Xamarin.Tip – Borderless Editor

I previously put out a post on removing the border of a Xamarin.Forms Entry which was then used to create a custom PinView as well as a MaterialEntry that follows the material design standards for text fields. Check those out here:

In this post, we’ll apply some of the same principles to create a BorderlessEditor. It’s going to use a simple custom renderer, although this could and should be done using an Effect if being used on its own. However, this BorderlessEditor will be the foundation for future controls.

You can find this code as part of my library in progress to create Material Design Form controls for Xamarin.Forms – https://github.com/SuavePirate/SuaveControls.MaterialFormControls.

Let’s get started with our custom control by first creating a custom subclass of Xamarin.Forms.Editor followed by a custom renderer class for iOS, Android, and UWP that kills the border.

BorderlessEditor.cs

namespace SuaveControls.MaterialForms
{
    public class BorderlessEditor : Editor
    {
    }
}

Nothing special here since we are using the default behavior of the Editor.

Android

Now let’s create an Android custom renderer.

BorderlessEditorRenderer.cs – Android

[assembly: ExportRenderer(typeof(BorderlessEditor), typeof(BorderlessEditorRenderer))]
namespace SuaveControls.MaterialForms.Android.Renderers
{
    public class BorderlessEditorRenderer : EditorRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<Editor> e)
        {
            base.OnElementChanged(e);
            if (e.OldElement == null)
            {
                Control.Background = null;

                var layoutParams = new MarginLayoutParams(Control.LayoutParameters);
                layoutParams.SetMargins(0, 0, 0, 0);
                LayoutParameters = layoutParams;
                Control.LayoutParameters = layoutParams;
                Control.SetPadding(0, 0, 0, 0);
                SetPadding(0, 0, 0, 0);
            }
        }
    }
}

We simple kill the default padding and margins while setting the Background property to null. This Background is what creates the drawable underline for the AppCompat Editor.

iOS

Follow with an iOS renderer.

BorderlessEditorRenderer.cs – iOS

[assembly: ExportRenderer(typeof(BorderlessEditor), typeof(BorderlessEditorRenderer))]
namespace SuaveControls.MaterialForms.iOS.Renderers
{
    public class BorderlessEditorRenderer : EditorRenderer
    {
        public static void Init() { }
        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            base.OnElementPropertyChanged(sender, e);

            Control.Layer.BorderWidth = 0;
        }
    }
}

All we do here is set the BorderWidth to 0.

UWP

Lastly a renderer for UWP

BorderlessEditorRenderer.cs – UWP


[assembly: ExportRenderer(typeof(BorderlessEditor), typeof(BorderlessEditorRenderer))]

namespace SuaveControls.MaterialForms.UWP.Renderers
{
    public class BorderlessEditorRenderer : EditorRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<Editor> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
            {
                Control.BorderThickness = new Windows.UI.Xaml.Thickness(0);
                Control.Margin = new Windows.UI.Xaml.Thickness(0);
                Control.Padding = new Windows.UI.Xaml.Thickness(0);
            }
        }
    }
}

Similar to how we did it on Android, we set both the Margin and Padding to 0 and also set the BorderThickness to a 0’d Thickness.

Using the BorderlessEditor

Now you can use the BorderlessEditor in your XAML or C# code:

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:ExampleMaterialApp"
             xmlns:suave="clr-namespace:SuaveControls.MaterialForms;assembly=SuaveControls.MaterialForms"
             x:Class="ExampleMaterialApp.MainPage">

    <ScrollView>
        <StackLayout Spacing="16" Margin="16" BackgroundColor="Blue">
            <Label Text="Borderless Editor!" Margin="32" HorizontalOptions="Center" HorizontalTextAlignment="Center"/>
            <suave:BorderlessEditor BackgroundColor="Black" TextColor="White" HeightRequest="300" Margin="32"/>

        </StackLayout>
    </ScrollView>

</ContentPage>

Check out those results on iOS:

If you like what you see, don’t forget to follow me on twitter @Suave_Pirate, check out my GitHub, and subscribe to my blog to learn more mobile developer tips and tricks!

Interested in sponsoring developer content? Message @Suave_Pirate on twitter for details.

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Xamarin.Tip – Borderless TimePicker

I previously put out a post on removing the border of a Xamarin.Forms Entry which was then used to create a custom PinView as well as a MaterialEntry that follows the material design standards for text fields. I also added a post just like this one that talks about creating a BorderlessPicker. Check those out here:

In this post, we’ll do exactly what we did with the BorderlessPicker, but apply it to the Xamarin.Forms.TimePicker control to remove the border. This would ideally be done using an Effect, however we will be using this control in a later post to create a MaterialTimePicker to fit the Material Design standards for form inputs, so we will create custom renderers for Android, iOS, and UWP.

You can find this code as part of my library in progress to create Material Design Form controls for Xamarin.Forms – https://github.com/SuavePirate/SuaveControls.MaterialFormControls.

Let’s get started with our custom control by first creating a custom subclass of Xamarin.Forms.TimePicker followed by a custom renderer class for iOS, Android, and UWP that kills the border.

BorderlessTimePicker.cs

namespace SuaveControls.MaterialForms
{
    public class BorderlessTimePicker : TimePicker
    {
    }
}

Nothing special here since we are using the default behavior of the TimePicker.

Android

Now let’s create an Android custom renderer.

BorderlessTimePickerRenderer.cs – Android

[assembly: ExportRenderer(typeof(BorderlessTimePicker), typeof(BorderlessTimePickerRenderer))]
namespace SuaveControls.MaterialForms.Android.Renderers
{
    public class BorderlessTimePickerRenderer : TimePickerRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<TimePicker> e)
        {
            base.OnElementChanged(e);
            if (e.OldElement == null)
            {
                Control.Background = null;

                var layoutParams = new MarginLayoutParams(Control.LayoutParameters);
                layoutParams.SetMargins(0, 0, 0, 0);
                LayoutParameters = layoutParams;
                Control.LayoutParameters = layoutParams;
                Control.SetPadding(0, 0, 0, 0);
                SetPadding(0, 0, 0, 0);
            }
        }
    }
}

We simple kill the default padding and margins while setting the Background property to null. This Background is what creates the drawable underline for the AppCompat TimePicker.

iOS

Follow with an iOS renderer.

BorderlessTimePickerRenderer.cs – iOS

[assembly: ExportRenderer(typeof(BorderlessTimePicker), typeof(BorderlessTimePickerRenderer))]
namespace SuaveControls.MaterialForms.iOS.Renderers
{
    public class BorderlessTimePickerRenderer : TimePickerRenderer
    {
        public static void Init() { }
        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            base.OnElementPropertyChanged(sender, e);

            Control.Layer.BorderWidth = 0;
            Control.BorderStyle = UITextBorderStyle.None;
        }
    }
}

All we do here is set the BorderWidth to 0 and the BorderStyle to UITextBorderStyle.None.

UWP

Lastly a renderer for UWP

BorderlessTimePickerRenderer.cs – UWP


[assembly: ExportRenderer(typeof(BorderlessTimePicker), typeof(BorderlessTimePickerRenderer))]

namespace SuaveControls.MaterialForms.UWP.Renderers
{
    public class BorderlessTimePickerRenderer : TimePickerRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<TimePicker> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
            {
                Control.BorderThickness = new Windows.UI.Xaml.Thickness(0);
                Control.Margin = new Windows.UI.Xaml.Thickness(0);
                Control.Padding = new Windows.UI.Xaml.Thickness(0);
            }
        }
    }
}

Similar to how we did it on Android, we set both the Margin and Padding to 0 and also set the BorderThickness to a 0’d Thickness.

Using the BorderlessTimePicker

Now you can use the BorderlessTimePicker in your XAML or C# code:

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:ExampleMaterialApp"
             xmlns:suave="clr-namespace:SuaveControls.MaterialForms;assembly=SuaveControls.MaterialForms"
             x:Class="ExampleMaterialApp.MainPage">

    <ScrollView>
        <StackLayout Spacing="16" Margin="16">
            <Label Text="Borderless TimePicker!" Margin="32" HorizontalOptions="Center" HorizontalTextAlignment="Center"/>
            <suave:BorderlessTimePicker/>

        </StackLayout>
    </ScrollView>

</ContentPage>

Check out those results on iOS:

If you like what you see, don’t forget to follow me on twitter @Suave_Pirate, check out my GitHub, and subscribe to my blog to learn more mobile developer tips and tricks!

Interested in sponsoring developer content? Message @Suave_Pirate on twitter for details.

Xamarin.Tip – Borderless DatePicker

I previously put out a post on removing the border of a Xamarin.Forms Entry which was then used to create a custom PinView as well as a MaterialEntry that follows the material design standards for text fields. I also added a post just like this one that talks about creating a BorderlessPicker. Check those out here:

In this post, we’ll do exactly what we did with the BorderlessPicker, but apply it to the Xamarin.Forms.DatePicker control to remove the border. This would ideally be done using an Effect, however we will be using this control in a later post to create a MaterialDatePicker to fit the Material Design standards for form inputs, so we will create custom renderers for Android, iOS, and UWP.

You can find this code as part of my library in progress to create Material Design Form controls for Xamarin.Forms – https://github.com/SuavePirate/SuaveControls.MaterialFormControls.

Let’s get started with our custom control by first creating a custom subclass of Xamarin.Forms.DatePicker followed by a custom renderer class for iOS, Android, and UWP that kills the border.

BorderlessDatePicker.cs

namespace SuaveControls.MaterialForms
{
    public class BorderlessDatePicker : DatePicker
    {
    }
}

Nothing special here since we are using the default behavior of the DatePicker.

Android

Now let’s create an Android custom renderer.

BorderlessDatePickerRenderer.cs – Android

[assembly: ExportRenderer(typeof(BorderlessDatePicker), typeof(BorderlessDatePickerRenderer))]
namespace SuaveControls.MaterialForms.Android.Renderers
{
    public class BorderlessDatePickerRenderer : DatePickerRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<DatePicker> e)
        {
            base.OnElementChanged(e);
            if (e.OldElement == null)
            {
                Control.Background = null;

                var layoutParams = new MarginLayoutParams(Control.LayoutParameters);
                layoutParams.SetMargins(0, 0, 0, 0);
                LayoutParameters = layoutParams;
                Control.LayoutParameters = layoutParams;
                Control.SetPadding(0, 0, 0, 0);
                SetPadding(0, 0, 0, 0);
            }
        }
    }
}

We simple kill the default padding and margins while setting the Background property to null. This Background is what creates the drawable underline for the AppCompat DatePicker.

iOS

Follow with an iOS renderer.

BorderlessDatePickerRenderer.cs – iOS

[assembly: ExportRenderer(typeof(BorderlessDatePicker), typeof(BorderlessDatePickerRenderer))]
namespace SuaveControls.MaterialForms.iOS.Renderers
{
    public class BorderlessDatePickerRenderer : DatePickerRenderer
    {
        public static void Init() { }
        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            base.OnElementPropertyChanged(sender, e);

            Control.Layer.BorderWidth = 0;
            Control.BorderStyle = UITextBorderStyle.None;
        }
    }
}

All we do here is set the BorderWidth to 0 and the BorderStyle to UITextBorderStyle.None.

UWP

Lastly a renderer for UWP

BorderlessDatePickerRenderer.cs – UWP


[assembly: ExportRenderer(typeof(BorderlessDatePicker), typeof(BorderlessDatePickerRenderer))]

namespace SuaveControls.MaterialForms.UWP.Renderers
{
    public class BorderlessDatePickerRenderer : DatePickerRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<DatePicker> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
            {
                Control.BorderThickness = new Windows.UI.Xaml.Thickness(0);
                Control.Margin = new Windows.UI.Xaml.Thickness(0);
                Control.Padding = new Windows.UI.Xaml.Thickness(0);
            }
        }
    }
}

Similar to how we did it on Android, we set both the Margin and Padding to 0 and also set the BorderThickness to a 0’d Thickness.

Using the BorderlessDatePicker

Now you can use the BorderlessDatePicker in your XAML or C# code:

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:ExampleMaterialApp"
             xmlns:suave="clr-namespace:SuaveControls.MaterialForms;assembly=SuaveControls.MaterialForms"
             x:Class="ExampleMaterialApp.MainPage">

    <ScrollView>
        <StackLayout Spacing="16" Margin="16">
            <Label Text="Borderless DatePicker!" Margin="32" HorizontalOptions="Center" HorizontalTextAlignment="Center"/>
            <suave:BorderlessDatePicker/>

        </StackLayout>
    </ScrollView>

</ContentPage>

Check out those results on iOS:

If you like what you see, don’t forget to follow me on twitter @Suave_Pirate, check out my GitHub, and subscribe to my blog to learn more mobile developer tips and tricks!

Interested in sponsoring developer content? Message @Suave_Pirate on twitter for details.

Xamarin.Tip – Borderless Picker

I previously put out a post on removing the border of a Xamarin.Forms Entry which was then used to create a custom PinView as well as a MaterialEntry that follows the material design standards for text fields. Check those out here:

In this post, we’ll apply some of the same principles to create a BorderlessPicker. It’s going to use a simple custom renderer, although this could and should be done using an Effect if being used on its own. However, this BorderlessPicker will be the foundation for future controls we will create such as the MaterialPicker that applies Material Design standards to the Xamarin.Forms Picker control on Android, iOS, and UWP.

You can find this code as part of my library in progress to create Material Design Form controls for Xamarin.Forms – https://github.com/SuavePirate/SuaveControls.MaterialFormControls.

Let’s get started with our custom control by first creating a custom subclass of Xamarin.Forms.Picker followed by a custom renderer class for iOS, Android, and UWP that kills the border.

BorderlessPicker.cs

namespace SuaveControls.MaterialForms
{
    public class BorderlessPicker : Picker
    {
    }
}

Nothing special here since we are using the default behavior of the Picker.

Android

Now let’s create an Android custom renderer.

BorderlessPickerRenderer.cs – Android

[assembly: ExportRenderer(typeof(BorderlessPicker), typeof(BorderlessPickerRenderer))]
namespace SuaveControls.MaterialForms.Android.Renderers
{
    public class BorderlessPickerRenderer : PickerRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<Picker> e)
        {
            base.OnElementChanged(e);
            if (e.OldElement == null)
            {
                Control.Background = null;

                var layoutParams = new MarginLayoutParams(Control.LayoutParameters);
                layoutParams.SetMargins(0, 0, 0, 0);
                LayoutParameters = layoutParams;
                Control.LayoutParameters = layoutParams;
                Control.SetPadding(0, 0, 0, 0);
                SetPadding(0, 0, 0, 0);
            }
        }
    }
}

We simple kill the default padding and margins while setting the Background property to null. This Background is what creates the drawable underline for the AppCompat Picker.

iOS

Follow with an iOS renderer.

BorderlessPickerRenderer.cs – iOS

[assembly: ExportRenderer(typeof(BorderlessPicker), typeof(BorderlessPickerRenderer))]
namespace SuaveControls.MaterialForms.iOS.Renderers
{
    public class BorderlessPickerRenderer : PickerRenderer
    {
        public static void Init() { }
        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            base.OnElementPropertyChanged(sender, e);

            Control.Layer.BorderWidth = 0;
            Control.BorderStyle = UITextBorderStyle.None;
        }
    }
}

All we do here is set the BorderWidth to 0 and the BorderStyle to UITextBorderStyle.None.

UWP

Lastly a renderer for UWP

BorderlessPickerRenderer.cs – UWP


[assembly: ExportRenderer(typeof(BorderlessPicker), typeof(BorderlessPickerRenderer))]

namespace SuaveControls.MaterialForms.UWP.Renderers
{
    public class BorderlessPickerRenderer : PickerRenderer
    {
        public static void Init() { }
        protected override void OnElementChanged(ElementChangedEventArgs<Picker> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
            {
                Control.BorderThickness = new Windows.UI.Xaml.Thickness(0);
                Control.Margin = new Windows.UI.Xaml.Thickness(0);
                Control.Padding = new Windows.UI.Xaml.Thickness(0);
            }
        }
    }
}

Similar to how we did it on Android, we set both the Margin and Padding to 0 and also set the BorderThickness to a 0’d Thickness.

Using the BorderlessPicker

Now you can use the BorderlessPicker in your XAML or C# code:

MainPage.xaml

<?xml version="1.0" encoding="utf-8" ?>
<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
             xmlns:local="clr-namespace:ExampleMaterialApp"
             xmlns:suave="clr-namespace:SuaveControls.MaterialForms;assembly=SuaveControls.MaterialForms"
             x:Class="ExampleMaterialApp.MainPage">

    <ScrollView>
        <StackLayout Spacing="16" Margin="16">
            <Label Text="Borderless Picker!" Margin="32" HorizontalOptions="Center" HorizontalTextAlignment="Center"/>
            <suave:BorderlessPicker x:Name="PickerDemo" Title="Options"/>

        </StackLayout>
    </ScrollView>

</ContentPage>

MainPage.xaml.cs

    public partial class MainPage : ContentPage
    {
        public MainPage()
        {
            InitializeComponent();

            PickerDemo.ItemsSource = new List<string>
            {
                "Option 1",
                "Option 2",
                "Option 3",
                "Option 4"
            };
        }
    }

Check out those results on iOS:

If you like what you see, don’t forget to follow me on twitter @Suave_Pirate, check out my GitHub, and subscribe to my blog to learn more mobile developer tips and tricks!

Interested in sponsoring developer content? Message @Suave_Pirate on twitter for details.

Xamarin.Control – Xamarin.Forms MaterialEntry

Back by popular demand, bringing more Material Design controls to you Xamarin.Forms app! This time we will look at implementing the standards in Material Design’s text fields by building a MaterialEntry control. You can find the source code and example app here: https://github.com/SuavePirate/MaterialEntry but you can build your own by following this post.

Let’s build our Xamarin.Forms control to work the same on not only Android where Material Design is baked in, but also to run on iOS AND UWP. In the end, we should be able to use our floating label, set an accent color that expands on the label and underline when focused while being able to bind these properties through MVVM.

Simulator Screen Shot Jul 14, 2017, 3.42.03 PM

The first thing we need to do is create a BorderlessEntry that removes the border from our entry on all 3 platforms. I’ve done this in a previous blog post here: Xamarin.Forms Borderless Entry, so we won’t be implementing it here. This code is also in the GitHub link above.

With our BorderlessEntry we can now create our custom control WITHOUT ANY MORE CUSTOM RENDERERS!

Let’s set up the layout structure in our XAML file, and then wire up the animation logic in our code behind.

MaterialEntry.xaml

<?xml version="1.0" encoding="UTF-8"?>
<ContentView xmlns="http://xamarin.com/schemas/2014/forms"               xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"              xmlns:local="clr-namespace:SuaveControls.MaterialEntry"              x:Class="SuaveControls.MaterialEntry.MaterialEntry">
  <ContentView.Content>
        <Grid ColumnSpacing="16" Margin="0,8">
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto"/>
                <RowDefinition Height="1"/>
            </Grid.RowDefinitions>
            <Label x:Name="HiddenLabel" FontSize="10" IsVisible="False" Margin="0"/>
            <local:BorderlessEntry x:Name="EntryField" Text="{Binding Text, Mode=TwoWay}" Margin="0,12,0,0"/>
            <BoxView x:Name="BottomBorder" BackgroundColor="Gray"  Grid.Row="1" HeightRequest="1" Margin="0" HorizontalOptions="FillAndExpand"/>
            <BoxView x:Name="HiddenBottomBorder" BackgroundColor="Gray" Grid.Row="1" HeightRequest="1" Margin="0" WidthRequest="0" HorizontalOptions="Center"/>
        </Grid>
    </ContentView.Content>
</ContentView>

We set up our BorderlessEntry that will act as our formal point for entering text. We also add a label that is initially hidden and laid out on top of the BorderlessEntry. This is the label we will be using to animate the floating action that Material Design uses based while we fade out the placeholder text. The last bit is two BoxViews that act as the bottom line below the Entry. One is the unfocused which has a standard gray color, while the other has a width of 0 and will have a background color of our selected AccentColor. This will have an animated width expansion when the BorderlessEntry is focused.

Now let’s look at the animation and bindings in the code behind:

MaterialEntry.xaml.cs

public partial class MaterialEntry : ContentView
    {
        public static void Init() { }
        public static BindableProperty TextProperty = BindableProperty.Create(nameof(Text), typeof(string), typeof(MaterialEntry), defaultBindingMode: BindingMode.TwoWay);
        public static BindableProperty PlaceholderProperty = BindableProperty.Create(nameof(Placeholder), typeof(string), typeof(MaterialEntry), defaultBindingMode: BindingMode.TwoWay, propertyChanged: (bindable, oldVal, newval) =>
        {
            var matEntry = (MaterialEntry)bindable;
            matEntry.EntryField.Placeholder = (string)newval;
            matEntry.HiddenLabel.Text = (string)newval;
        });

        public static BindableProperty IsPasswordProperty = BindableProperty.Create(nameof(IsPassword), typeof(bool), typeof(MaterialEntry), defaultValue: false, propertyChanged: (bindable, oldVal, newVal) =>
        {
            var matEntry = (MaterialEntry)bindable;
            matEntry.EntryField.IsPassword = (bool)newVal;
        });
        public static BindableProperty KeyboardProperty = BindableProperty.Create(nameof(Keyboard), typeof(Keyboard), typeof(MaterialEntry), defaultValue: Keyboard.Default, propertyChanged: (bindable, oldVal, newVal) =>
        {
            var matEntry = (MaterialEntry)bindable;
            matEntry.EntryField.Keyboard = (Keyboard)newVal;
        });
        public static BindableProperty AccentColorProperty = BindableProperty.Create(nameof(AccentColor), typeof(Color), typeof(MaterialEntry), defaultValue: Color.Accent);
        public Color AccentColor
        {
            get
            {
                return (Color)GetValue(AccentColorProperty);
            }
            set
            {
                SetValue(AccentColorProperty, value);
            }
        }
        public Keyboard Keyboard
        {
            get
            {
                return (Keyboard)GetValue(KeyboardProperty);
            }
            set
            {
                SetValue(KeyboardProperty, value);
            }
        }

        public bool IsPassword
        {
            get
            {
                return (bool)GetValue(IsPasswordProperty);
            }
            set
            {
                SetValue(IsPasswordProperty, value);
            }
        }

        public string Text
        {
            get
            {
                return (string)GetValue(TextProperty);
            }
            set
            {
                SetValue(TextProperty, value);
            }
        }
        public string Placeholder
        {
            get
            {
                return (string)GetValue(PlaceholderProperty);
            }
            set
            {
                SetValue(PlaceholderProperty, value);
            }
        }
        public MaterialEntry()
        {
            InitializeComponent();
            EntryField.BindingContext = this;
            EntryField.Focused += async (s, a) =>
            {
                HiddenBottomBorder.BackgroundColor = AccentColor;
                HiddenLabel.TextColor = AccentColor;
                HiddenLabel.IsVisible = true;
                if (string.IsNullOrEmpty(EntryField.Text))
                {
                    // animate both at the same time
                    await Task.WhenAll(
                        HiddenBottomBorder.LayoutTo(new Rectangle(BottomBorder.X, BottomBorder.Y, BottomBorder.Width, BottomBorder.Height), 200),
                        HiddenLabel.FadeTo(1, 60),
                        HiddenLabel.TranslateTo(HiddenLabel.TranslationX, EntryField.Y - EntryField.Height + 4, 200, Easing.BounceIn)
                     );
                    EntryField.Placeholder = null;
                }
                else
                {
                    await HiddenBottomBorder.LayoutTo(new Rectangle(BottomBorder.X, BottomBorder.Y, BottomBorder.Width, BottomBorder.Height), 200);
                }
            };
            EntryField.Unfocused += async (s, a) =>
            {
                HiddenLabel.TextColor = Color.Gray;
                if (string.IsNullOrEmpty(EntryField.Text))
                {
                    // animate both at the same time
                    await Task.WhenAll(
                        HiddenBottomBorder.LayoutTo(new Rectangle(BottomBorder.X, BottomBorder.Y, 0, BottomBorder.Height), 200),
                        HiddenLabel.FadeTo(0, 180),
                        HiddenLabel.TranslateTo(HiddenLabel.TranslationX, EntryField.Y, 200, Easing.BounceIn)
                     );
                    EntryField.Placeholder = Placeholder;
                }
                else
                {
                    await HiddenBottomBorder.LayoutTo(new Rectangle(BottomBorder.X, BottomBorder.Y, 0, BottomBorder.Height), 200);
                }
            };
        }
    }

We first set up the BindableProperties and public properties to enable the binding of the AccentColor, Text, Placeholder, and Keyboard. These BindableProperties also handle their own PropertyChanged events to update the view elements dynamically.

After that, we handle our constructor and wire up our Focused and Unfocused events on our BorderlessEntry. In the Focused event, we set the colors of the hidden bar, and the floating label to the accent color. We then start the animations of expanding the hidden bar, and the fade in and float up of the floating label.

On the Unfocused event, we do the inverse of setting the floating label color back to the unfocused color, check if there is text, if there is not – float the label back down, and then animate the collapse of the colored bar.

With all these things together, we get a nicely animated text field that has a floating label and expanding bottom bar with a given accent color!

ios_Material_Entry2

If you like what you see, don’t forget to follow me on twitter @Suave_Pirate, check out my GitHub, and subscribe to my blog to learn more mobile developer tips and tricks!

Interested in sponsoring developer content? Message @Suave_Pirate on twitter for details.

Xamarin.Tips – Super Simple Sqlite

Thinking about locally storing data and entity structures can be intimidating. You might have a complex data structure in your backend server structure and are trying to match that type of data in your mobile apps. Perhaps you’ve just never done it before and need a solution quickly. You might be over thinking it!

Let’s break it down into some straightforward steps.

  1. Create a Xamarin PCL or Shared project. It doesn’t matter if it’s Xamarin.Forms or native.
  2. Install this nuget package in your PCL or Shared project: https://www.nuget.org/packages/sqlite-net-pcl/
  3. Install the same nuget package in your Android, iOS, UWP, and any other project.
  4. Create your model in your PCL or Shared project. In this case, we will use a basic example model:
    public class Profile
    {
        public string Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Handle { get; set; }
        public DateTime CreatedDate { get; set; }
    }
    
  5. Create a DbContext class in your PCL or Shared project:
    public class DbContext
    {
        public static string LocalFilePath; // Set this before creating from platform project
        public SQLiteAsyncConnection Database { get; }
        /// <summary>
        /// Initialized a new DbContext
        /// </summary>
        public DbContext()
        {
            Database = new SQLiteAsyncConnection(LocalFilePath + "localdb.db3");
        }
    
        /// <summary>
        /// Creates a table for a given type in sql lite
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public async Task<CreateTablesResult> CreateTableAsync<T>() where T : new()
        {
        return await Database.CreateTableAsync<T>();
        }
    
        /// <summary>
        /// Gets a table by it's type from the db.
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <returns></returns>
        public AsyncTableQuery<T> Set<T>() where T : new()
        {
            return Database.Table<T>();
        }
    }
    
  6. Create a GenericRepository Class:
    public class GenericSqliteRepository<T> : IGenericRepository<T> where T : new()
    {
        protected readonly DbContext _context;
        public GenericSqliteRepository(DbContext context)
        {
            _context = context;
        }
        public virtual async Task InitializeAsync()
        {
            await _context.CreateTableAsync<T>();
        }
        public virtual async Task AddAsync(T entity)
        {
            await _context.Database.InsertOrReplaceAsync(entity);
        }
        public virtual async Task AddRangeAsync(IEnumerable<T> entities)
        {
            await _context.Database.InsertAllAsync(entities);
        }
    
        public virtual async Task<T> FindAsync(Expression<Func<T, bool>> predicate)
        {
            return await _context.Set<T>().Where(predicate).FirstOrDefaultAsync();
        }
    
        public virtual async Task<IEnumerable<T>> GetAsync(Expression<Func<T, bool>> predicate)
        {
            return await _context.Set<T>().Where(predicate).ToListAsync();
        }
    
        public virtual async Task<IEnumerable<T>> GetAsync(int skip, int take)
        {
            return await _context.Set<T>().Skip(skip).Take(take).ToListAsync();
        }
    
        public virtual async Task<IEnumerable<T>> GetAsync(Expression<Func<T, bool>> predicate, int skip, int take)
        {
            return await _context.Set<T>().Where(predicate).Skip(skip).Take(take).ToListAsync();
        }
    
        public virtual async Task RemoveAsync(T entity)
        {
            await _context.Database.DeleteAsync(entity);
        }
    
        public virtual async Task UpdateAsync(T entity)
        {
            await _context.Database.UpdateAsync(entity);
        }
    }
    
  7. Create a ProfileRepository Class:
    public class ProfileRepository : GenericSqliteRepository<Post>
    {
        public ProfileRepository(DbContext context) : base(context)
        {
        }
    }
    
  8. Set your file path in your platform code:
    1. Android
      DbContext.LocalFilePath = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
      
    2. iOS
      var docFolder = Environment.GetFolderPath(Environment.SpecialFolder.Personal);
      string libFolder = Path.Combine(docFolder, "..", "Library", "Databases");
      
      if (!Directory.Exists(libFolder))
      {
          Directory.CreateDirectory(libFolder);
      }
      DbContext.LocalFilePath = libFolder;
      
  9. Use your repository in your shared code or platform code or wherever you want.
    var repo = new ProfileRepository(new DbContext());
    await repo.InitializeAsync();
    ...
    await repo.AddAsync(new Profile {...});
    ...
    var profiles = await repo.GetAsync(0, 10);
    ...
    var profile = await repo.FindAsync(p => p.Id == "foo");
    ...
    
  10. Start storing your things!

This is obviously a simple situation that doesn’t cover all needs, but it’s a place to start for complex data models. Build repositories for each of your types. Control your queries that are very specific in those model-specific repositories.

Look out for a follow up post about some patterns and tips to use for complex and large data sets!

Connecting to an Authorized SignalR Hub from a .NET Client

In a previous post, I talked about adding Access and Refresh tokens to your Web Application using OAuth Bearer Tokens. In this post, we are going to be using this same logic to authorize external clients from an external .NET client application such as Windows Store apps, Xamarin.iOS, Xamarin.Android, etc.

Assuming we have our access token (and refresh token) stored locally on our client, we can use it to authorize our requests to our SignalR Hub. Let’s put together a basic Hub:

[Authorize]
public class SimpleHub : Hub
{
    public string AuthorizedString()
    {
        return "You are successfully Authorized";
    }

}

This is obviously and extremely simple example, and we aren’t going to get into calling client methods from the server with our authorized user as I will be covering that in a later post.
Now that we have our server-side Hub, let’s put together a client-side manager to connect to this Hub and make our request to AuthorizedString()

public class SimpleHubManager
{
    private HubConnection _connection;
    private IHubProxy _proxy;
    public SimpleHubManager()
    {
        _connection = new HubConnection("http://YOUR_DOMAIN/"); //connect to SignalR on your server
        _connection.Headers.Add("Authorization", string.format("Bearer {0}", YOUR_ACCESS_TOKEN)); //THIS IS WHERE YOU ADD YOUR ACCESS TOKEN MENTIONED ABOVE
        _proxy = _connection.CreateHubProxy("SimpleHub"); //connect to Hub from above
    }

    public async Task<string> GetAuthorizedString()
    {
        await _connection.Start(); //start connection
        var authorizedString = await _proxy.Invoke<string>("AuthorizedString"); //Invoke server side method and return value
        return authorizedString;
    }
}

As long as the Access Token being used by the client has not expired and is added to the Authorization Http Header, then we will be able to bypass the [Authorization] on the server.
So now, from our client, if we call:

var manager = new SimpleHubManager();
var authString = await manager.GetAuthorizedString(); //"You are successfully Authorized"

We see our string is exactly what we expect.

Stay tuned for some more advanced SignalR work in the future!