Binded TappedCommand is not triggering

2022-05-04 10:23 Funky Sloth imported from Stackoverflow

Can anyone point out why my Command is not triggering? This is my custom control

public partial class RateControl : Grid
    {
        public static readonly BindableProperty RateProperty = BindableProperty.Create(nameof(Rating), typeof(int), typeof(RateControl), 1, propertyChanged: OnRatePropertyChanged);

        private static void OnRatePropertyChanged(BindableObject bindable, object oldValue, object newValue)
        {
            if(bindable is RateControl && bindable != null && newValue is int)
            {
                (bindable as RateControl).OnRateClicked((int)newValue);
            }
        }

        public int Rating
        {
            set => SetValue(RateProperty, value);
            get => (int)GetValue(RateProperty);
        }

        public ICommand OnRateSelectedCommand { get; set; }

        public RateControl()
        {
            InitializeComponent();
            OnRateSelectedCommand = new Command<int>(OnRateClicked);
        }

        private void OnRateClicked(int rating)
        {
            Rating = rating;
            ChangeStar(Rating);
        }

        private void ChangeStar(int starcount)
        {
            for (int i = 1; i <= starcount; i++)
            {
                (FindByName($"star{i}") as Label).Text = RsrIcon.StarFull;
            }

            for (int i = starcount + 1; i <= 5; i++)
            {
                (FindByName($"star{i}") as Label).Text = RsrIcon.StarEmpty;
            }
        }
    }

And this is my Xaml

<Grid xmlns="http://xamarin.com/schemas/2014/forms" 
      xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
      x:Class="Mobile.Controls.RateControl"
      xmlns:common="clr-namespace:Mobile.Common"
      xmlns:control="clr-namespace:Mobile.Controls"
      RowDefinitions="Auto"
      x:Name="component"
      ColumnDefinitions="30,30,30,30,30"
      ColumnSpacing="10">
    
    <control:TappableLabel FontSize="Large"
                           x:Name="star1"
                           TappedCommand="{x:Binding OnRateSelectedCommand, Source={x:Reference component}}"
                           TappedCommandParameter="1"
                           Text="{Static common:RsrIcon.StarEmpty}"
                           TextColor="{StaticResource RsrYellow}"
                           VerticalOptions="Center"/>

.....

So the TappableLabel is just a custom TappedGesture, The thing is upon clicking the RateControl either be StarFull or StarEmpty. The initialization of the command is working, but upon clicking nothing is happening.

2 answers

answered 2022-05-04 13:41 ToolmakerSteve
I've never seen {x:Binding ... used with Xamarin Forms.
Change it to {Binding ...:
```
... TappedCommand="{Binding OnRateSelectedCommand, Source={x:Reference component}}"
```
Optionally, add as last line in constructor:
```
    BindingContext = this;
```
Then you can do binding simply with {Binding OnRateSelectedCommand}:
```
... TappedCommand="{Binding OnRateSelectedCommand}"
```

answered 2022-05-05 03:13 ColeX

The generic type of Command should be string not int.

Modify your code as below

//xaml
TappedCommand="{Binding OnRateSelectedCommand}"

public RateControl()
{
   InitializeComponent();
   OnRateSelectedCommand = new Command<string>(OnRateClicked);
   BindingContext = this;
}

private void OnRateClicked(string rating)
{

}

See also questions close to this topic

Command failed: xcrun instruments -s

I want to run my react native app on a real ios device with this line :

npx react-native run-ios --udid SOME-UDID

but i got this error :

xcrun: error: sh -c '/Applications/Xcode.app/Contents/Developer/usr/bin/xcodebuild -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -find instruments 2> /dev/null' failed with exit code 17664: (null) (errno=No such file or directory)
xcrun: error: unable to find utility "instruments", not a developer tool or in PATH
error Command failed: xcrun instruments -s
xcrun: error: sh -c '/Applications/Xcode.app/Contents/Developer/usr/bin/xcodebuild -sdk /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk -find instruments 2> /dev/null' failed with exit code 17664: (null) (errno=No such file or directory)
xcrun: error: unable to find utility "instruments", not a developer tool or in PATH

everything is ok on simulator

I'm using XCODE 13

IOS Launcher in android studio

I'm trying to change the whole Android OS installed app icons into IOS icons, please help me with the proper code or library for android kotlin

Debugging undefined is not an object (evaluating 'Object.keys(routeConfigs)')

I'm using Expo and React Native to create a simple iOS app. I am currently getting this error and have no idea how to fix it. I've tried various other solutions on Stack Overflow to no avail.

My code is:

import 'react-native-gesture-handler';
import React from 'react';
import { createStackNavigator } from 'react-navigation-stack';
import { NavigationContainer } from '@react-navigation/native';
import HomeScreen from './src/screens/HomeScreen';

const Stack = createStackNavigator();

export default function App() {
  return (
    <NavigationContainer>
    <Stack.Navigator>
      <Stack.Screen name="Home" component={HomeScreen} />
    </Stack.Navigator>
    </NavigationContainer>
  );
}

Here is my HomeScreen.js

import React from 'react';
import { Text, View } from 'react-native';

export default function HomeScreen () {
  return (
    <View>
      <Text>Welcome Home!</Text>
    </View>
  )
}

My packages:

  "packages": {
    "": {
      "name": "safey",
      "version": "1.0.0",
      "dependencies": {
        "@react-native-community/masked-view": "^0.1.11",
        "@react-navigation/native": "^6.0.10",
        "@react-navigation/stack": "^6.0.10",
        "expo": "~45.0.0",
        "expo-splash-screen": "~0.15.1",
        "expo-status-bar": "~1.3.0",
        "react": "17.0.2",
        "react-dom": "17.0.2",
        "react-native": "0.68.1",
        "react-native-gesture-handler": "^2.4.2",
        "react-native-reanimated": "^2.8.0",
        "react-native-safe-area-context": "^4.2.5",
        "react-native-screens": "^3.13.1",
        "react-native-web": "0.17.7",
        "react-navigation": "^4.4.4",
        "react-navigation-stack": "^2.10.4"
      },

Change item control property of checked listview item Xamarin.Forms

Hy, I am trying to show a comment input if the item checkbox is checked and hide it else, i have this XAML

<ListView ItemsSource="{Binding TaskItems}" x:Name="TasksItems" HasUnevenRows="True" VerticalScrollBarVisibility="Default" SelectionMode="None">
<ListView.ItemTemplate>
    <DataTemplate>
        <ViewCell>
            <StackLayout IsVisible="True" Orientation="Vertical">
                <Grid BackgroundColor="White">
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="*"></ColumnDefinition>
                    </Grid.ColumnDefinitions>

                    <Grid.RowDefinitions>
                        <RowDefinition Height="auto" />
                    </Grid.RowDefinitions>

                    <StackLayout Grid.Column="0" Grid.Row="0">
                        <input:CheckBox Type="Box" IsChecked="{Binding TaskChecked , Mode=TwoWay}"/>
                    </StackLayout>

                    <StackLayout Grid.Column="0" Grid.Row="1" IsVisible="{Binding CommentRequired}">
                        <Entry BackgroundColor="White" PlaceholderColor="Black" HeightRequest="40" TextColor="Black"/>
                    </StackLayout>
                </Grid>
            </StackLayout>
        </ViewCell>
    </DataTemplate>
</ListView.ItemTemplate>

and i have this c# code to read the items from database

public class TaskData
{
    public bool TaskChecked { get; set; }
    public bool CommentRequired { get; set; }
}

public partial class HomePage : ContentPage
{
    public HomePage()
    {
        ObservableCollection<TaskData> TaskItems { get; set; }
        ObservableCollection<TaskData> TasksList;
        TaskItems = new ObservableCollection<TaskData>();

        //Loop the tasks from database result
        While...
           TaskItems.Add(new TaskData
           {
               TaskChecked = false,
               CommentRequired = false,
           });
        //End Loop

        TasksListView.ItemsSource = TaskItems;
    }
}

Now i need to add a "CheckChanged" event to show the comment Entry (IsVisible="True") when the user check the checkbox of the targed listview item

Thanks

Uploading Image files from Xamarin App to Gallery and Azure

I am working on a development (Android, IOS) that requires uploading Images files to an Azure Storage, this images can be taken from the gallery or with the device's camera.

For this I have implemented the following:

-Image Capture (I'm using Xamarin.Essentials.CapturePhotoAsync()) (Solved) -Images from Gallery (I'm using Xamarin.Essentials.PickPhotoAsync()) (Solved)

Both actions are stored in a List that will finally uploaded to the azure storage.

First question: Is this the best "approach" to upload files to storage? Is there a better practice than storing all this information in a list and finally uploading it?

In addition to this, I have a new requirement and that is that the captured images can be stored in the device's gallery. Hence my second question....

Which is the best way to get it to work on both Android and IOS? Tried some methods, but not everything works properly...

The libraries that can possibly solve this are a bit outdated or don't work in all cases....

(Xam.Plugin.Media) Have some issues on resent Android devices (Xamarin.MediaGallery) works great on Android but on IOS it's another story 😕 Dependency Services: it is the most successful and a different angle than nugets but... it currently has some things deprecated like storage routes in Android for save in Gallery....

I would appreciate your recommendations.

Put an image from camera with migradoc or pdfsharp with xamarin forms

I have a problem that I can't put an image from the camera to the pdf. It put the same error "Image could not read". How can I do it? This is the path they gave me when I take a photo =

"/storage/emulated/0/Android/data/com.companyname.atecresacalculator/files/Pictures/fotoparapdf_12.jpg"

code from CompartirInformacion(SharedInformation):

namespace AtecresaCalculator.Service
{
    public class CompartirInformacion
    {
        public static string x;
        public static string y;
    }   
}

where I added into the pdf:

Row row = table.AddRow();
table.Rows.HeightRule = RowHeightRule.Auto;
row.Cells[0].AddParagraph(text);
row.Cells[0].VerticalAlignment = VerticalAlignment.Center;
row.Cells[1].AddParagraph(texto);
row.Cells[1].AddImage(FromFile(CompartirInformacion.y));
row.Cells[1].VerticalAlignment = VerticalAlignment.Center;

Clicked to take the photo:

private async void sacarFoto_Clicked(object sender, EventArgs e)
{
    await CrossMedia.Current.Initialize();
    if (!CrossMedia.Current.IsCameraAvailable || !CrossMedia.Current.IsTakePhotoSupported)
    {
        await DisplayAlert("Error en la cámara", "Activa los permisos para usar cámara", "Ok");
        return;
    }

    var file = await CrossMedia.Current.TakePhotoAsync(new Plugin.Media.Abstractions.StoreCameraMediaOptions
    {
        PhotoSize = Plugin.Media.Abstractions.PhotoSize.Small,
        Name = "fotoparapdf.jpg",
        CompressionQuality = 100,
        DefaultCamera = Plugin.Media.Abstractions.CameraDevice.Rear,
    });

    if (file == null)
        return;

    await DisplayAlert("Ruta de la foto", file.Path, "Ok");

    CompartirInformacion.y = file.Path;
}

Related questions

Binded TappedCommand is not triggering

2 answers

See also questions close to this topic