Android Question Exporting data from B4XTable to .csv file

[TonyVerberne]

I am trying to export records in my table to a .csv file that can then be read into Excel.
I have attached a zip file of the project.

When I press the 'Export' button the app crashes;

Here is the error log report:
Logger connected to: Google Pixel
--------- beginning of main
Copying updated assets files (20)
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
** Activity (main) Resume **
** Activity (main) Pause, UserClosed = false **
Sleep not resumed (context is paused): anywheresoftware.b4a.shell.DebugResumableSub$DelegatableResumableSub
Sleep not resumed (context is paused): anywheresoftware.b4a.shell.DebugResumableSub$DelegatableResumableSub
sending message to waiting queue (activity_permissionresult)
running waiting messages (1)
Permission granted
** Activity (main) Resume **
Index time: 26 ms (96 Items)
Error occurred on line: 158 (EditableTable)
java.io.FileNotFoundException: /data/user/0/b4a.CheeseDiary/files/virtual_assets/table.csv: open failed: ENOENT (No such file or directory)
at libcore.io.IoBridge.open(IoBridge.java:496)
at java.io.FileInputStream.<init>(FileInputStream.java:159)
at anywheresoftware.b4a.objects.streams.File.OpenInput(File.java:204)
at anywheresoftware.b4a.objects.streams.File.Copy(File.java:340)
at b4a.CheeseDiary.editabletable._button1_click(editabletable.java:551)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:732)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:348)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:255)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:144)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:176)
at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:80)
at android.view.View.performClick(View.java:7140)
at android.view.View.performClickInternal(View.java:7117)
at android.view.View.access$3500(View.java:801)
at android.view.View$PerformClick.run(View.java:27351)
at android.os.Handler.handleCallback(Handler.java:883)
at android.os.Handler.dispatchMessage(Handler.java:100)
at android.os.Looper.loop(Looper.java:214)
at android.app.ActivityThread.main(ActivityThread.java:7356)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
Caused by: android.system.ErrnoException: open failed: ENOENT (No such file or directory)
at libcore.io.Linux.open(Native Method)
at libcore.io.ForwardingOs.open(ForwardingOs.java:167)
at libcore.io.BlockGuardOs.open(BlockGuardOs.java:252)
at libcore.io.ForwardingOs.open(ForwardingOs.java:167)
at android.app.ActivityThread$AndroidOs.open(ActivityThread.java:7255)
at libcore.io.IoBridge.open(IoBridge.java:482)
... 23 more

Any help is appreciated.

 

[DonManfred]

java.io.FileNotFoundException: /data/user/0/b4a.CheeseDiary/files/virtual_assets/table.csv: open failed: ENOENT (No such file or directory)

i did not check your code but: Are you trying to save the csv to File.DirAssets? DirAssets is READONLY

 

[DonManfred]

change the button sub...

Sub Button1_Click
    ExportTableToCSV
    'If File.Exists(File.DirDefaultExternal, "table.csv") = False Then
    'File.Copy(File.DirAssets, "table.csv", File.DirDefaultExternal, "table.csv") ' as the file does not exists in assets it can not be copied...
    'End If
End Sub

 

[TonyVerberne]

Thanks DonManfred. Yes I realise that File.DirAssets is read only and not accessible. I am trying to read from a file that it is in the DirAssets folder and save it as a .csv file in the DirDefaultExternal folder. In that way, users of the app will be able to save their records (of cheeses that they have made, a noble thing) prior to any app updates or enhancements.
Tony Verberne

 

[Erel]

1. Watch the Runtime Permissions video tutorial. You should never use File.DirDefaultExternal.

2. Files in File.DirInternal are not erased during updates.
3. Files in RP.GetSafeDirDefaultExternal are deleted when the app is uninstalled. Not many good reasons to use it instead of File.DirInternal.

 

[TonyVerberne]

Thank you for your reply Erel. I listened to the Runtime Permissions tutorial and it is clear that using File.DirInternal is not a good idea.

It is good that Files in File.DirInternal are not erased during updates. Nevertheless, if I wanted to export the data in the CSVfile to Excel, how is that done safely?
That's really what I am trying to do.

 

[Erel]

is clear that using File.DirInternal is not a good idea.

It is a good idea.

Nevertheless, if I wanted to export the data in the CSVfile to Excel, how is that done safely?

I'm not sure that I understand the question.

 

[TonyVerberne]

Sorry Erel, I meant 'File.DirDefaultExternal'.

I had better explain myself more clearly. If I go to my phone's storage folder and drill down to 'storage/android' I can't see the data that I have stored in the diary (because it is located in DirAssets?).
I would like to have a way to export the data (in this case, records of cheeses that I, and my artisanal home cheesemaker colleagues, make and record. Ideally, when 'Export' is clicked Excel opens and the file can be saved in some location. Thanks for your help as always and I apologise if I appear obtuse.

 

[Erel]

File Explorers can access RP.GetSafeDirDefaultExternal. Another option is to request the write external storage permission and save the file in File.DirRootExternal. It will be easier for the user to find it.

 

[TonyVerberne]

Thanks for this suggestion Erel.