Get data from Database using Controller xamarin Forms (MVC) - xamarin.forms

Question

I need a help..
I need to get data from database using Controller.. But nothing happens when I do it.
My api is php codeigniter and i'm using X-API-Key.. I want to use It in MVC structure, because I need my view be navigable.
HttpClient
public class HttpClient
{
private Dictionary<string, string> _headers;
private HttpClient restClient;
public HttpClient(Dictionary<string, string> headers)
{
if (headers != null) _headers = headers;
else _headers = new Dictionary<string, string>();
}
public string this[string Key]
{
get
{
return _headers[Key];
}
set
{
_headers[Key] = value;
}
}
///<Summary>
/// HTTP GET REQUEST
///</Summary>
public async Task<HttpResponse<T>> ExcecuteAsync<T>(Method method, string baseUrl, Dictionary<string, object> formdata = null)
{
var client = new RestClient(baseUrl);
var request = new RestRequest(method);
foreach(var header in _headers)
{
request.AddHeader(header.Key, header.Value);
}
if(formdata != null)
{
foreach(var item in formdata)
{
request.AddParameter(item.Key, item.Value);
}
}
IRestResponse response = null;
Exception ex = null;
try
{
response = await client.ExecuteTaskAsync(request);
}
catch(Exception _ex)
{
ex = _ex;
}
var httpresponse = new HttpResponse<T>
{
Response = response
};
if (response == null)
{
httpresponse.Status = new StatusResponse
{
code = -1,
message = $"Nao se pode obter resposta do servidor, stacktrace:{ex.StackTrace}"
};
return httpresponse;
}
var jsonresult = response.Content;
if (response.StatusCode == System.Net.HttpStatusCode.OK)
{
var telement = JsonConvert.DeserializeObject<T>(jsonresult);
httpresponse.Result = telement;
}else if(response.StatusCode == 0)
{
httpresponse.Status = new StatusResponse
{
code = 0,
message = $"Nao se pode obter resposta do servidor"
};
}
else
{
var telement = JsonConvert.DeserializeObject<StatusResponse>(jsonresult);
httpresponse.Status = telement;
}
return httpresponse; //null
}
This is my App.xaml - where i have my x-api-key
App.RestClient = new HttpClient(new Dictionary<string, string>
{
{"X-API-Key", "926ff4c0-d86e-421f-9192-82ac52650f5c" }
});
App.BaseUrl = "http://10.156.96.80/apiuthomi";
protected override async void OnStart()
{
var ListasHospitais = await new HospitalService(App.RestClient).all();
MainPage = new ListHospital(ListasHospitais);
}
This is ListHospital.xaml
<StackLayout>
<ListView
HasUnevenRows="True"
SeparatorVisibility="Default"
x:Name="ListasHospitais"
IsPullToRefreshEnabled="True"
Margin="10">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<Grid Padding="10" RowSpacing="10" ColumnSpacing="10" BackgroundColor="White" Margin="0 , 0 , 0, 10">
<Grid.RowDefinitions>
<RowDefinition Height="auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Label Grid.Column="1"
VerticalOptions="End"
Text="{Binding Nome}"
MaxLines="1"
LineBreakMode="TailTruncation"
FontAttributes="Bold"
/>
<Label Grid.Column="1"
Grid.Row="1"
Text="{Binding Detalhes}"
VerticalOptions="Start"
LineBreakMode="TailTruncation"
MaxLines="2"
/>
</Grid>
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
This is my ListHospital.xaml.cs
public partial class ListHospital : ContentPage
{
public ObservableCollection<Cliente> _clientes;
public ListHospital(List<Cliente>clientes)
{
InitializeComponent();
NavigationPage.SetHasNavigationBar(this, false);
_clientes = new ObservableCollection<Cliente>();
ListasHospitais.ItemsSource = _clientes;
foreach(var cliente in clientes)
{
_clientes.Add(cliente);
}
}
public void voltar_Click(object sender, System.EventArgs e)
{
Navigation.PopAsync();
}
}
HospitalService = where i will write all methods
public class HospitalService
{
private HttpClient _restclient;
public HospitalService(HttpClient restclient)
{
if (restclient != null) _restclient = restclient;
else throw new NullReferenceException("http nao pode ser nulo");
}
public async Task<List<Cliente>>all()
{
var response = await _restclient.GetAsync<List<Cliente>>("http://10.156.96.80/apiuthomi/cliente/all");
if (response.Result != null) return response.Result;
return new List<Cliente>();
}
}
until here everything is going well and it's working.. but the problem is that my view listHospital os no longer clickable.. like I want tho make this page be navigable...
this public ListHospital(List<Cliente>clientes)does not allow the clicked method to be valid in my view

Answer 1

I can't do await Navigation.PushAsync(new ListHospital()) , It give
me an error
this is because your ListHosptial page does not have a default (empty) constructor and you are not passing the required data. You can fix this by adding an default constructor
public ListHospital()
{
InitializeComponent();
NavigationPage.SetHasNavigationBar(this, false);
...
}
if you do this then ListHospital needs to load it's own data. The easiest way to do this is probably to add a call to your services in the OnAppearing method
public override async void OnAppearing()
{
// call services to load data and assign ItemsSource
var data = await new HospitalService(App.RestClient).all();
ListasHospitais.ItemsSource = data;
}