Xamrin.Forms 条目单元格如何更改占位符的字体大小

Question

我在想是否可以更改 EntryCell 上占位符的字体大小而不更改 EntryCell 上文本的 fontSize？

是否可以更改占位符的字体大小而不更改文本的字体大小

 Code = new EntryCell { Label = "Code:*", Text = "", Keyboard = Keyboard.Default, Placeholder = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" };

Answer 1

很遗憾，没有。

表单中没有 API 可以更改占位符字体大小。相反，您可以创建自己的自定义控件来执行此操作，或使用自定义渲染器修改本机视图中的占位符。

Answer 2

这是 android 的自定义渲染器。我在这里修改 HintTextColor(placeholder)。您可以用类似的方式修改字体。

  using System;
using Xamarin.Forms.Platform.Android;
using Xamarin.Forms;
using communityhealth;
using Android.Graphics;
using communityhealth.Android;


[assembly: ExportRenderer (typeof (MyUsernameEntry), typeof (MyUsernameEntryRenderer))]
[assembly: ExportRenderer (typeof (MyPasswordEntry), typeof (MyPasswordEntryRenderer))]
[assembly: ExportRenderer (typeof (MyEntry), typeof (MyEntryRenderer))]

namespace communityhealth.Android
{
    public class MyEntryRenderer : EntryRenderer
    {
        protected override void OnElementChanged (ElementChangedEventArgs<Entry> e)
        {
            base.OnElementChanged (e);
            if (e.OldElement == null) {   // perform initial setup
                // lets get a reference to the native control
                var nativeEditText = (global::Android.Widget.EditText) Control;
                // do whatever you want to the textField here!
                nativeEditText.SetBackgroundColor(global::Android.Graphics.Color.Transparent);
                nativeEditText.SetTextColor(global::Android.Graphics.Color.White);
                Typeface font = Typeface.CreateFromAsset (Forms.Context.Assets, "Neris-Light.otf");
                nativeEditText.TextSize = 14f;
                nativeEditText.Typeface = font;
            }
        }
    }

    public class MyUsernameEntryRenderer : MyEntryRenderer
    {
        protected override void OnElementChanged (ElementChangedEventArgs<Entry> e)
        {
            base.OnElementChanged (e);

            if (e.OldElement == null) {
                // lets get a reference to the native control
                var nativeEditText = (global::Android.Widget.EditText) Control;
                nativeEditText.Hint = "Username";
                nativeEditText.SetHintTextColor (global::Android.Graphics.Color.White);
                nativeEditText.TextSize = 18f;
            }
        }
    }

    public class MyPasswordEntryRenderer : MyEntryRenderer
    {
        protected override void OnElementChanged (ElementChangedEventArgs<Entry> e)
        {
            base.OnElementChanged (e);

            if (e.OldElement == null) {
                // lets get a reference to the native control
                var nativeEditText = (global::Android.Widget.EditText) Control;
                nativeEditText.Hint = "Password";
                nativeEditText.SetHintTextColor (global::Android.Graphics.Color.White);
                nativeEditText.TextSize = 18f;
            }
        }
    }
}

Xamrin.Forms 条目单元格如何更改占位符的字体大小

Xamrin.Forms Entry Cell How to change font size for Placeholder

c#

portable-class-library

xamarin

xamarin.forms