Android Question Problem with list

[mrossen]

Hi,

I have a dataset I get from a mysql database.

If I get the data right I store the record in a txt file with file.writelist

If I dont have data connection I read the dataset with file.readlist, but something seems not to be done right.

I hope someone can see what I have made right

I get no error but the app craches.

Sub JobDone(Job As HttpJob)
  
    Dim oldData, newData As String
    Dim partNoAll As String
      
    brand_cars.Initialize
      
    Dim lType As List
  
    lType.Initialize
  
  
  
    ListViewCars.TwoLinesLayout.Label.Textsize = 16
    ListViewCars.TwoLinesLayout.SecondLabel.Textsize = 14
  
      
    ProgressDialogHide
    If Job.Success Then
    Dim res As String
        res = Job.GetString
  
        Dim parser As JSONParser
        parser.Initialize(res)
        Select Job.JobName
            Case brand
          
                brand_list = parser.NextArray 'returns a list with maps
                 
                For i = 0 To brand_list.Size - 1
                    mAll = brand_list.Get(i)
                    partNoAll = mAll.Get("partno")

                    newData = mAll.Get("brand") & " - " & mAll.Get("model") & " - " & mAll.Get("engine") & " - " & mAll.Get("yearfrom") & " - " & mAll.Get("fuel") & " - " & mAll.Get("variant") & " - " & partNoAll.CharAt(5)
                                      
                    If newData <> oldData Then
                        brand_cars.Add(brand_list.Get(i))
                    End If
                      
                    oldData = mAll.Get("brand") & " - " & mAll.Get("model") & " - " & mAll.Get("engine") & " - " & mAll.Get("yearfrom") & " - " & mAll.Get("fuel") & " - " & mAll.Get("variant")  & " - " & partNoAll.CharAt(5)
                  
                Next
          
                File.WriteList(File.DirRootExternal, "ListBrand.txt", brand_cars)
              
                getCars
              
        End Select
    Else
        ToastMessageShow("No internet connection", True)
      

        brand_cars = File.ReadList(File.DirRootExternal, "ListBrand.txt")
        getCars
      
      
    End If
    Job.Release

                  
                  
End Sub

 

[DonManfred]

I get no error but the app craches

then you should look into the log. I´m sure there is an error.

 

[mrossen]

Yes there are, but first later in the code, when I try to access the. For me it looks like I load an empty list

Error:


Error occurred on line: 335 (main)
java.lang.ClassCastException: java.lang.String cannot be cast to anywheresoftware.b4a.objects.collections.Map$MyMap
at anywheresoftware.b4a.objects.collections.Map.Get(Map.java:65)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:636)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:302)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:238)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:121)
at anywheresoftware.b4a.BA$3.run(BA.java:332)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:155)
at android.app.ActivityThread.main(ActivityThread.java:5696)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)

at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1028)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:823)

 

[mrossen]

But if I make a breakpoint at the codeline : getCars after I have read the list, I get no error.

But if I then try to hover "brand_cars" to see what is in the list, the app terminates

Mogens

 

[DonManfred]

Try to create a small example which shows this problem and upload this project here (IDE -> File -> Export as Zip)

 

[mrossen]

Ok, thank you. I will do that later

 

[mrossen]

Now I have made a test app

Start the app with internet connection and it will list car brands in the log.

Disable internet connection and start the app Again.

It will now crach.

 

[Erel]

File.ReadList returns a list of strings. It reads the text file and returns each line as a single string item.

If you are trying to save non-string values then you should use KeyValueStore class.

 

[mrossen]

That Works perfect,

Mogens