How to delete data from SQLite database in Xamarin - xamarin

Question

This is my DisplayData.xaml:
<ContentPage.Content>
<StackLayout>
<ListView x:Name="RecordList"
ItemSelected="OnItemSelected">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<StackLayout Orientation="Horizontal"
HorizontalOptions="FillAndExpand"
Margin="20, 10, 20, 0" >
<Label Text="{Binding Text}"
HorizontalOptions="StartAndExpand"
TextColor="WhiteSmoke"/>
</StackLayout>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
<Entry x:Name="TextEntry"
Placeholder="hehe"
IsVisible="False"/>
<Entry x:Name="IDEntry"
Placeholder="hehe"
IsVisible="False"/>
</StackLayout>
</ContentPage.Content>
This is my DisplayData.xaml.cs:
public partial class DisplayData : ContentPage
{
string _dbPath = Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal), "myDatabase.db3");
SpeechRecTable _speech = new SpeechRecTable();
public DisplayData()
{
InitializeComponent();
}
protected override void OnAppearing()
{
base.OnAppearing();
var db = new SQLiteConnection(_dbPath);
RecordList.ItemsSource = db.Table<SpeechRecTable>().OrderBy(x => x.Text).ToList();
}
private void OnItemSelected(object sender, SelectedItemChangedEventArgs e)
{
_speech = (SpeechRecTable)e.SelectedItem;
TextEntry.Text = _speech.Text;
IDEntry.Text = _speech.Id.ToString();
Device.BeginInvokeOnMainThread(async () =>
{
await Navigation.PushAsync(new RecordContent(TextEntry.Text, IDEntry.Text));
});
}
}
When a listview Item is selected it looks like this on my RecordContent.xaml:
When I click my delete button it does not delete that record, this the code for delete:
private async void BtnDelete_Clicked(object sender, EventArgs e)
{
var db = new SQLiteConnection(_dbPath);
db.Table<SpeechRecTable>().Delete(x => x.Id == _speech.Id);
await Navigation.PopAsync();
}
even if I use:
db.Delete<SpeechRecTable>(Id);
instead of:
db.Table<SpeechRecTable>().Delete(x => x.Id == _speech.Id);
The Item will still not be deleted, and most of the tutorials that or guides that I have encountered has only one view page with the add,delete, and update button. I am trying to separate the delete and update button, my update button works just fine, but the delete is not working, it just immediately execute this: await Navigation.PopAsync(); and then nothing happens.

Answer 1

I have already solved my problem, by using this:
private void BtnDelete_Clicked(object sender, EventArgs e)
{
Device.BeginInvokeOnMainThread(async () =>
{
var result = await this.DisplayAlert("Delete Item", "Are you sure that you want to DELETE this record?", "Yes", "No");
if (result)
{
var db = new SQLiteConnection(_dbPath);
_speech.Id = Convert.ToInt32(DataIdEntry.Text);
db.Table<SpeechRecTable>().Delete(x => x.Id == _speech.Id);
await Navigation.PopAsync();
}
else
{
}
});
}