无法在我的设备 android 上的 sd 卡上写入

Question

我正在尝试从服务器下载图像并将其保存在 sd 卡上，但失败了

当我在模拟器或其他设备上尝试它时，它工作正常，但我的设备没有。我的设备是galaxy mini gt-s5570

这是我的代码：

public String downloadImage(String imageUrl, String id, String folder) {
        String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/FBLogoQuiz/" + folder + "/";
        Log.d("path", path);
        File FBLogoQuiz = new File(path);
        FBLogoQuiz.mkdirs();
        FBLogoQuiz.mkdir();
        String data = "";
        try {
            URL url = new URL(imageUrl);
            HttpURLConnection connection = (HttpURLConnection) url.openConnection();
            connection.setDoInput(true);
            connection.connect();
            InputStream input = connection.getInputStream();
            Bitmap myBitmap = BitmapFactory.decodeStream(input);

            // create a File object for the parent directory
            File FBLogoQuizDirectory = new File(path, id + ".png");

            // have the object build the directory structure, if needed.
            FBLogoQuizDirectory.createNewFile();
            data = String.valueOf(String.format(path + id + ".png"));

            FileOutputStream stream = new FileOutputStream(data);

            ByteArrayOutputStream outstream = new ByteArrayOutputStream();
            myBitmap.compress(Bitmap.CompressFormat.PNG, 85, outstream);
            byte[] byteArray = outstream.toByteArray();

            stream.write(byteArray);
            stream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

        return data;

    }

Manifest.xml

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

Logcat：

05-24 00:26:10.099: W/System.err(28984): java.io.IOException: No such file or directory
05-24 00:26:10.099: W/System.err(28984):    at java.io.File.createNewFileImpl(Native Method)
05-24 00:26:10.109: W/System.err(28984):    at java.io.File.createNewFile(File.java:1160)
05-24 00:26:10.109: W/System.err(28984):    at com.nileworx.footballlogoquiz.GetUpdatesService.downloadImage(GetUpdatesService.java:229)
05-24 00:26:10.109: W/System.err(28984):    at com.nileworx.footballlogoquiz.GetUpdatesService.getUpdates(GetUpdatesService.java:197)
05-24 00:26:10.109: W/System.err(28984):    at com.nileworx.footballlogoquiz.GetUpdatesService.onHandleIntent(GetUpdatesService.java:127)
05-24 00:26:10.109: W/System.err(28984):    at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:59)
05-24 00:26:10.109: W/System.err(28984):    at android.os.Handler.dispatchMessage(Handler.java:99)
05-24 00:26:10.109: W/System.err(28984):    at android.os.Looper.loop(Looper.java:123)
05-24 00:26:10.109: W/System.err(28984):    at android.os.HandlerThread.run(HandlerThread.java:60)

Answer 1

createNewFile() 在创建文件时不会创建新目录。你需要做的：

FBLogoQuizDirectory().getParentFile().mkdirs();

在创建文件之前。