using System;
using System.Collections.Generic;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;
using System.IO;
#region Explanation of why this .NET3.0 app is using .NET2.0 Dlls
//For some very simple .NET niceties like being able to save a bitmap
//to a filename I have had to use the System.Drawing .NET 2.0 Dll
//
//While this looks possible using something like the following :
//
//RenderTargetBitmap rtb = new RenderTargetBitmap((int)img.width,
//(int)img, 0, 0, PixelFormats.Default);
//rtb.Render(this.inkCanv);
//BmpBitmapEncoder encoder = new BmpBitmapEncoder();
//encoder.Frames.Add(BitmapFrame.Create(rtb));
//encoder.Save(file);
//file.Close();
//
//For this to work I would have needed to used a .NET 3.0 CroppedBitmap
//within the RenderTargetBitmap.Render() method. And as CroppedBitmap
//doesnt inherit from Visual this is not possible.
//
//So if anyone knows how to do this better in .NET 3.0 I am all ears
#endregion
using System.Drawing;
using System.Drawing.Drawing2D;
//Josh Smith excellent DragCanvas
using WPF.JoshSmith.Controls;
namespace ImageCropper
{
/// <summary>
/// Provides a simple Image cropping facility for a WPF image element,
/// where the cropped area may be picked using a rubber band and moved
/// by dragging the rubber band around the image. There is also a popup
/// window from where the user may accept or reject the crop.
/// </summary>
public partial class UcImageCropper : System.Windows.Controls.UserControl
{
#region CropperStyle Dependancy property
/// <summary>
/// A DP for the Cropp Rectangle Style
/// </summary>
public Style CropperStyle
{
get { return (Style)GetValue(CropperStyleProperty); }
set { SetValue(CropperStyleProperty, value); }
}
/// <summary>
/// register the DP
/// </summary>
public static readonly DependencyProperty CropperStyleProperty =
DependencyProperty.Register(
"CropperStyle",
typeof(Style),
typeof(UcImageCropper),
new UIPropertyMetadata(null, new PropertyChangedCallback(OnCropperStyleChanged)));
/// <summary>
/// The callback that actually changes the Style if one was provided
/// </summary>
/// <param name="depObj">UcImageCropper</param>
/// <param name="e">The event args</param>
static void OnCropperStyleChanged(DependencyObject depObj, DependencyPropertyChangedEventArgs e)
{
Style s = e.NewValue as Style;
if (s != null)
{
UcImageCropper uc = (UcImageCropper)depObj;
uc.selectCanvForImg.CropperStyle = s;
}
}
#endregion
#region Instance fields
private string ImgUrl = "";
private BitmapImage bmpSource = null;
private SelectionCanvas selectCanvForImg = null;
private DragCanvas dragCanvasForImg = null;
private System.Windows.Controls.Image img = null;
private Shape rubberBand;
private double rubberBandLeft;
private double rubberBandTop;
private string tempFileName;
private ContextMenu cmSelectionCanvas;
private RoutedEventHandler cmSelectionCanvasRoutedEventHandler;
private ContextMenu cmDragCanvas;
private RoutedEventHandler cmDragCanvasRoutedEventHandler;
private string fixedTempName = "temp";
private long fixedTempIdx = 1;
private double zoomFactor=1.0;
#endregion
#region Ctor
public UcImageCropper()
{
InitializeComponent();
//this.Unloaded += new RoutedEventHandler(UcImageCropper_Unloaded);
selectCanvForImg = new SelectionCanvas();
selectCanvForImg.CropImage += new RoutedEventHandler(selectCanvForImg_CropImage);
dragCanvasForImg = new DragCanvas();
}
#endregion
#region Public properties
public string ImageUrl
{
get { return this.ImgUrl; }
set
{
zoomFactor = 1.0;
ImgUrl = value;
grdCroppedImage.Visibility = Visibility.Hidden;
createImageSource();
createSelectionCanvas();
//apply the default style if the user of this control didnt supply one
if (CropperStyle == null)
{
Style s = gridMain.TryFindResource("defaultCropperStyle") as Style;
if (s != null)
{
CropperStyle = s;
}
}
}
}
#endregion
#region Private methods
/// <summary>
/// Deletes all occurences of previous unused temp files from the
/// current temporary path
/// </summary>
/// <param name="tempPath">The temporary file path</param>
/// <param name="fixedTempName">The file name part to search for</param>
/// <param name="CurrentFixedTempIdx">The current temp file suffix</param>
public void CleanUp(string tempPath, string fixedTempName, long CurrentFixedTempIdx)
{
//clean up the single temporary file created
try
{
string filename = "";
for (int i = 0; i < CurrentFixedTempIdx; i++)
{
filename = tempPath + fixedTempName + i.ToString() + ".jpg";
File.Delete(filename);
}
}
catch (Exception)
{
}
}
/// <summary>
/// Popup form Cancel clicked, so created the SelectionCanvas to start again
/// </summary>
private void btnCancel_Click(object sender, RoutedEventArgs e)
{
grdCroppedImage.Visibility = Visibility.Hidden;
createSelectionCanvas();
}
/// <summary>
/// Popup form Confirm clicked, so save the file to their desired location
/// </summary>
private void btnConfirm_Click(object sender, RoutedEventArgs e)
{
ImageUrl = tempFileName;
grdCroppedImage.Visibility = Visibility.Hidden;
}
/// <summary>
/// creates the selection canvas, where user can draw
/// selection rectangle
/// </summary>
private void createSelectionCanvas()
{
createImageSource();
selectCanvForImg.Width = bmpSource.Width * zoomFactor;
selectCanvForImg.Height = bmpSource.Height * zoomFactor;
selectCanvForImg.Children.Clear();
selectCanvForImg.rubberBand = null;
selectCanvForImg.Children.Add(img);
svForImg.Width = selectCanvForImg.Width;
svForImg.Height = selectCanvForImg.Height;
svForImg.Content = selectCanvForImg;
createSelectionCanvasMenu();
}
/// <summary>
/// Creates the selection canvas context menu
/// </summary>
private void createSelectionCanvasMenu()
{
cmSelectionCanvas = new ContextMenu();
MenuItem miZoom25 = new MenuItem();
miZoom25.Header = "Zoom 25%";
miZoom25.Tag = "0.25";
MenuItem miZoom50 = new MenuItem();
miZoom50.Header = "Zoom 50%";
miZoom50.Tag = "0.5";
MenuItem miZoom100 = new MenuItem();
miZoom100.Header = "Zoom 100%";
miZoom100.Tag = "1.0";
cmSelectionCanvas.Items.Add(miZoom25);
cmSelectionCanvas.Items.Add(miZoom50);
cmSelectionCanvas.Items.Add(miZoom100);
cmSelectionCanvasRoutedEventHandler = new RoutedEventHandler(MenuSelectionCanvasOnClick);
cmSelectionCanvas.AddHandler(MenuItem.ClickEvent, cmSelectionCanvasRoutedEventHandler);
selectCanvForImg.ContextMenu = cmSelectionCanvas;
}
/// <summary>
/// Handles the selction canvas context menu. Which will zoom the
/// current image to either 25,50 or 100%
/// </summary>
private void MenuSelectionCanvasOnClick(object sender, RoutedEventArgs args)
{
MenuItem item = args.Source as MenuItem;
zoomFactor = double.Parse(item.Tag.ToString());
img.RenderTransform = new ScaleTransform(zoomFactor, zoomFactor, 0.5, 0.5);
selectCanvForImg.Width = bmpSource.Width * zoomFactor;
selectCanvForImg.Height = bmpSource.Height * zoomFactor;
svForImg.Width = selectCanvForImg.Width;
svForImg.Height = selectCanvForImg.Height;
}
/// <summary>
/// Creates the Image source for the current canvas
/// </summary>
private void createImageSource()
{
bmpSource = new BitmapImage(new Uri(ImgUrl));
img = new System.Windows.Controls.Image();
img.Source = bmpSource;
//if there was a Zoom Factor applied
img.RenderTransform = new ScaleTransform(zoomFactor, zoomFactor, 0.5, 0.5);
}
/// <summary>
/// creates the drag canvas, where user can drag the
/// selection rectangle
/// </summary>
private void createDragCanvas()
{
dragCanvasForImg.Width = bmpSource.Width * zoomFactor;
dragCanvasForImg.Height = bmpSource.Height * zoomFactor;
svForImg.Width = dragCanvasForImg.Width;
svForImg.Height = dragCanvasForImg.Height;
createImageSource();
createDragCanvasMenu();
selectCanvForImg.Children.Remove(rubberBand);
dragCanvasForImg.Children.Clear();
dragCanvasForImg.Children.Add(img);
dragCanvasForImg.Children.Add(rubberBand);
svForImg.Content = dragCanvasForImg;
}
/// <summary>
/// Creates the drag canvas context menu
/// </summary>
private void createDragCanvasMenu()
{
cmSelectionCanvas.RemoveHandler(MenuItem.ClickEvent, cmSelectionCanvasRoutedEventHandler);
selectCanvForImg.ContextMenu = null;
cmSelectionCanvas = null;
cmDragCanvas = new ContextMenu();
MenuItem miCancel = new MenuItem();
miCancel.Header = "Cancel";
MenuItem miSave = new MenuItem();
miSave.Header = "Save";
cmDragCanvas.Items.Add(miCancel);
cmDragCanvas.Items.Add(miSave);
cmDragCanvasRoutedEventHandler = new RoutedEventHandler(MenuDragCanvasOnClick);
cmDragCanvas.AddHandler(MenuItem.ClickEvent, cmDragCanvasRoutedEventHandler);
dragCanvasForImg.ContextMenu = cmDragCanvas;
}
/// <summary>
/// Handles the selction drag context menu. Which allows user to cancel or save
/// the current croped area
/// </summary>
private void MenuDragCanvasOnClick(object sender, RoutedEventArgs args)
{
MenuItem item = args.Source as MenuItem;
switch (item.Header.ToString())
{
case "Save":
SaveCroppedImage();
break;
case "Cancel":
createSelectionCanvas();
break;
default:
break;
}
}
/// <summary>
/// Raised by the <see cref="selectionCanvas">selectionCanvas</see>
/// when the new crop shape (rectangle) has been drawn. This event
/// then replaces the current selectionCanvas with a <see cref="DragCanvas">DragCanvas</see>
/// which can then be used to drag the crop area around within a Canvas
/// </summary>
private void selectCanvForImg_CropImage(object sender, RoutedEventArgs e)
{
rubberBand = (Shape)selectCanvForImg.Children[1];
createDragCanvas();
}
/// <summary>
/// User cancelled out of the popup, so go back to showing original image
/// </summary>
private void lblExit_MouseDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
{
grdCroppedImage.Visibility = Visibility.Hidden;
createSelectionCanvas();
}
/// <summary>
/// Saves the cropped image area to a temp file, and shows a confirmation
/// popup from where the user may accept or reject the cropped image.
/// If they accept the new cropped image will be used as the new image source
/// for the current canvas, if they reject the crop, the existing image will
/// be used for the current canvas
/// </summary>
private void SaveCroppedImage()
{
if (popUpImage.Source!=null)
popUpImage.Source = null;
try
{
rubberBandLeft = Canvas.GetLeft(rubberBand);
rubberBandTop = Canvas.GetTop(rubberBand);
//create a new .NET 2.0 bitmap (which allowing saving) based on the bound bitmap url
using (System.Drawing.Bitmap source = new System.Drawing.Bitmap(ImgUrl))
{
//create a new .NET 2.0 bitmap (which allowing saving) to store cropped image in, should be
//same size as rubberBand element which is the size of the area of the original image we want to keep
using (System.Drawing.Bitmap target = new System.Drawing.Bitmap((int)rubberBand.Width, (int)rubberBand.Height))
{
//create a new destination rectange
System.Drawing.RectangleF recDest = new System.Drawing.RectangleF(0.0f, 0.0f, (float)target.Width, (float)target.Height);
//different resolution fix prior to cropping image
float hd = 1.0f / (target.HorizontalResolution / source.HorizontalResolution);
float vd = 1.0f / (target.VerticalResolution / source.VerticalResolution);
float hScale = 1.0f / (float)zoomFactor;
float vScale = 1.0f / (float)zoomFactor;
System.Drawing.RectangleF recSrc = new System.Drawing.RectangleF((hd * (float)rubberBandLeft) * hScale, (vd * (float)rubberBandTop) * vScale, (hd * (float)rubberBand.Width) * hScale, (vd * (float)rubberBand.Height) * vScale);
using (System.Drawing.Graphics gfx = System.Drawing.Graphics.FromImage(target))
{
gfx.DrawImage(source, recDest, recSrc, System.Drawing.GraphicsUnit.Pixel);
}
//create a new temporary file, and delete all old ones prior to this new temp file
//This is is a hack that I had to put in, due to GDI+ holding on to previous
//file handles used by the Bitmap.Save() method the last time this method was run.
//This is a well known issue see http://support.microsoft.com/?id=814675 for example
tempFileName = System.IO.Path.GetTempPath();
if (fixedTempIdx > 2)
fixedTempIdx = 0;
else
++fixedTempIdx;
//do the clean
CleanUp(tempFileName, fixedTempName, fixedTempIdx);
//Due to the so problem above, which believe you me I have tried and tried to resolve
//I have tried the following to fix this, incase anyone wants to try it
//1. Tried reading the image as a strea of bytes into a new bitmap image
//2. I have tried to use teh WPF BitmapImage.Create()
//3. I have used the trick where you use a 2nd Bitmap (GDI+) to be the newly saved
// image
//
//None of these worked so I was forced into using a few temp files, and pointing the
//cropped image to the last one, and makeing sure all others were deleted.
//Not ideal, so if anyone can fix it please this I would love to know. So let me know
tempFileName = tempFileName + fixedTempName + fixedTempIdx.ToString() + ".jpg";
target.Save(tempFileName, System.Drawing.Imaging.ImageFormat.Jpeg);
//rewire up context menu
cmDragCanvas.RemoveHandler(MenuItem.ClickEvent, cmDragCanvasRoutedEventHandler);
dragCanvasForImg.ContextMenu = null;
cmDragCanvas = null;
//create popup BitmapImage
BitmapImage bmpPopup = new BitmapImage(new Uri(tempFileName));
popUpImage.Source = bmpPopup;
grdCroppedImage.Visibility = Visibility.Visible;
}
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
#endregion
}
}
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