/// <summary>
/// 计算并设置Scroll的偏移量
/// </summary>
/// <param name="offSetX">鼠标X轴移动的偏移量</param>
/// <param name="offSetY">鼠标Y轴移动的偏移量</param>
void ComputeScrollOffSet(double offSetX, double offSetY)
{
double FocusRectTop = (double)FocusRect.GetValue(Canvas.TopProperty);
double FocusRectLeft = (double)FocusRect.GetValue(Canvas.LeftProperty);
double ViewportHostTop = (double)ViewportHost.GetValue(Canvas.TopProperty);
double ViewportHostLeft = (double)ViewportHost.GetValue(Canvas.LeftProperty);
//msgBox.Text = "FocusRect.Height" + FocusRect.Height + " ViewportHost.Height" + ViewportHost.Height;
if (offSetY > 0 && (FocusRect.Height + 8) < ViewportHost.Height && (ViewportHostTop + ViewportHost.Height) > (FocusRectTop + FocusRect.Height)) //鼠标向下且未出ViewportHost区域时
{
imageScroll.ScrollToVerticalOffset(imageScroll.VerticalOffset + (offSetY / 2) * (Viewport.Height / (ViewportHost.Height - FocusRectTop - FocusRect.Height)));
}
if (offSetY < 0 && (FocusRect.Height + 8) < ViewportHost.Height && ViewportHostTop < FocusRectTop) //鼠标向上且未出ViewportHost区域时
{
imageScroll.ScrollToVerticalOffset(imageScroll.VerticalOffset + (offSetY / 2) * ((Viewport.Height / FocusRectTop)));
}
if (offSetX > 0 && (FocusRect.Width + 8) < ViewportHost.Width && (ViewportHostLeft + ViewportHost.Width) > (FocusRectLeft + FocusRect.Width)) //鼠标向右且未出ViewportHost区域时
{
imageScroll.ScrollToHorizontalOffset(imageScroll.HorizontalOffset + (offSetX / 2) * (Viewport.Width / (ViewportHost.Width - FocusRectLeft - FocusRect.Width)));
}
if (offSetX < 0 && (FocusRect.Width + 8) < ViewportHost.Width && ViewportHostLeft < FocusRectLeft) //鼠标向左且未出ViewportHost区域时
{
imageScroll.ScrollToHorizontalOffset(imageScroll.HorizontalOffset + (offSetX / 2) * ((Viewport.Width / FocusRectLeft)));
}
}
/// <summary>
/// 加载图片文件信息
/// </summary>
/// <param name="fileStream"></param>
public void LoadImageStream(FileStream fileStream, Slider zoomInOut)
{
double width = ViewportHost.Width, height = ViewportHost.Height;
//hack:获取相应的图片高宽信息
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.SetSource(fileStream);
zoomInOut.Maximum = bitmapImage.PixelWidth;
#region 用获取的图片高宽初始化Viewport,FocusRect区域和以slider
if (bitmapImage.PixelWidth < bitmapImage.PixelHeight) //当图片宽小于高时
{
if (bitmapImage.PixelWidth > width) //当图片宽度超过可视区域的宽度时
{
height = ((double)width / bitmapImage.PixelWidth) * bitmapImage.PixelHeight;
//zoomInOut.Value = (double)width / bitmapImage.PixelWidth;
}
else //未超过时则使用图片的高宽初始化显示区域
{
width = bitmapImage.PixelWidth;
height = bitmapImage.PixelHeight;
}
}
else//当图片高小于宽时
{
if (bitmapImage.PixelHeight > height)//当图片高度超过可视区域的高度时
{
width = ((double)height / bitmapImage.PixelHeight) * bitmapImage.PixelWidth;
//zoomInOut.Value = (double)height / bitmapImage.PixelHeight;
}
else//未超过时则使用图片的高宽初始化显示区域
{
width = bitmapImage.PixelWidth;
height = bitmapImage.PixelHeight;
}
}
Viewport.Width = zoomInOut.Value = width;
Viewport.Height = height;
Viewport.SetValue(Canvas.TopProperty, (double)ViewportHost.GetValue(Canvas.TopProperty) + (ViewportHost.Height - Viewport.Height) / 2);
Viewport.SetValue(Canvas.LeftProperty, (double)ViewportHost.GetValue(Canvas.LeftProperty) + (ViewportHost.Width - Viewport.Width) / 2);
FocusRect.Width = width >= 100 ? 100 : width;
FocusRect.Height = height >= 100 ? 100 : height;
FocusRect.SetValue(Canvas.TopProperty, (double)ViewportHost.GetValue(Canvas.TopProperty) + (ViewportHost.Height - FocusRect.Height) / 2);
FocusRect.SetValue(Canvas.LeftProperty, (double)ViewportHost.GetValue(Canvas.LeftProperty) + (ViewportHost.Width - FocusRect.Width) / 2);
zoomInOut.Minimum = 16;
zoomInOut.ValueChanged += new RoutedPropertyChangedEventHandler <double>(ViewportSlider_ValueChanged);
imageRatio = (double)bitmapImage.PixelHeight / bitmapImage.PixelWidth;
SetRectangles();
#endregion
selectedImage.SetSource(fileStream);
}
/// <summary>
/// 滑动条事件处理代码
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
public void ViewportSlider_ValueChanged(object sender, RoutedPropertyChangedEventArgs <double> e)
{
Slider ZoomInOut = sender as Slider;
if (ZoomInOut.Value >= ZoomInOut.Minimum && imageRatio * ZoomInOut.Value >= ZoomInOut.Minimum)
{
Viewport.Width = ZoomInOut.Value;
Viewport.Height = imageRatio * ZoomInOut.Value;
Viewport.SetValue(Canvas.TopProperty, (double)ViewportHost.GetValue(Canvas.TopProperty) + (ViewportHost.Width - Viewport.Height) / 2);
Viewport.SetValue(Canvas.LeftProperty, (double)ViewportHost.GetValue(Canvas.LeftProperty) + (ViewportHost.Width - Viewport.Width) / 2);
AssureFocusRectZoomInZone(ZoomInOut.Value, ZoomInOut.Minimum);
}
}
/// <summary>
/// 初始化相应元素信息
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
void FocusRectangle_Loaded(object sender, RoutedEventArgs e)
{
Viewport.MinHeight = Viewport.MinWidth = 16;
Viewport.SetValue(Canvas.TopProperty, (double)ViewportHost.GetValue(Canvas.TopProperty) + (ViewportHost.Height - Viewport.Height) / 2);
Viewport.SetValue(Canvas.LeftProperty, (double)ViewportHost.GetValue(Canvas.LeftProperty) + (ViewportHost.Width - Viewport.Width) / 2);
//初始设置FocusRect
FocusRect.Width = FocusRect.Height = 100;
FocusRect.MaxWidth = ViewportHost.Width;
FocusRect.MaxHeight = ViewportHost.Height;
FocusRect.MinHeight = FocusRect.MinWidth = 8;
FocusRect.SetValue(Canvas.TopProperty, (double)ViewportHost.GetValue(Canvas.TopProperty) + (ViewportHost.Height - FocusRect.Height) / 2);
FocusRect.SetValue(Canvas.LeftProperty, (double)ViewportHost.GetValue(Canvas.LeftProperty) + (ViewportHost.Width - FocusRect.Width) / 2);
#region 8个小正方形位置
//左上
SmallRect[0] = new Rectangle()
{
Name = "SmallRect0", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//上中间
SmallRect[4] = new Rectangle()
{
Name = "SmallRect4", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//右上
SmallRect[1] = new Rectangle()
{
Name = "SmallRect1", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//左下
SmallRect[2] = new Rectangle()
{
Name = "SmallRect2", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//下中间
SmallRect[5] = new Rectangle()
{
Name = "SmallRect5", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//右下
SmallRect[3] = new Rectangle()
{
Name = "SmallRect3", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//左中间
SmallRect[6] = new Rectangle()
{
Name = "SmallRect6", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
//右中间
SmallRect[7] = new Rectangle()
{
Name = "SmallRect7", Width = Square.Width, Height = Square.Height, Fill = new SolidColorBrush(color)
};
SetRectangles();
#endregion
#region 事件绑定
foreach (Rectangle smallRectangle in SmallRect)
{
smallRectangle.Fill = new SolidColorBrush(color);
smallRectangle.MouseMove += new MouseEventHandler(smallRectangle_MouseMove);
smallRectangle.MouseLeftButtonUp += new MouseButtonEventHandler(smallRectangle_MouseLeftButtonUp);
smallRectangle.MouseLeftButtonDown += new MouseButtonEventHandler(smallRectangle_MouseLeftButtonDown);
smallRectangle.MouseEnter += new MouseEventHandler(smallRectangle_MouseEnter);
LayoutRoot.Children.Add(smallRectangle);
}
FocusRect.MouseMove += new MouseEventHandler(FocusRect_MouseMove);
FocusRect.MouseLeftButtonDown += new MouseButtonEventHandler(FocusRect_MouseLeftButtonDown);
FocusRect.MouseLeftButtonUp += new MouseButtonEventHandler(FocusRect_MouseLeftButtonUp);
FocusRect.MouseEnter += new MouseEventHandler(FocusRect_MouseEnter);
FocusRect.MouseLeave += new MouseEventHandler(FocusRect_MouseLeave);
#endregion
}
/// <summary>
/// FocusRect是否在Viewport中，如不在，则确保其不超出Viewport区域
/// </summary>
/// <returns></returns>
bool AssureFocusRectMoveInZone(string elementName)
{
bool result = true;
//try
//{
double ViewPortTop = (double)Viewport.GetValue(Canvas.TopProperty);
double ViewPortLeft = (double)Viewport.GetValue(Canvas.LeftProperty);
double FocusRectTop = (double)FocusRect.GetValue(Canvas.TopProperty);
double FocusRectLeft = (double)FocusRect.GetValue(Canvas.LeftProperty);
if (Viewport.Height > ViewportHost.Height) //已使用放大功能,向上拖动
{
if (0 > FocusRectTop)
{
FocusRect.SetValue(Canvas.TopProperty, (double)ViewportHost.GetValue(Canvas.TopProperty) + 4);
result = false;
}
}
else
{
if (ViewPortTop > FocusRectTop)
{
FocusRect.SetValue(Canvas.TopProperty, ViewPortTop);
result = false;
}
}
if (Viewport.Width >= ViewportHost.Width) //已使用放大功能,向左拖动
{
if (0 > FocusRectLeft)
{
FocusRect.SetValue(Canvas.LeftProperty, (double)ViewportHost.GetValue(Canvas.LeftProperty) + 4);
result = false;
}
}
else
{
if (ViewPortLeft > FocusRectLeft)
{
FocusRect.SetValue(Canvas.LeftProperty, ViewPortLeft);
result = false;
}
}
if (Viewport.Width >= ViewportHost.Width) //已使用放大功能,向右拖动
{
if ((ViewportHost.Width) < (FocusRect.Width + FocusRectLeft))
{
if (elementName == "FocusRect")
{
FocusRect.SetValue(Canvas.LeftProperty, ViewportHost.Width - FocusRect.Width - 4);
}
else
{
FocusRect.Width = ViewportHost.Width - FocusRectLeft - 4;
}
result = false;
}
}
else
{
if ((Viewport.Width + ViewPortLeft) < (FocusRect.Width + FocusRectLeft))
{
if (elementName == "FocusRect")
{
FocusRect.SetValue(Canvas.LeftProperty, ViewPortLeft + Viewport.Width - FocusRect.Width);
}
else
{
FocusRect.Width = ViewPortLeft + Viewport.Width - FocusRectLeft;
}
result = false;
}
}
if (Viewport.Height > ViewportHost.Height) //已使用放大功能,向下拖动
{
if ((ViewportHost.Height) < (FocusRect.Height + FocusRectTop))
{
if (elementName == "FocusRect")
{
FocusRect.SetValue(Canvas.TopProperty, ViewportHost.Height - FocusRect.Height - 4);
}
else
{
FocusRect.Height = ViewportHost.Height - FocusRectTop - 4;
}
result = false;
}
}
else
{
if ((Viewport.Height + ViewPortTop) < (FocusRect.Height + FocusRectTop))
{
if (elementName == "FocusRect")
{
FocusRect.SetValue(Canvas.TopProperty, ViewPortTop + Viewport.Height - FocusRect.Height);
}
else
{
FocusRect.Height = ViewPortTop + Viewport.Height - FocusRectTop;
}
result = false;
}
}
//}
//catch
//{
// result = false;
//}
return(result);
}