Android Question CursorIndex Out Of Bounds Exception

[Alexander Stolte]

Hello great community!,

I have errors by sending video files over WLAN.

Error Function:

Sub GetPathFromContentResult(UriString As String) As String
  If UriString.StartsWith("/") Then Return UriString 'If the user used a file manager to choose the image
  Dim Cursor1 As Cursor
  Dim Uri1 As Uri
  Dim Proj() As String = Array As String("_data")
  Dim cr As ContentResolver
  cr.Initialize("")
  If UriString.StartsWith("content://com.android.providers.media.documents") Then
  Dim i As Int = UriString.IndexOf("%3A")
  Dim id As String = UriString.SubString(i + 3)
  Uri1.Parse("content://media/external/images/media")
  Cursor1 = cr.Query(Uri1, Proj, "_id = ?", Array As String(id), "")
  Else
  Uri1.Parse(UriString)
  Cursor1 = cr.Query(Uri1, Proj, "", Null, "")
  End If
  Cursor1.Position = 0
  Dim res As String
  res = Cursor1.GetString("_data")
  Cursor1.Close
  Return res
End Sub

Yes i Know "GetPathFromContentResult" is not the best.

and here is the error line:

 res = Cursor1.GetString("_data")

And the last but not the least, the full error log:

Installing file.
PackageAdded: package:b4a.WireSharing
** Activity (main) Create, isFirst = true **
** Activity (main) Resume **
** Service (wiresharing) Create **
** Service (wiresharing) Start **
** Activity (main) Pause, UserClosed = false **
** Activity (main) Resume **
StartAStream
** Activity (main) Pause, UserClosed = false **
sending message to waiting queue (OnActivityResult)
running waiting messages (1)
main_getpathfromcontentresult (B4A line: 277)
res = Cursor1.GetString("_data")
android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0
    at android.database.AbstractCursor.checkPosition(AbstractCursor.java:460)
    at android.database.AbstractWindowedCursor.checkPosition(AbstractWindowedCursor.java:136)
    at android.database.AbstractWindowedCursor.getString(AbstractWindowedCursor.java:50)
    at android.database.CursorWrapper.getString(CursorWrapper.java:137)
    at anywheresoftware.b4a.sql.SQL$CursorWrapper.GetString(SQL.java:355)
    at b4a.WireSharing.main._getpathfromcontentresult(main.java:927)
    at b4a.WireSharing.main._cc_result(main.java:812)
    at java.lang.reflect.Method.invoke(Native Method)
    at anywheresoftware.b4a.BA.raiseEvent2(BA.java:169)
    at anywheresoftware.b4a.BA.raiseEvent(BA.java:153)
    at anywheresoftware.b4a.phone.Phone$ContentChooser$1.ResultArrived(Phone.java:843)
    at anywheresoftware.b4a.BA$4.run(BA.java:513)
    at anywheresoftware.b4a.BA.setActivityPaused(BA.java:398)
    at b4a.WireSharing.main$ResumeMessage.run(main.java:300)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:158)
    at android.app.ActivityThread.main(ActivityThread.java:7229)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)

Thanks for helping me

greetings.

 

[Alexander Stolte]

i see:

Uri1.Parse("content://media/external/images/media")

"/images"

Means that only pictures can be sent?
Sry I unfortunately only afterwards seen :/

 

[DonManfred]

Means that only pictures can be sent?

you do not send anything. you are requesting results from the conentresolver.

I guess content://media/external/video is the way to go to get a list of videos

 

[Alexander Stolte]

@DonManfred

how is that by other files like .txt or .pdf?
Or is there a way to combine that? So you have a path and you can receive videos, pictures and other files?
So I do not have to write a thousand functions for the individual types

 

[DonManfred]

Androids Gallery does not provide indexes for txt pdf or other files other than PICTURES and VIDEOS

What exactly you want archieve?

Edit: You can surely list all files of all folders of your internal or external sdcard (or even search for *.txt) using my Wildcard-class

 

[Alexander Stolte]

@DonManfred

I orient myself on this tutorial: https://www.b4x.com/android/forum/t...nd-and-receive-files-with-asyncstreams.30493/

"AsyncStreams can be used to send and receive files of any size"

 

[DonManfred]

I orient myself on this tutorial

Ok, but this thread has nothing to do with asyncstreams!

 

[Alexander Stolte]

@DonManfred

But in the title is:
"FileTransfer - Send and receive files with AsyncStreams"

why do you think that?

 

[DonManfred]

But in the title is

CursorIndex Out Of Bounds Exception

 

[Alexander Stolte]

The error message tells me nothing, so I asked here for advice

Or I have misunderstood which thread you mean.

 

[DonManfred]

I maybe did not declrared exactly enough....

Ok, but this thread has nothing to do with asyncstreams!

I was not talking about the asyncstream-thread. I was talking about THIS thread here.

 

[Alexander Stolte]

yes, but the code is from the other Thread :/

And because I before with the standard function only errors gotten, I've found a more recent code for the function which just makes me problems.

https://www.b4x.com/android/forum/threads/using-photos-from-the-phone.37444/#post-221367

 

[DonManfred]

But you read the comment in the thread, yes?

You can use this code to get the full path (if such is available)

The interesting part is inside brackets. the path is NOT always available.

 

[Alexander Stolte]

My english is not the best and there may be times already to misunderstandings. Sry

But when I click in the FileBrowser and get the file, but there must be a path, otherwise the browser would not display this file or?

 

[Erel]

GetPathFromContentResult is problematic and is not guaranteed to work.

You don't need to use it if you want to read data from the resource. You can open an InputStream with the parameters passed in the Result sub.
You will not be able to use it with AsyncStreams.WriteStream but you will be able to read data from the InputStream and write it to AsyncStreams with AsyncStreams.Write.

 

[Alexander Stolte]

@Erel

I have thought about everything again.

So the user is clicked on a button, a file-manager opens. The user choose a Picture, video or other files...
Then the manager closes and in a label comes the absolute path to the file.

How can i do this with b4a?

I have read to all the topics, but I absolutely want to do it with an installed manager.

greetings

 

[Erel]

It is not always possible to get the path. The good thing is that you don't need the absolute path.

 

[Alexander Stolte]

@Erel

And how can I start such a manager under android? In visual studio I have an open file dialog for this. Is there a library or tutorial for this?

 

[Erel]

@Erel

Please don't limit your questions to a single member. This is a public forum.

You should use Content Chooser.

 

[Alexander Stolte]

thanks, sry my misstake. Nevertheless thank you