Xamarin Forms Android video (VideoView) black flash on page load or back key + looping

问题

I followed this guide/copied the sample from here for implementing a Video Player for both iOS and Android in Xamarin forms: https://docs.microsoft.com/en-us/xamarin/xamarin-forms/app-fundamentals/custom-renderer/video-player/

The videoplayer works but on page load it will shortly flash black. Also when going back it would shortly flash the videoplayer in front of the previous page.

You could try: videoView.setZOrderOnTop(true); but this gave me problems with other pages where the video would still be present even though it was not in the xaml.

回答1:

In order to fix this and integrate looping in Xamarin Forms (assuming you followed the guide above):

Add the code below to the end of the OnElementChanged() function

videoView.SetOnPreparedListener(new VideoLoop(videoView));

Create the videoloop class (I also wanted to loop)



using Android.Graphics;
using Android.Media;
using Android.Views;
using Android.Widget;
using YOURPROJECTHERE.Droid.FormsVideoLibrary;
using Java.Lang;
using System.Threading.Tasks;

namespace FormsVideoLibrary.Droid
{
    public class VideoLoop : Java.Lang.Object, Android.Media.MediaPlayer.IOnPreparedListener
    {
        VideoView Video;
        public VideoLoop(VideoView video)
        {
            Video = video;
            Video.SetBackgroundColor(Android.Graphics.Color.White);
        }

        public void OnPrepared(MediaPlayer mp)
        {
            mp.SetOnInfoListener(new OnInfo(Video));

            //Remove or comment the line below if you don't want to loop
            mp.Looping = true;
            mp.Start();
        }
    }
}

Now we make the background color transparent when the first frame is pushed (not at OnPrepared because it is still buffering at that point):

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

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

namespace YOURPOJECTNAMESPACE.Droid.FormsVideoLibrary
{
    class OnInfo : Java.Lang.Object, Android.Media.MediaPlayer.IOnInfoListener
    {
        VideoView Video;
        public OnInfo(VideoView video)
        {
            Video = video;
        }

        bool MediaPlayer.IOnInfoListener.OnInfo(MediaPlayer mp, MediaInfo what, int extra)
        {

            if (what == MediaInfo.VideoRenderingStart)
            {
                // video started; hide the placeholder.
                Video.SetBackgroundColor(Android.Graphics.Color.Transparent);
                return true;
            }
            return false;
        }
    }
}

I also added the below in the OnStopRequested function in the VideoRenderer class.

        void OnStopRequested(object sender, EventArgs args)
        {
            videoView.StopPlayback();
            videoView.SetBackgroundColor(Android.Graphics.Color.White);
        }

And then finally back in the forms common project xaml.cs add the below on each page with a video:

 protected override void OnAppearing()
        {
            xNAMEOFYOURVIDEO.Play();           
            xNAMEOFYOURVIDEO.Source = new ResourceVideoSource
                {
                    Path = "yourfile.mp4"
                };
        }

  protected override void OnDisappearing()
        {
            xNAMEOFYOURVIDEO.Stop();
        }

来源：https://stackoverflow.com/questions/60414907/xamarin-forms-android-video-videoview-black-flash-on-page-load-or-back-key-l

标签

xamarin.forms

android-videoview