我正在创建一个小应用程序,让用户阅读/ data / local中某个文本文件中的内容,编辑它,然后保存它。 我已经通过在这里和那里使用一些教程来完成所有工作,但仍然有一些不起作用。
已经实现了Root访问,并且写入/读取文件也已完成,但是当按下“Write”按钮时,我得到一个祝酒词“open failed:EACCES(Permission denied)”。不幸的是,谷歌在这方面没有多大帮助。 另外,我使用WRITE_TO_EXTERNAL_STORAGE权限。
代码:
package bas.sie.datadatafix;
import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.actionbarsherlock.app.SherlockActivity;
public class DataFixActivity extends SherlockActivity {
EditText txtData;
Button btnReadSDFile;
Button btnWriteSDFile;
Button btnReadSkipFile;
Button btnWriteSkipFile;
Button btnClearScreen;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Process p;
try {
// Preform su to get root privledges
p = Runtime.getRuntime().exec("su");
// Attempt to write a file to a root-only
DataOutputStream os = new DataOutputStream(p.getOutputStream());
os.writeBytes("echo \"Do I have root?\" >/system/sd/temporary.txt\n");
// Close the terminal
os.writeBytes("exit\n");
os.flush();
try {
p.waitFor();
if (p.exitValue() != 255) {
// TODO Code to run on success
Toast.makeText(this, "root", Toast.LENGTH_LONG);
}
else {
// TODO Code to run on unsuccessful
Toast.makeText(this, "No root", Toast.LENGTH_LONG);
}
} catch (InterruptedException e) {
// TODO Code to run in interrupted exception
Toast.makeText(this, "No root", Toast.LENGTH_LONG);
}
} catch (IOException e) {
// TODO Code to run in input/output exception
Toast.makeText(this, "NO root", Toast.LENGTH_LONG);
}
if(!Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())){
Toast.makeText(this, "External SD card not mounted", Toast.LENGTH_LONG).show();
}
txtData = (EditText) findViewById(R.id.txtData);
btnReadSDFile = (Button) findViewById(R.id.btnReadSDFile);
btnReadSDFile.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// write on SD card file data in the text box
try {
File myFile = new File("/data/local/move_cache.txt");
FileInputStream fIn = new FileInputStream(myFile);
BufferedReader myReader = new BufferedReader(
new InputStreamReader(fIn));
String aDataRow = "";
String aBuffer = "";
while ((aDataRow = myReader.readLine()) != null) {
aBuffer += aDataRow + "\n";
}
txtData.setText(aBuffer);
myReader.close();
Toast.makeText(getBaseContext(),
"Done reading from SD: 'move_cache.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}
});
btnWriteSDFile = (Button) findViewById(R.id.btnWriteSDFile);
btnWriteSDFile.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// write on SD card file data in the text box
try {
File myFile = new File("/data/local/move_cache.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter = new OutputStreamWriter(
fOut);
myOutWriter.append(txtData.getText());
myOutWriter.close();
fOut.close();
Toast.makeText(getBaseContext(),
"Done writing to SD: 'move_cache.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}
});
btnReadSkipFile = (Button) findViewById(R.id.btnReadSkipFile);
btnReadSkipFile.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// write on SD card file data in the text box
try {
File myFile = new File("/data/local/skip_apps.txt");
FileInputStream fIn = new FileInputStream(myFile);
BufferedReader myReader = new BufferedReader(
new InputStreamReader(fIn));
String aDataRow = "";
String aBuffer = "";
while ((aDataRow = myReader.readLine()) != null) {
aBuffer += aDataRow + "\n";
}
txtData.setText(aBuffer);
myReader.close();
Toast.makeText(getBaseContext(),
"Done reading from SD: 'skip_apps.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}
});
btnWriteSkipFile = (Button) findViewById(R.id.btnWriteSkipFile);
btnWriteSkipFile.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// write on SD card file data in the text box
try {
File myFile = new File("/data/local/skip_apps.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter = new OutputStreamWriter(
fOut);
myOutWriter.append(txtData.getText());
myOutWriter.close();
fOut.close();
Toast.makeText(getBaseContext(),
"Done writing to SD: 'skip_apps.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}
});
btnClearScreen = (Button) findViewById(R.id.btnClearScreen);
btnClearScreen.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// clear text box
txtData.setText("");
}
});
}// onCreate
}
提前致谢,
Bas
答案 0 :(得分:1)
尝试使用这个逻辑来编写和读取本地存储上的文件,只剩下一个,尽管我知道你做了,但仍然......使用WRITE_TO_EXTERNAL_STORAGE权限。
从文件中读取
File f = new File("my.txt");
FileReader fr = new FileReader(f);
BufferedReader br = new BufferedReader(fr);
String s = null;
while ((br=readLine())!=null) {
// Do whatever u want to do with the content of the file,eg print it on console using SysOut...etc
}
br.close();
写入文件:
Boolean isDone = true;
Scanner scan = new Scanner(System.in);
File f = new File("my.txt");
FileWriter fr = new FileWriter(f);
BufferedWriter br = new BufferedWriter(fr);
while (b) {
if (!b) {
br.write(new Scanner(System.in).nextLine());
}
}