Ensuring CollectionView Scrollbar is Always Visible on Android in MAUI
Environment
| Product | CollectionView for .NET MAUI |
| Version | 7.1.0 |
Description
Currently, the CollectionView's scrollbars are not visible by default on Android devices. I want to make the scrollbar always visible to enhance user experience.
This KB article also answers the following questions:
- How to enable the vertical scrollbar in the CollectionView on Android?
- How to customize the scrollbar appearance in a MAUI CollectionView on Android?
- How to use a custom drawable for the scrollbar thumb in an Android MAUI applications?
Solution
To make the CollectionView's scrollbar always visible on Android, follow these steps:
1. Create the Scrollbar Thumb Drawable
First, create a thumb drawable for the scrollbar in the Android project's Resources -> drawable folder. Name this file "scrollview_thumb.xml". Here is an example of how the XML content might look:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle" >
<corners android:radius="4dp" />
<solid android:color="@color/customColorScrollbar"/>
</shape>
Ensure that the build action of this file is set to MauiXaml.
2. Configure the ScrollView Handler
Access the native ScrollView through a mapper to the ScrollViewHandler and apply the necessary configurations to make the scrollbar visible:
Microsoft.Maui.Handlers.ScrollViewHandler.Mapper.AppendToMapping("MyCustom", (handler, view) => {
#if ANDROID
handler.PlatformView.VerticalScrollBarEnabled = true;
handler.PlatformView.ScrollBarStyle = Android.Views.ScrollbarStyles.OutsideOverlay;
handler.PlatformView.VerticalScrollbarThumbDrawable = AndroidX.AppCompat.Content.Res.AppCompatResources.GetDrawable(Microsoft.Maui.ApplicationModel.Platform.AppContext, Drawable.scrollview_thumb);
handler.PlatformView.ScrollbarFadingEnabled = false;
handler.PlatformView.ScrollBarSize = 20;
#endif
});
By setting VerticalScrollBarEnabled to true and specifying a custom drawable for the VerticalScrollbarThumbDrawable, the vertical scrollbar will always be visible on Android devices.