相关疑难解决方法(0)

首先,关于这个问题有很多问题,但没有一个反映我的问题.我有例如读这个和这个.

我遇到的问题是,在极少数情况下,我的函数setDestinationInExternalPublicDir导致以下堆栈跟踪:

Fatal Exception: java.lang.RuntimeException: Unable to start receiver com.onlinetvrecorder.otrapp2.listeners.DownloadUpdateReceiver: java.lang.IllegalStateException: Unable to create directory: /mnt/sdcard/Download
       at android.app.ActivityThread.handleReceiver(ActivityThread.java:2274)
       at android.app.ActivityThread.access$1500(ActivityThread.java:131)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1272)
       at android.os.Handler.dispatchMessage(Handler.java:99)
       at android.os.Looper.loop(Looper.java:137)
       at android.app.ActivityThread.main(ActivityThread.java:4791)
       at java.lang.reflect.Method.invokeNative(Method.java)
       at java.lang.reflect.Method.invoke(Method.java:511)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
       at dalvik.system.NativeStart.main(NativeStart.java)
Caused by java.lang.IllegalStateException: Unable to create directory: /mnt/sdcard/Download
       at android.app.DownloadManager$Request.setDestinationInExternalPublicDir(DownloadManager.java:496)
       at com.myapp.Utils.download(SourceFile:752)
       at com.myapp.Receiver.onReceive(SourceFile:20)
       at android.app.ActivityThread.handleReceiver(ActivityThread.java:2267)
       at android.app.ActivityThread.access$1500(ActivityThread.java:131)
       at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1272)
       at android.os.Handler.dispatchMessage(Handler.java:99)
       at android.os.Looper.loop(Looper.java:137)
       at android.app.ActivityThread.main(ActivityThread.java:4791)
       at java.lang.reflect.Method.invokeNative(Method.java)
       at java.lang.reflect.Method.invoke(Method.java:511)
       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) …