Xamarin Forms app throws 'SQLite.SQLiteException: Could not open database file' - sqlite

Question

Xamarin Forms app throws following error during on click on Navigation Button.
If I comment the following method DisplaySoccerStatus(); in the SoccerDailyStatus class then the app will work. So I assume, few records in the database which are null is causing the issue ? Not sure, how can I resolve the problem ?
SQLite.SQLiteException: Could not open database file: /data/user/0/com.companyname.soccerapp/files/.config/soccerpep (CannotOpen
public partial class SoccerDailyStatus : ContentPage
{
private SQLiteConnection conn;
SoccerAvailability status;
public SoccerDailyStatus(SoccerAvailability soccerStatus)
{
InitializeComponent();
status = soccerStatus;
BindingContext = status;
//DisplaySoccerStatus();
}
protected override async void OnAppearing()
{
conn = DependencyService.Get<Isqlite>().GetConnection();
conn.CreateTable<SoccerAvailability>();
base.OnAppearing();
async Task DisplaySoccerStatus()
{
var datetoday = DateTime.Now.ToString("ddMMyyyy");
//List<SoccerAvailability> myList = (from x in conn.Table<SoccerAvailability>() select x).ToList();
List<SoccerAvailability> myList = (from x in conn.Table<SoccerAvailability>().Where(x => x.CurrentDate == datetoday) select x).ToList();
if (myList != null)
{
SoccerAvailability soccerAvailability = new SoccerAvailability();
soccerAvailability.SoccerStatus = myList[0].SoccerStatus;
soccerAvailability.CurrentDate = DateTime.Now.ToString("ddMMyyyy");
await Navigation.PushAsync(new SoccerDailyStatus(soccerAvailability) { });
}
else
{
await DisplayAlert("Notification", "Unable to proccess status", "Cancel");
}
}
await DisplaySoccerStatus();
}
}
}
Stack Trace:
05-04 13:51:12.462 D/Mono (23709): DllImport attempting to load: '__Internal'.
05-04 13:51:12.462 D/Mono (23709): DllImport loaded library '(null)'.
05-04 13:51:12.462 D/Mono (23709): DllImport searching in: '__Internal' ('(null)').
05-04 13:51:12.462 D/Mono (23709): Searching for 'monodroid_get_system_property'.
05-04 13:51:12.462 D/Mono (23709): Probing 'monodroid_get_system_property'.
05-04 13:51:12.462 D/Mono (23709): Found as 'monodroid_get_system_property'.
05-04 13:51:12.462 D/Mono (23709): DllImport searching in: '__Internal' ('(null)').
05-04 13:51:12.462 D/Mono (23709): Searching for 'monodroid_free'.
05-04 13:51:12.462 D/Mono (23709): Probing 'monodroid_free'.
05-04 13:51:12.462 D/Mono (23709): Found as 'monodroid_free'.
05-04 13:51:12.904 D/Mono (23709): DllImport searching in: 'e_sqlite3' ('libe_sqlite3.so').
05-04 13:51:12.904 D/Mono (23709): Searching for 'sqlite3_changes'.
05-04 13:51:13.123 I/art (23709): Starting a blocking GC Explicit
05-04 13:51:13.132 I/art (23709): Explicit concurrent mark sweep GC freed 206(21KB) AllocSpace objects, 0(0B) LOS objects, 39% free, 3MB/5MB, paused 651us total 8.285ms
05-04 13:51:13.134 D/Mono (23709): GC_TAR_BRIDGE bridges 87 objects 901 opaque 262 colors 87 colors-bridged 87 colors-visible 87 xref 0 cache-hit 0 cache-semihit 0 cache-miss 0 setup 0.03ms tarjan 0.19ms scc-setup 0.04ms gather-xref 0.02ms xref-setup 0.02ms cleanup 0.74ms
05-04 13:51:13.134 D/Mono (23709): GC_BRIDGE: Complete, was running for 11.21ms
05-04 13:51:13.135 D/Mono (23709): GC_MINOR: (Nursery full) time 7.23ms, stw 7.85ms promoted 1963K major size: 2848K in use: 2132K los size: 1024K in use: 55K
05-04 13:51:13.306 D/Mono (23709): GC_TAR_BRIDGE bridges 0 objects 0 opaque 0 colors 0 colors-bridged 0 colors-visible 87 xref 0 cache-hit 0 cache-semihit 0 cache-miss 0 setup 0.03ms tarjan 0.19ms scc-setup 0.04ms gather-xref 0.02ms xref-setup 0.02ms cleanup 0.02ms
05-04 13:51:13.306 D/Mono (23709): GC_BRIDGE: Complete, was running for 0.15ms
05-04 13:51:13.307 D/Mono (23709): GC_MINOR: (Nursery full) time 5.49ms, stw 5.88ms promoted 2025K major size: 4992K in use: 4209K los size: 1024K in use: 55K
05-04 13:51:13.468 D/Mono (23709): GC_TAR_BRIDGE bridges 0 objects 0 opaque 0 colors 0 colors-bridged 0 colors-visible 87 xref 0 cache-hit 0 cache-semihit 0 cache-miss 0 setup 0.03ms tarjan 0.19ms scc-setup 0.04ms gather-xref 0.02ms xref-setup 0.02ms cleanup 0.03ms
05-04 13:51:13.468 D/Mono (23709): GC_BRIDGE: Complete, was running for 0.26ms
05-04 13:51:13.468 D/Mono (23709): GC_MINOR: (Nursery full) time 6.25ms, stw 6.64ms promoted 1963K major size: 7024K in use: 6222K los size: 1024K in use: 55K
05-04 13:51:13.629 D/Mono (23709): GC_TAR_BRIDGE bridges 0 objects 0 opaque 0 colors 0 colors-bridged 0 colors-visible 87 xref 0 cache-hit 0 cache-semihit 0 cache-miss 0 setup 0.03ms tarjan 0.19ms scc-setup 0.04ms gather-xref 0.02ms xref-setup 0.02ms cleanup 0.03ms
05-04 13:51:13.629 D/Mono (23709): GC_BRIDGE: Complete, was running for 0.19ms
05-04 13:51:13.629 D/Mono (23709): GC_MINOR: (Nursery full) time 7.41ms, stw 7.90ms promoted 1886K major size: 9024K in use: 8157K los size: 1024K in use: 55K
05-04 13:51:13.817 D/Mono (23709): GC_TAR_BRIDGE bridges 0 objects 0 opaque 0 colors 0 colors-bridged 0 colors-visible 87 xref 0 cache-hit 0 cache-semihit 0 cache-miss 0 setup 0.03ms tarjan 0.19ms scc-setup 0.04ms gather-xref 0.02ms xref-setup 0.02ms cleanup 0.03ms
05-04 13:51:13.817 D/Mono (23709): GC_BRIDGE: Complete, was running for 0.19ms
05-04 13:51:13.817 D/Mono (23709): GC_MINOR: (Nursery full) time 9.31ms, stw 9.72ms promoted 1818K major size: 10896K in use: 10021K los size: 1024K in use: 55K
05-04 13:51:14.140 I/art (23709): Starting a blocking GC Explicit
05-04 13:51:14.147 I/art (23709): Explicit concurrent mark sweep GC freed 156(9KB) AllocSpace objects, 0(0B) LOS objects, 39% free, 3MB/5MB, paused 599us total 6.464ms
05-04 13:51:14.147 D/Mono (23709): GC_TAR_BRIDGE bridges 29 objects 29 opaque 0 colors 29 colors-bridged 29 colors-visible 29 xref 0 cache-hit 0 cache-semihit 0 cache-miss 0 setup 0.04ms tarjan 0.03ms scc-setup 0.03ms gather-xref 0.02ms xref-setup 0.02ms cleanup 0.27ms
05-04 13:51:14.147 D/Mono (23709): GC_BRIDGE: Complete, was running for 7.41ms
05-04 13:51:14.147 D/Mono (23709): GC_MINOR: (Nursery full) time 7.24ms, stw 7.62ms promoted 501K major size: 11472K in use: 10539K los size: 1024K in use: 55K
05-04 13:51:14.157 D/Mono (23709): DllImport searching in: 'e_sqlite3' ('libe_sqlite3.so').
05-04 13:51:14.158 D/Mono (23709): Searching for 'sqlite3_close_v2'.
05-04 13:51:14.651 I/Choreographer(23709): Skipped 167 frames! The application may be doing too much work on its main thread.
05-04 13:51:14.688 E/EGL_emulation(23709): tid 23733: swapBuffers(531): error 0x300d (EGL_BAD_SURFACE)
05-04 13:51:14.688 W/OpenGLRenderer(23709): swapBuffers encountered EGL_BAD_SURFACE on 0x9c46bd40, halting rendering...
05-04 13:51:14.690 D/EGL_emulation(23709): eglMakeCurrent: 0xb077de80: ver 3 1 (tinfo 0x9c459e20)
Unhandled Exception:
SQLite.SQLiteException: Could not open database file: /data/user/0/com.companyname.soccerapp/files/.config/soccerpep (CannotOpen)

Answer 1

I think the problem is due to the async method DisplaySoccerStatus called in ctor.
A single data connection cannot be used simultaneously in two or more threads.
I suggest two things:
Call your DisplaySoccerStatus in async onAppearing and use await DisplaySoccerStatus. Oh, and use async Task DisplaySoccerStatus and not async void so you can know when task is finished.
The async void case is a "fire and forget": You start the task chain, but you don't care about when it's finished. When the function returns, all you know is that everything up to the first await has executed. Everything after the first await will run at some unspecified point in the future that you have no access to.
Move your connection in a singleton declared on app.xaml.xs as suggested in the official documentation