Java 如何在内存中的csv文件中创建并保存传感器数据
我试图在内部存储器的文件中获取加速计数据,我尝试了许多方法,但我得到了一些错误,如java.io.FileNotFoundException:Value.csv:open failed:EROFS(只读文件系统)或ESIDIRJava 如何在内存中的csv文件中创建并保存传感器数据,java,android,Java,Android,我试图在内部存储器的文件中获取加速计数据,我尝试了许多方法,但我得到了一些错误,如java.io.FileNotFoundException:Value.csv:open failed:EROFS(只读文件系统)或ESIDIR @RequiresApi(api = Build.VERSION_CODES.N) public class MainActivity extends Activity implements SensorEventListener,View.OnClickListener
@RequiresApi(api = Build.VERSION_CODES.N)
public class MainActivity extends Activity implements SensorEventListener,View.OnClickListener {
private TextView xText, yText, zText;
private Sensor sensor;
private SensorManager sManager;
private Button startB, stopB;
private boolean mInitialized;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Create sensor manager
sManager = (SensorManager) getSystemService(SENSOR_SERVICE);
// Accelerometer sensor
sensor = sManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
//Register sensor Listener
sManager.registerListener(this, sensor, SensorManager.SENSOR_DELAY_NORMAL);
// assign Textview
xText = (TextView) findViewById(R.id.xText);
Button startButton = (Button) findViewById(R.id.startB);
Button stopButton = (Button) findViewById(R.id.stopB);
startButton.setOnClickListener(this);
stopButton.setOnClickListener(this);
mInitialized = false;
}
public void onResume() {
super.onResume();
sManager.registerListener(this, sensor, SensorManager.SENSOR_DELAY_NORMAL);
}
protected void onPause() {
super.onPause();
sManager.unregisterListener(this);
}
public void onAccuracyChanged(Sensor sensor, int acc) {
}
public void onSensorChanged(SensorEvent event) {
xText.setText(" X :" + Float.toString(event.values[0]) + "\n" +
" Y :" + Float.toString(event.values[1]) + "\n" +
" Z :" + Float.toString(event.values[2]));
try {
writeToCsv(Float.toString(event.values[0]), Float.toString(event.values[1]), Float.toString(event.values[2]));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void onClick(View v) {
switch (v.getId()) {
case R.id.startB:
sManager.registerListener(this, sensor, SensorManager.SENSOR_DELAY_NORMAL);
break;
case R.id.stopB:
sManager.unregisterListener(this);
break;
}
}
public void writeToCsv(String x, String y, String z) throws IOException {
Calendar c = Calendar.getInstance();
File path = Environment.getDataDirectory();
boolean success = true;
if (!path.exists()) {
success = path.mkdir();
}
if (success) {
String csv = "Value.csv";
FileWriter file_writer = new FileWriter(csv, true);
String s = c.get(Calendar.HOUR) + "," + c.get(Calendar.MINUTE) + "," + c.get(Calendar.SECOND) + "," + c.get(Calendar.MILLISECOND) + "," + x + "," + y + "," + z + "\n";
file_writer.append(s);
file_writer.close();
}
}
}
将传递路径/数据。正如您所看到的,它既不可读也不可写。例如,改为
File path = getFilesDir();
抱歉,首先,是否要尝试在文件编写器中使用该
path
变量?否则,你为什么要费心制作文件夹呢?是的,我很想,但我不明白怎么做,每次我通过尝试教程中看到的东西来更改代码时,都会出现错误,所以我查看了如何修复,但它不起作用。
File path = getFilesDir();