Creating Xamarin.Forms view that shows paragraph where each sentence is clickable

问题

I have a requirement to create a view on Xamarin.Forms that displays an array of strings in a paragraph. Each sentence should be:
1. Free flowing one after the other on the same line
2. Clickable so that it can be navigated upon click

Also, it is desirable to have such a paragraph justify aligned.

Here is the envisioned wireframe of the requirement. I have highlighted each string with alternating colors to illustrate how the list of strings (sentences) must ingest into a free flowing paragraph

Since I am new to Xamarin and still learning the basics, I need some help in designing this view with appropriate views/controls.

回答1:

1. Free flowing one after the other on the same line
2. Clickable so that it can be navigated upon click

We could implement them by using Span. Labels expose a FormattedText property that allows the presentation of text with multiple fonts and colors in the same label .

in xaml

<StackLayout VerticalOptions="FillAndExpand" HorizontalOptions="FillAndExpand">
   <!-- Place new controls here -->
   <Label
         x:Name="label"
         VerticalTextAlignment="Center"
         HorizontalTextAlignment="Center"
         HorizontalOptions="Center"
         VerticalOptions="CenterAndExpand" />
</StackLayout>

in code behind

var formattedString = new FormattedString();

Span span1 = new Span() { Text = "Note that a Span can also respond to any gestures that are added to the span's GestureRecognizers collection .", BackgroundColor = Color.Red,FontSize=20};
span1.GestureRecognizers.Add(new TapGestureRecognizer {NumberOfTapsRequired=1, Command = new Command( ()=> {  // will been invoked when you click it , do some thing you want  } ) });

formattedString.Spans.Add(span1);

Span span2 = new Span() { Text = "Note that a Span can also respond to any gestures that are added to the span's GestureRecognizers collection .", BackgroundColor = Color.Gray, FontSize = 20};
span2.GestureRecognizers.Add(new TapGestureRecognizer { NumberOfTapsRequired = 1, Command = new Command(() => { // will been invoked when you click it , do some thing you want  }) });

formattedString.Spans.Add(span2);

Span span3 = new Span() { Text = "Note that a Span can also respond to any gestures that are added to the span's GestureRecognizers collection .", BackgroundColor = Color.Red, FontSize = 20};
span3.GestureRecognizers.Add(new TapGestureRecognizer { NumberOfTapsRequired = 1, Command = new Command(() => { // will been invoked when you click it , do some thing you want}) });

formattedString.Spans.Add(span3);

label.FormattedText = formattedString;

For more details about Span you could check this docs .

Also, it is desirable to have such a paragraph justify aligned.

We could use Custom Renderer .

Note : JustificationMode is only available after Android 8.0 .

in your android project

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

using Android.App;
using Android.Content;
using Android.OS;
using Android.Runtime;
using Android.Views;
using Android.Widget;

using Xamarin.Forms;
using Xamarin.Forms.Platform.Android;

using xxx.Droid;

[assembly:ExportRenderer( typeof(Xamarin.Forms.Label),typeof(MyLabelRenderer)) ]

namespace xxx.Droid
{
    public class MyLabelRenderer : LabelRenderer
    {
        public MyLabelRenderer(Context context) : base(context)
        {

        }

        protected override void OnElementChanged(ElementChangedEventArgs<Label> e)
        {
            base.OnElementChanged(e);

            if(Control!=null)
            {
                if (Android.OS.Build.VERSION.SdkInt >= Android.OS.BuildVersionCodes.O)
                {
                    Control.JustificationMode = Android.Text.JustificationMode.InterWord;
                }
            }

        }
    }
}

来源：https://stackoverflow.com/questions/59711815/creating-xamarin-forms-view-that-shows-paragraph-where-each-sentence-is-clickabl