package com.example.exercise_file2;import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.io.RandomAccessFile;import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;public class MainActivity extends Activity {
private Button bnWrite;
private Button bnRead;
private EditText editWrite;
private EditText editRead;
final String FILE_NAME="MyFile"; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bnWrite=(Button)findViewById(R.id.bnWrite);
bnRead=(Button)findViewById(R.id.bnRead);
editWrite=(EditText)findViewById(R.id.editWrite);
editRead=(EditText)findViewById(R.id.editRead);
bnWrite.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO 自动生成的方法存根
write(editWrite.getText().toString());
editWrite.setText("");
}
});
bnRead.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO 自动生成的方法存根
editRead.setText(read());
}
});
}
/*
* 对手机本地文件的读写
*/
/* private String read(){
try {
FileInputStream fis=openFileInput(FILE_NAME);
byte buff[]=new byte[1024];
int hasRead=0;
StringBuilder sb=new StringBuilder("");
while((hasRead=fis.read(buff))>0){ //read(buff[])读入buff.lenght个字节到buff数组
sb.append(new String(buff,0,hasRead));
}
return sb.toString();
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
return null;
}
private void write(String intent)
{
try {
FileOutputStream fos=openFileOutput(FILE_NAME, MODE_APPEND);
PrintStream ps=new PrintStream(fos);
ps.println(intent);
ps.close();
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}*/
private String read(){
if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
File sdCardDir=Environment.getExternalStorageDirectory();
try {
FileInputStream fis=new FileInputStream(sdCardDir.getCanonicalPath()+FILE_NAME);
BufferedReader br=new BufferedReader(new InputStreamReader(fis));
StringBuilder sb=new StringBuilder("");
String line=null;
while((line=br.readLine())!=null){
sb.append(line);
}
return sb.toString();
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
return null;
}
private void write(String content){
if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
File sdCardDir=Environment.getExternalStorageDirectory();
File targetFile=new File(sdCardDir.getAbsolutePath()+FILE_NAME);
try {
RandomAccessFile raf=new RandomAccessFile(targetFile, "wr");
raf.seek(targetFile.length());
raf.write(content.getBytes());
raf.close();
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
这是我的程序,在AndroidManifest.xml中也写了 <uses-permission android:name="android.permission.MOUNT_FORMAT_FILESYSTEMS"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
可是它还是报错Failed to install Exercise_File2.apk on device 'emulator-5556': No such file or directory
[2014-10-15 17:01:33 - Exercise_File2] com.android.ddmlib.SyncException: No such file or directory
[2014-10-15 17:01:33 - Exercise_File2] Launch canceled!
是不是我的SD卡没有运行起来啊???
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.io.RandomAccessFile;import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;public class MainActivity extends Activity {
private Button bnWrite;
private Button bnRead;
private EditText editWrite;
private EditText editRead;
final String FILE_NAME="MyFile"; @Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bnWrite=(Button)findViewById(R.id.bnWrite);
bnRead=(Button)findViewById(R.id.bnRead);
editWrite=(EditText)findViewById(R.id.editWrite);
editRead=(EditText)findViewById(R.id.editRead);
bnWrite.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO 自动生成的方法存根
write(editWrite.getText().toString());
editWrite.setText("");
}
});
bnRead.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO 自动生成的方法存根
editRead.setText(read());
}
});
}
/*
* 对手机本地文件的读写
*/
/* private String read(){
try {
FileInputStream fis=openFileInput(FILE_NAME);
byte buff[]=new byte[1024];
int hasRead=0;
StringBuilder sb=new StringBuilder("");
while((hasRead=fis.read(buff))>0){ //read(buff[])读入buff.lenght个字节到buff数组
sb.append(new String(buff,0,hasRead));
}
return sb.toString();
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
return null;
}
private void write(String intent)
{
try {
FileOutputStream fos=openFileOutput(FILE_NAME, MODE_APPEND);
PrintStream ps=new PrintStream(fos);
ps.println(intent);
ps.close();
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}*/
private String read(){
if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
File sdCardDir=Environment.getExternalStorageDirectory();
try {
FileInputStream fis=new FileInputStream(sdCardDir.getCanonicalPath()+FILE_NAME);
BufferedReader br=new BufferedReader(new InputStreamReader(fis));
StringBuilder sb=new StringBuilder("");
String line=null;
while((line=br.readLine())!=null){
sb.append(line);
}
return sb.toString();
} catch (IOException e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
return null;
}
private void write(String content){
if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
File sdCardDir=Environment.getExternalStorageDirectory();
File targetFile=new File(sdCardDir.getAbsolutePath()+FILE_NAME);
try {
RandomAccessFile raf=new RandomAccessFile(targetFile, "wr");
raf.seek(targetFile.length());
raf.write(content.getBytes());
raf.close();
} catch (Exception e) {
// TODO 自动生成的 catch 块
e.printStackTrace();
}
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
这是我的程序,在AndroidManifest.xml中也写了 <uses-permission android:name="android.permission.MOUNT_FORMAT_FILESYSTEMS"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
可是它还是报错Failed to install Exercise_File2.apk on device 'emulator-5556': No such file or directory
[2014-10-15 17:01:33 - Exercise_File2] com.android.ddmlib.SyncException: No such file or directory
[2014-10-15 17:01:33 - Exercise_File2] Launch canceled!
是不是我的SD卡没有运行起来啊???
解决方案 »
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