Question

我一直在开发一个关于HTC愿望的应用程序。它运行正常。单击按钮时的应用程序从我的Web服务器下载文件并将其保存到SD卡上。

我现在想在Samsung Galaxy Tab上运行此应用程序。但是，当我点击按钮时会崩溃。

我能看到的唯一原因是该标签不允许访问SD卡。它与HTC Deisre手机中的SD卡相同，不受写保护或其他任何东西？

任何人都知道什么是错的？

这是我用来下载文件并将其存储在卡上的代码......

 class CreatefilesTask extends AsyncTask<Object, Integer, Boolean> {
    protected Boolean doInBackground(Object... arg0) {
        try{
            URL url  = new URL("http://213.143.36.32/file.csv");
            URLConnection conexion = url.openConnection();
            conexion.connect();
            int lenghtOfFile = conexion.getContentLength();
            InputStream is = url.openStream();
            File testDirectory = 
            new File(Environment.getExternalStorageDirectory()+"/File");
            if(!testDirectory.exists()){
                testDirectory.mkdir();
            }
            FileOutputStream fos = new FileOutputStream(testDirectory+"/file.csv");
            byte data[] = new byte[1024];
            int count = 0;
            long total = 0;
            int progress = 0;
            while ((count=is.read(data)) != -1){
                total += count;
                int progress_temp = (int)total*100/lenghtOfFile;
                if(progress_temp%10 == 0 && progress != progress_temp){
                    progress = progress_temp;
                }
                fos.write(data, 0, count);
            }
            is.close();
            fos.close();
        }
        catch(Exception e){
            e.printStackTrace();
        }

这在Desire上运作良好。

栈跟踪..

03-31 12:45:07.823: INFO/PowerManagerService(2494): Ulight 3->7|0
03-31 12:45:07.831: VERBOSE/WindowManager(2494): Delivering toWindow{48419208 com.android.qservices/com.android.qservices.AdminActivity paused=false}
03-31 12:45:07.898: VERBOSE/WindowManager(2494): Delivering toWindow{48419208 com.android.qservices/com.android.qservices.AdminActivity paused=false}
03-31 12:45:08.261: WARN/System.err(5314): java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
03-31 12:45:08.261: WARN/System.err(5314):     at android.os.Handler.<init>(Handler.java:121)
03-31 12:45:08.265: WARN/System.err(5314):     at android.widget.Toast.<init>(Toast.java:77)
03-31 12:45:08.265: WARN/System.err(5314):     at android.widget.Toast.makeText(Toast.java:266)
03-31 12:45:08.269: WARN/System.err(5314):     at com.android.qservices.AdminActivity$CreatefilesTask.doInBackground(AdminActivity.java:117)
03-31 12:45:08.269: WARN/System.err(5314):     at com.android.qservices.AdminActivity$CreatefilesTask.doInBackground(AdminActivity.java:1)
03-31 12:45:08.269: WARN/System.err(5314):     at android.os.AsyncTask$2.call(AsyncTask.java:185)
03-31 12:45:08.269: WARN/System.err(5314):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
03-31 12:45:08.273: WARN/System.err(5314):     at java.util.concurrent.FutureTask.run(FutureTask.java:137)
03-31 12:45:08.273: WARN/System.err(5314):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
03-31 12:45:08.273: WARN/System.err(5314):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
03-31 12:45:08.273: WARN/System.err(5314):     at java.lang.Thread.run(Thread.java:1096)
03-31 12:45:08.280: WARN/System.err(5314): java.io.FileNotFoundException: /mnt/sdcard/File/file.csv (No such file or directory)
03-31 12:45:08.284: WARN/System.err(5314):     at org.apache.harmony.luni.platform.OSFileSystem.openImpl(Native Method)
03-31 12:45:08.284: WARN/System.err(5314):     at org.apache.harmony.luni.platform.OSFileSystem.open(OSFileSystem.java:152)
03-31 12:45:08.288: WARN/System.err(5314):     at java.io.FileInputStream.<init>(FileInputStream.java:82)
03-31 12:45:08.288: WARN/System.err(5314):     at com.android.qservices.AdminActivity$CreatefilesTask.doInBackground(AdminActivity.java:148)
03-31 12:45:08.288: WARN/System.err(5314):     at com.android.qservices.AdminActivity$CreatefilesTask.doInBackground(AdminActivity.java:1)
03-31 12:45:08.288: WARN/System.err(5314):     at android.os.AsyncTask$2.call(AsyncTask.java:185)
03-31 12:45:08.292: WARN/System.err(5314):     at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
03-31 12:45:08.292: WARN/System.err(5314):     at java.util.concurrent.FutureTask.run(FutureTask.java:137)
03-31 12:45:08.292: WARN/System.err(5314):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1068)
03-31 12:45:08.296: WARN/System.err(5314):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:561)
03-31 12:45:08.296: WARN/System.err(5314):     at java.lang.Thread.run(Thread.java:1096)

Answer 1

三星Galaxy Tab拥有大量内部闪存。因此Environment.getExternalStorageDirectory()会返回/mnt/sdcard/，但这实际上是内部存储空间。真正的外部存储位于/mnt/sdcard/external_sd/。有关详细信息，请参阅this post。

Answer 2

找到答案！在Galaxy选项卡上，存储不仅是/ sdcard，而是/ sdcard / external_sd /

Answer 3

我想这条线会造成麻烦：

new FileOutputStream(testDirectory+"/file.csv");

首先创建目录file，但根据您的堆栈跟踪，您尝试访问SD卡根目录上的file.csv。所以我想你不能简单地将file.csv附加到testDirectory类型的File变量。

将应用程序转移到三星Galaxy Tab问题

3 个答案: