Question

此函数创建一个文件，但我无法弄清楚文件创建的位置，以及是否有人有解决方案从外部存储创建特定目录中的文件非常受欢迎:)非常感谢

private void writeFileToInternalStorage() {
    String eol = System.getProperty("line.separator");
    BufferedWriter writer = null;
    try {
      writer = new BufferedWriter(new OutputStreamWriter(openFileOutput("myfile", MODE_WORLD_WRITEABLE)));
      writer.write("This is a test1." + eol);
      writer.write("This is a test2." + eol);
    } catch (Exception e) {
            e.printStackTrace();
    } finally {
      if (writer != null) {
        try {
            writer.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
      }
    }
}

Answer 1

openFileOutput始终在本地项目目录中创建文件，即与getFilesDir()

返回的文件相同

您的文件将在/data/data/your.package.name/

创建

要写入extrnal存储，您需要执行以下操作。

File sdCard = Environment.getExternalStorageDirectory();
File dir = new File (sdcard.getAbsolutePath() + "/MyDir");
dir.mkdirs();
File file = new File(dir, "filename");

FileOutputStream f = new FileOutputStream(file);
...

最后不要忘记包括

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

在清单中。

Answer 2

将在内部文件夹上创建：/data/data/com.package.name/您无法使用文件浏览器访问该文件夹。

如果您想轻松访问该文件，可以尝试在SD卡上创建它：

/*...*/
String baseDir = Environment.getExternalStorageDirectory().getAbsolutePath();
String fileName = baseDir + "/"+ "myFile.txt";
FileOutputStream writer = null;
try {
    writer = new FileOutputStream(fileName);
    writer.write("This is a test1." + eol);
    /*...*/

Answer 3

查询

将在何处创建文件

它会在内部存储中创建，因为函数名称就是这样的 / data / data / yourApp_package_as_in_manifest /（可以在DDMS中看到）

查询

如果有人有解决方案在特定目录中创建文件来自外部存储非常欢迎

根据链接Write a file in external storage in Android .........

** Method to check whether external media available and writable. This is adapted from
       http://developer.android.com/guide/topics/data/data-storage.html#filesExternal */

     private void checkExternalMedia(){
          boolean mExternalStorageAvailable = false;
        boolean mExternalStorageWriteable = false;
        String state = Environment.getExternalStorageState();

        if (Environment.MEDIA_MOUNTED.equals(state)) {
            // Can read and write the media
            mExternalStorageAvailable = mExternalStorageWriteable = true;
        } else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
            // Can only read the media
            mExternalStorageAvailable = true;
            mExternalStorageWriteable = false;
        } else {
            // Can't read or write
            mExternalStorageAvailable = mExternalStorageWriteable = false;
        }   
        tv.append("\n\nExternal Media: readable="
                +mExternalStorageAvailable+" writable="+mExternalStorageWriteable);
    }

    /** Method to write ascii text characters to file on SD card. Note that you must add a 
       WRITE_EXTERNAL_STORAGE permission to the manifest file or this method will throw
       a FileNotFound Exception because you won't have write permission. */

    private void writeToSDFile(){

        // Find the root of the external storage.
        // See http://developer.android.com/guide/topics/data/data-  storage.html#filesExternal

        File root = android.os.Environment.getExternalStorageDirectory(); 
        tv.append("\nExternal file system root: "+root);

        // See https://stackoverflow.com/questions/3551821/android-write-to-sd-card-folder

        File dir = new File (root.getAbsolutePath() + "/download");
        dir.mkdirs();
        File file = new File(dir, "myData.txt");

        try {
            FileOutputStream f = new FileOutputStream(file);
            PrintWriter pw = new PrintWriter(f);
            pw.println("Hi , How are you");
            pw.println("Hello");
            pw.flush();
            pw.close();
            f.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            Log.i(TAG, "******* File not found. Did you" +
                    " add a WRITE_EXTERNAL_STORAGE permission to the   manifest?");
        } catch (IOException e) {
            e.printStackTrace();
        }   
        tv.append("\n\nFile written to "+file);
    }

并为清单

添加WRITE_EXTERNAL_STORAGE权限

如果我这样做的话，在android中创建的文件将在哪里

3 个答案: