package com.example.filemode;

import java.io.FileOutputStream;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

import android.widget.Toast;

public class MainActivity extends Activity implements OnClickListener {

   @Override

   protected void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.activity_main);

      Button btn1 = (Button) findViewById(R.id.btn1);

      Button btn2 = (Button) findViewById(R.id.btn2);

      Button btn3 = (Button) findViewById(R.id.btn3);

      Button btn4 = (Button) findViewById(R.id.btn4);

      // 设置监听事件

      btn1.setOnClickListener(this);

      btn2.setOnClickListener(this);

      btn3.setOnClickListener(this);

      btn4.setOnClickListener(this);

   }

   @Override

   public void onClick(View v) {

      try {

         FileOutputStream fos = null;

         switch (v.getId()) {

            case R.id.btn1:// 私有

                fos = this.openFileOutput("private.txt", MODE_PRIVATE);

                break;

            case R.id.btn2:// 只读

                fos = this.openFileOutput("readable.txt", MODE_WORLD_READABLE);

                break;

            case R.id.btn3:// 只写

                fos = this.openFileOutput("writeable.txt", MODE_WORLD_WRITEABLE);

                break;

            case R.id.btn4:// 可读可写

                fos = this.openFileOutput("public.txt",MODE_WORLD_READABLE + MODE_WORLD_WRITEABLE);

                break;

            default:

                break;

         }

         fos.write("呵呵".getBytes());

         fos.close();

         Toast.makeText(this, "文件保存成功，哈哈。。。", 0).show();

      } catch (Exception e) {

         e.printStackTrace();

         Toast.makeText(this, "文件保存失败楼", 0).show();

      }

   }

}

package com.example.readwrite;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.InputStreamReader;

import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.widget.Toast;

public class MainActivity extends Activity {

   @Override

   protected void onCreate(Bundle savedInstanceState) {

      super.onCreate(savedInstanceState);

      setContentView(R.layout.activity_main);

   }

   public void read(View v){

      try {

         File file = new File("/data/data/com.example.filemode/files/public.txt");

         FileInputStream fis = new FileInputStream(file);

         BufferedReader br = new BufferedReader(new InputStreamReader(fis));

         String text = br.readLine();

         br.close();

         Toast.makeText(this, "哈哈："+text, 0).show();

      } catch (Exception e) {

         e.printStackTrace();

         Toast.makeText(this, "无权读取文件", 0).show();

      }

   }

   public void write(View v){

      File file = new File("/data/data/com.example.filemode/files/public.txt");

      try {

         FileOutputStream fos = new FileOutputStream(file);

         fos.write("LoaderMan".getBytes());

         fos.close();

         Toast.makeText(this, "嘿嘿", 0).show();

      } catch (Exception e) {

         e.printStackTrace();

         Toast.makeText(this, "失败了！", 0).show();

      }

   }

}