java - 在具有正确文件路径和权限的 Android 中找不到文件异常

Question

我正在尝试读取已创建的 CSV 文件。路径变量显示 Android 应用程序文件夹中的正确路径。另外，我已经添加了读写外部存储权限，但我仍然收到文件未找到异常，如 Volley Error toast 消息中所示。

读取 CSV 代码:-

    String path = String.valueOf(this.getExternalFilesDir(null));
    Log.d("Path",path+"/Final.csv");
    File csvFILE = new File(path+"/","Final.csv");
    try {
        CSVReader csvREAD = new CSVReader(new
                FileReader(path));
        String[] csvLINE;
        int skip = 0;
        try {
            Log.d("I was here","kk");
            while((csvLINE = csvREAD.readNext())!=null)
            {
                if(skip > 0)//becasue first line is column headers
                {
                    String PARAM_DISTRICT = csvLINE[0];
                    String PARAM_TALUKA = csvLINE[1];
                    String PARAM_VILLAGE = csvLINE[2];
                    String PARAM_FARMER_NAME = csvLINE[3];
                    String PARAM_CONTACT_NUMBER = csvLINE[4];
                    String PARAM_GAT_NUMBER = csvLINE[5];
                    String PARAM_CROP_NAME = csvLINE[6];
                    String PARAM_LANDUSE = csvLINE[7];
                    String PARAM_SOIL_TYPE = csvLINE[8];
                    int PARAM_SOIL_DEPTH = Integer.parseInt(csvLINE[9]);
                    double PARAM_LATITUDE = Double.parseDouble(csvLINE[10]);
                    double PARAM_LONGITUDE = Double.parseDouble(csvLINE[11]);
                    String PARAM_TIMESTAMP = csvLINE[12];

                    Data STUD_OBJECT = new Data(PARAM_DISTRICT,PARAM_TALUKA,PARAM_VILLAGE,
                            PARAM_FARMER_NAME,PARAM_CONTACT_NUMBER,PARAM_GAT_NUMBER,
                            PARAM_CROP_NAME,PARAM_LANDUSE,PARAM_SOIL_TYPE,PARAM_SOIL_DEPTH,
                            PARAM_LATITUDE,PARAM_LONGITUDE,PARAM_TIMESTAMP
                    );
                    dataArray.add(STUD_OBJECT);
                }
                else
                {
                    skip ++;
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

    } catch (FileNotFoundException e) {
        Toast.makeText(this, "Volley Error", Toast.LENGTH_SHORT).show();
    }

CSV 文件是使用以下代码创建的:

    String Testfile_name="Final";
    Testfile_name=Testfile_name+".csv";
    File logFile = new File(this.getExternalFilesDir(null), Testfile_name);
    if (!logFile.exists())
    {
        try
        {
            logFile.createNewFile();
            String header= "District,Taluka,Village,Farmer_name,Contact_Number,Gat_Number,Crop_name,Landuse,Soil_Type,Soil_Depth,Latitude,Longitude,Timestamp";
            appendLog(header);
        }
        catch (IOException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

Answer 1

这个:

File logFile = new File(this.getExternalFilesDir(null), Testfile_name);

不指向同一个地方:

String path="storage/emulated/0";
Log.d("Path",path+"/Final.csv");
File csvFILE = new File(path+"/","Final.csv");

使它们相同，最好使用代码的第一位和getExternalFilesDir()。