文件存储简单代码

下面给大家提供一些简单的代码，运行结果和代码如下

acyity_main.xml<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    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.bz0209.filedemo.MainActivity">    <Button        android:text="Ok"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@+id/etInfo"        android:layout_centerHorizontal="true"        android:layout_marginTop="32dp"        android:onClick="saveDate"        android:id="@+id/btnOk" />    <EditText        android:drawableLeft="@mipmap/ic_launcher"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:inputType="textPersonName"        android:hint="input infos"        android:ems="10"        android:layout_marginTop="154dp"        android:id="@+id/etInfo"        android:layout_alignParentTop="true"        android:layout_centerHorizontal="true" /></RelativeLayout>FileService.javapackage com.example.bz0209.filedemo.model;import android.content.Context;import java.io.BufferedWriter;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import java.io.OutputStreamWriter;/** * Created by Administrator on 2017/3/31. */public class FileService {    private Context context;    public FileService(Context context){        this.context=context;    }    public boolean save(String content){        FileOutputStream fos=null;        OutputStreamWriter osw=null;        BufferedWriter bw=null;        try{             fos=context.openFileOutput("data",Context.MODE_PRIVATE);             osw=new OutputStreamWriter(fos);             bw=new BufferedWriter(osw);            bw.write(content);            return true;    }catch (FileNotFoundException er){        er.printStackTrace();    }catch (IOException e){            e.printStackTrace();        }finally {            try {                if (bw != null)                    bw.close();                if (osw!=null)                    osw.close();                if (fos!=null)                    fos.close();            }catch(IOException e){                e.printStackTrace();            }        }        return false;        }}ExampleInstrumentedTest.javapackage com.example.bz0209.filedemo;import android.content.Context;import android.support.test.InstrumentationRegistry;import android.support.test.runner.AndroidJUnit4;import com.example.bz0209.filedemo.model.FileService;import org.junit.Test;import org.junit.runner.RunWith;import static org.junit.Assert.*;/** * Instrumentation test, which will execute on an Android device. * * @see <a href="http://d.android.com/tools/testing">Testing documentation</a> */@RunWith(AndroidJUnit4.class)public class ExampleInstrumentedTest {    @Test    public void useAppContext() throws Exception {        // Context of the app under test.        Context appContext = InstrumentationRegistry.getTargetContext();        assertEquals("com.example.bz0209.filedemo", appContext.getPackageName());    }    public void save(){        Context appContext=InstrumentationRegistry.getTargetContext();        FileService fileService=new FileService(appContext);        assertEquals(true,fileService.save("hello test"));    }}MainActicity.javapackage com.example.bz0209.filedemo;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;import android.widget.EditText;import com.example.bz0209.filedemo.model.FileService;public class MainActivity extends AppCompatActivity {   private EditText etIofo;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        etIofo=(EditText) findViewById(R.id.etInfo);    }    public void saveDate(View view){        FileService fileService=new FileService(this);        fileService.save(etIofo.getText().toString());    }}