Java 作为文本文件保存到 SD 卡
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Saving to SD card as text file
提问by user2967906
stopWriting = (Button) findViewById(R.id.save);
stopWriting.setOnClickListener(new OnClickListener() {
@SuppressLint("SdCardPath")
public void onClick(View v) {
// stop recording the sensor data
try {
myFile = new File("/sdcard/SensorData/" + txtData.getText() + ".txt");
myFile.createNewFile();
sData = new FileOutputStream(myFile);
myOutWriter = new OutputStreamWriter(sData);
myBufferedWriter = new BufferedWriter(myOutWriter);
myPrintWriter = new PrintWriter(myBufferedWriter);
//if(myFile != null )//stopFlag = mSensorManager.cancelTriggerSensor(null, null);
Toast.makeText(getBaseContext(), "Done", Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
}
}
});
I am trying to save gyroscope data to txt file but it does not save. If anybody finds the problem, please help to me correct it.
我正在尝试将陀螺仪数据保存到 txt 文件，但它没有保存。如果有人发现问题，请帮助我纠正它。
回答by Gil Moshayof
Try this code:
试试这个代码：
public void writeToFile(String fileName, String body)
{
FileOutputStream fos = null;
try {
final File dir = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/folderName/" );
if (!dir.exists())
{
if(!dir.mkdirs()){
Log.e("ALERT","could not create the directories");
}
}
final File myFile = new File(dir, fileName + ".txt");
if (!myFile.exists())
{
myFile.createNewFile();
}
fos = new FileOutputStream(myFile);
fos.write(body.getBytes());
fos.close();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Also, remember to include the external storage permission in your manifest file:
另外，请记住在清单文件中包含外部存储权限：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
and on android 6.0 to ask for permission for WRITE_EXTERNAL_STORAGE
并在 android 6.0 上请求 WRITE_EXTERNAL_STORAGE 的许可
回答by Gabi Moreno
Have you used permission to write in sd?
您是否使用过在 sd 中写入的权限？
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
回答by Rohit5k2
I am doing it like this
我这样做
public void write()
{
FileOutputStream output = null;
try
{
String mediaState = Environment.getExternalStorageState();
if(mediaState.equalsIgnoreCase(Environment.MEDIA_MOUNTED))
{
output = new FileOutputStream(new File(Environment.getExternalStorageDirectory() + "/download/shared.txt"));
String str = "Hello, writing to a text file";
byte[] b = encrypt2(str);
output.write(b);
}
else
{
// error
}
}
catch (IOException e)
{
e.printStackTrace();
}
finally
{
try
{
if (output != null)
output.close();
}
catch (IOException e)
{
e.printStackTrace();
}
}
}
public static byte[] encrypt2(String value)
{
byte[] input = value.getBytes();
int nLen = input.length;
if(nLen % 2 != 0)
{
nLen--;
}
byte temp;
for (int i = 0; i < nLen; i += 2)
{
temp = input[i+1];
input[i+1] = input[i];
input[i] = temp;
}
// do encryption
return Base64.encode(input, Base64.NO_WRAP);
}
Also this permission is required
也需要此权限
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
回答by Hariharan
Try this..
尝试这个..
stopWriting.setOnClickListener(new OnClickListener() {
@SuppressLint("SdCardPath")
public void onClick(View v) {
// stop recording the sensor data
try {
myFile = new File("/sdcard/SensorData/" + txtData.getText() + ".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 SD " + txtData.getText() + ".txt",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
}
});
and also external storage permission in your manifest file:
以及清单文件中的外部存储权限：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
回答by Jitesh Dalsaniya
try this code its working for me.
试试这个代码对我有用。
try {
File myFile = new File("/sdcard/mysdfile.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 SD 'mysdfile.txt'",
Toast.LENGTH_SHORT).show();
} catch (Exception e) {
Toast.makeText(getBaseContext(), e.getMessage(),
Toast.LENGTH_SHORT).show();
}
dont forget to take permission
不要忘记获得许可
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
回答by Dhiraj Choudhary
First Declare this permission to your androidManifest.xml:
首先向您的 androidManifest.xml 声明此权限：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Then write this code on your button click events
然后在您的按钮单击事件上编写此代码
try {
putStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter =new OutputStreamWriter(fOut);
myOutWrite File myFile = new File("/sdcard/SensorData.txt");
myFile.createNewFile();
FileOutr.append(txtData.getText());
myOutWriter.close();
fOut.close();
Toast.makeText(v.getContext(),"Done writing SD 'SensorData.txt'", Toast.LENGTH_SHORT).show();
txtData.setText("");
}
catch (Exception e)
{
Toast.makeText(v.getContext(), e.getMessage(),Toast.LENGTH_SHORT).show();
}
}
