借花献佛 WP7 中图片查看 缩放

大家在WP7 中 展现图片是我想肯定很纠结于如何实现 类似 手机照片查看是  照片能自由缩放 拖动的功能。
在这里我就借 toolkit 的花 给大家share一个小技巧

在 sl toolkit for wp 中 有个东西叫做 gestrue

功能我就不描述了 大家自己去看toolkit

我们要用的就是它 .

我们可以在toolkit 里面的把这个页面翻出来看看


cs 代码一大堆 就不贴了

xaml 里面是

<Border x:Name="border" Width="300" Height="200" BorderBrush="{StaticResource PhoneForegroundBrush}" BorderThickness="4,16,4,4" Background="{StaticResource PhoneAccentBrush}" RenderTransformOrigin="0.5,0.5" Opacity=".5" CacheMode="BitmapCache">
                <Border.RenderTransform>
                    <CompositeTransform x:Name="transform"/>
                </Border.RenderTransform>
                <toolkit:GestureService.GestureListener>
                    <toolkit:GestureListener 
                        Tap="OnTap" Hold="OnHold"
                        DragStarted="OnDragStarted" DragDelta="OnDragDelta" DragCompleted="OnDragCompleted"
                        Flick="OnFlick"
                        PinchStarted="OnPinchStarted" PinchDelta="OnPinchDelta" PinchCompleted="OnPinchCompleted"/>
                </toolkit:GestureService.GestureListener>
            </Border>

我们可以注意到  作用的就是那个 toolkit:GestureListener


我们现在要做的就是 把弄到 img 里面去 ..

代码如下
xaml

<Image x:Name="_image"  RenderTransformOrigin="0.5,0.5">
            <Image.RenderTransform>
                <CompositeTransform x:Name="transform"/>
            </Image.RenderTransform>
            <toolkit:GestureService.GestureListener>
                <toolkit:GestureListener 
                        Tap="OnTap" Hold="OnHold"
                        DragStarted="OnDragStarted" DragDelta="OnDragDelta" DragCompleted="OnDragCompleted"
                        Flick="OnFlick"
                        PinchStarted="OnPinchStarted" PinchDelta="OnPinchDelta" PinchCompleted="OnPinchCompleted"/>
            </toolkit:GestureService.GestureListener>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.IO;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Media.Animation;

using System.Windows.Shapes;
using Microsoft.Phone.Controls;
using Microsoft.Xna.Framework.Media;

namespace Demo
{
    public partial class MainPage : PhoneApplicationPage
    {
        //SolidColorBrush greenBrush = new SolidColorBrush(Colors.Green);
        //SolidColorBrush redBrush = new SolidColorBrush(Colors.Red);
        //SolidColorBrush normalBrush;

        double initialAngle;
        double initialScale;

        Uri _imageURI;

        BitmapImage _bitMapImage = new BitmapImage();

        public MainPage()
        {
            InitializeComponent();
        }

        protected override void OnNavigatedTo(System.Windows.Navigation.NavigationEventArgs e)
        {
            _imageURI = new Uri("http://photo.fanfou.com/n0/02/5y/3p_215854.jpg");

            
            _bitMapImage.DownloadProgress += new EventHandler<DownloadProgressEventArgs>(bitMapImage_DownloadProgress);
            _bitMapImage.UriSource = _imageURI; ;
            _image.Source = _bitMapImage;
            _progressBar.Visibility = System.Windows.Visibility.Visible;
            _progressBar.IsIndeterminate = true;
            
            base.OnNavigatedTo(e);
        }

        void bitMapImage_DownloadProgress(object sender, DownloadProgressEventArgs e)
        {
            if (e.Progress == 100)
            {
               
                _progressBar.Visibility = System.Windows.Visibility.Collapsed;
                _progressBar.IsIndeterminate = false;
            }
            //throw new NotImplementedException();
        }


        private void OnTap(object sender, Microsoft.Phone.Controls.GestureEventArgs e)
        {
            transform.TranslateX = transform.TranslateY = 0;
        }

        private void OnDoubleTap(object sender, Microsoft.Phone.Controls.GestureEventArgs e)
        {
            transform.ScaleX = transform.ScaleY = 0;
        }

        private void OnHold(object sender, Microsoft.Phone.Controls.GestureEventArgs e)
        {
            transform.TranslateX = transform.TranslateY = 0;
            transform.ScaleX = transform.ScaleY = 0;
            transform.Rotation = 0;
        }

        private void OnDragStarted(object sender, DragStartedGestureEventArgs e)
        {
            //border.Background = greenBrush;
        }

        private void OnDragDelta(object sender, DragDeltaGestureEventArgs e)
        {
            transform.TranslateX += e.HorizontalChange;
            transform.TranslateY += e.VerticalChange;
        }

        private void OnDragCompleted(object sender, DragCompletedGestureEventArgs e)
        {
            //border.Background = normalBrush;
        }

        private void OnPinchStarted(object sender, PinchStartedGestureEventArgs e)
        {
            //border.Background = redBrush;

            initialAngle = transform.Rotation;
            initialScale = transform.ScaleX;
        }

        private void OnPinchDelta(object sender, PinchGestureEventArgs e)
        {
           
            transform.Rotation = initialAngle + e.TotalAngleDelta;
            transform.ScaleX = transform.ScaleY = initialScale * e.DistanceRatio;
        }

        private void OnPinchCompleted(object sender, PinchGestureEventArgs e)
        {
            // _image.Background = normalBrush;
        }

        private void OnFlick(object sender, FlickGestureEventArgs e)
        {
            //flickData.Text = string.Format("{0} Flick: Angle {1} Velocity {2},{3}",
            //    e.Direction, Math.Round(e.Angle), e.HorizontalVelocity, e.VerticalVelocity);
        }

        private void ApplicationBarIconButton_Click(object sender, EventArgs e)
        {
            MemoryStream fileStream = new MemoryStream();
            try
            {
                MediaLibrary library = new MediaLibrary();

                string lName = DateTime.Now.ToString("yyyyMMddhhmmss") + ".jpg";



                WriteableBitmap CaptureImage = new WriteableBitmap(_bitMapImage);

                // 将WriteableBitmap转换为JPEG流编码，并储存到独立存储里.


                Extensions.SaveJpeg(CaptureImage, fileStream, CaptureImage.PixelWidth, CaptureImage.PixelHeight, 0, 100);
                fileStream.Seek(0, SeekOrigin.Begin);
                fileStream.Seek(0, SeekOrigin.Current);

                //把图片加在WP7 手机的媒体库.
                Picture pic = library.SavePicture(lName, fileStream);
                fileStream.Close();
                MessageBox.Show("保存成功！", string.Empty, MessageBoxButton.OK);
            }
            catch
            {
                MessageBox.Show("保存失败", string.Empty, MessageBoxButton.OK);
            }
            finally
            {
                fileStream.Close();
            }


        }
    }
}

Demo下载：https://files.cnblogs.com/qq278360339/Demo.rar

 

转自：F-sea的bolg