.MODE_PRIVATE);
   fos.write(string.getBytes());
   fos.close();
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 
 
 }};

  private Button.OnClickListener buttonReadOnClickListener
  = new Button.OnClickListener(){

 @Override
 public void onClick(View v) {
  // TODO Auto-generated method stub
 
  FileInputStream fis;
  try {
   fis = openFileInput(FILENAME);
   byte[] input = new byte[fis.available()];
   while (fis.read(input) != -1) {}
   textviewOutput.setText(new String(input));
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 
 
 
 }};
}