Question

我使用了以下代码，但它无效。

using System;
using System.Threading.Tasks;

using Xamarin.Forms;

using XLabs.Platform.Device;
using XLabs.Platform.Services.Media;

namespace CalbrenEnterprises.Pages
{
    public class TestPage : ContentPage
    {
        private ImageSource imageSource;
        private IMediaPicker mediaPicker;
        private Image img;
        private string status;

        public TestPage()
        {
            this.Title = "Camera Test";


            NavigationPage.SetHasNavigationBar(this, false);


            img = new Image() { HeightRequest = 300, WidthRequest = 300, BackgroundColor = Color.FromHex("#D6D6D2"), Aspect = Aspect.AspectFit };


            var addPictureButton = new Button()
            {
                Text = "Select Picture",
                Command = new Command(async () => { await SelectPicture(); })
            };


            StackLayout stack = new StackLayout();
            stack.VerticalOptions = LayoutOptions.FillAndExpand;

            stack.Children.Add(new BoxView { Color = Color.Transparent, HeightRequest = 20 });
            stack.Children.Add(addPictureButton);
            stack.Children.Add(img);


            ScrollView scrollview = new ScrollView
            {
                Orientation = ScrollOrientation.Vertical,
                VerticalOptions = LayoutOptions.FillAndExpand,
                Content = stack

            };

            this.Content = new StackLayout
            {
                Children = { scrollview }
            };


        }


        private async Task SelectPicture()
        {

            mediaPicker = DependencyService.Get<IMediaPicker>();

            imageSource = null;

            try
            {
                var mediaFile = await mediaPicker.SelectPhotoAsync(new CameraMediaStorageOptions
                {
                    DefaultCamera = CameraDevice.Front,
                    MaxPixelDimension = 400
                });
                imageSource = ImageSource.FromStream(() => mediaFile.Source);
                img.Source = imageSource;
            }
            catch (System.Exception ex)
            {
                this.status = ex.Message;
            }
        }



    }
}

问题：

如何从画廊中选择照片并在Xamarin.forms中的PCL项目中从相机拍摄照片？

Answer 1

var device = Resolver.Resolve<IDevice>();
mediaPicker = DependencyService.Get<IMediaPicker>() ?? device.MediaPicker;
if (mediaPicker == null) throw new NullReferenceException("MediaPicker DependencyService.Get error");

try
{
    if (mediaPicker.IsCameraAvailable)
    {
        var options = new CameraMediaStorageOptions() {
            DefaultCamera = CameraDevice.Front,
            SaveMediaOnCapture = true,
            Directory = "YourAppName",
            Name = string.Format("YourAppName_{0}", DateTime.Now.ToString("yyMMddhhmmss")),
            MaxPixelDimension = 1024,
            PercentQuality = 85
        };

        var mediaFile = await mediaPicker.TakePhotoAsync(options);

        if (mediaFile != null && mediaFile.Source != null)
        {
            // do something with your photo
        }
    }
    else
    {
        Logger.Info("Camera not available");
    }
}
catch (TaskCanceledException) 
{
    Logger.Info("TakePhoto cancelled");
}
catch (Exception ex)
{
    Logger.Error(ex);
}

在Tamarin.forms中从厨房和相机拍照

1 个答案: