Monotouch - 带有 iPad 应用的 UIImagePickerController答案

【问题标题】：Monotouch - UIImagePickerController with an iPad AppMonotouch - 带有 iPad 应用的 UIImagePickerController
【发布时间】：2011-05-08 15:58:59
【问题描述】：

我有一个仅限 iPad 的应用程序，我试图让用户从他们的PhotoLibrary 中选择图像，据我所知，我必须在UIPopOverController 中使用UIImagePickerController。我尝试了许多不同的方法来做到这一点，但我可以得到任何工作。我看过很多代码 sn-ps，但我似乎无法让它们在 Monotouch 下工作。

有人能指出正确的方法吗？非常感谢。

【问题讨论】：

标签： ipad xamarin.ios uiimagepickercontroller uipopovercontroller

【解决方案1】：

我必须调用创建图像选择器的代码以及对从主线程中选择的图像做出反应的代码才能使其工作：

    partial void OnImport (UIButton s)
    {
        BeginInvokeOnMainThread(delegate
        {

            UIImagePickerController picker = new UIImagePickerController();
            picker.ContentSizeForViewInPopover = new System.Drawing.SizeF(320,480);

            UIPopoverController popover = new UIPopoverController(picker);

            picker.FinishedPickingImage += delegate(object sender, UIImagePickerImagePickedEventArgs e) 
            {       
                BeginInvokeOnMainThread(delegate
                {
                    UIImage image = (UIImage)info.ObjectForKey(new NSString("UIImagePickerControllerOriginalImage"));
                    picker.DismissModalViewControllerAnimated(true);
                    // do something with image
                });

            };

            picker.SourceType = UIImagePickerControllerSourceType.PhotoLibrary;     
            popover.PresentFromRect(s.Frame, this.View, UIPopoverArrowDirection.Left, true);                    
        });
    }

【讨论】：

【解决方案2】：

这是我在应用程序中使用的代码 - 这应该是您开始使用它的良好开端。

UIImagePickerController imagePicker;
UIPopoverController popOver;

void AttachImageBtnTouched(object sender, EventArgs e)
{
    if (popOver == null || popOver.ContentViewController == null)
    {
        imagePicker = new UIImagePickerController();
        popOver = new UIPopoverController(imagePicker);
        ImagePickerDelegate imgDel = new ImagePickerDelegate();
        imagePicker.Delegate = imgDel;
        imagePicker.SourceType = UIImagePickerControllerSourceType.PhotoLibrary;
    }
    if (popOver.PopoverVisible)
    {
        popOver.Dismiss(true);
        imagePicker.Dispose();
        popOver.Dispose();
        return;
    }
    else
    {
        popOver.PresentFromRect(btnAttachment.Frame, this.View, UIPopoverArrowDirection.Any, true);
    }
}

// The Delegate class looks something like

public class ImagePickerDelegate : UIImagePickerControllerDelegate
{
    public ImagePickerDelegate()
    {}

    public override void FinishedPickingMedia(UIImagePickerController picker, NSDictionary info)
    {
        UIImage image = (UIImage)info.ObjectForKey(new NSString("UIImagePickerControllerOriginalImage"));
        // do whatever else you'd like to with the image
    }
}

【讨论】：