【MediaElement】WPF视频播放器【1】

一、前言

      前两天上峰要求做一个软件使用向导，使用WPF制作。这不，这两天从一张白纸开始学起，做一个播放演示视频的使用向导。以下是粗设计的原型代码：

二、效果图

三、代码

       前台代码：

<Window
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:WPF_Nav"
xmlns:dxlc="http://schemas.devexpress.com/winfx/2008/xaml/layoutcontrol" xmlns:dxwui="http://schemas.devexpress.com/winfx/2008/xaml/windowsui" x:Class="WPF_Nav.MainWindow"
mc:Ignorable="d"
Title="MainWindow" Height="480" Width="900" WindowStyle="None">
<Grid Name="Main_Grid">
<Grid.RowDefinitions>
<RowDefinition Height="40"></RowDefinition>
<RowDefinition Height="343"></RowDefinition>
<RowDefinition Height="30"></RowDefinition>
<RowDefinition Height="50"></RowDefinition>
</Grid.RowDefinitions>
<Grid Name="Title" Grid.Row="0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"></ColumnDefinition>
<ColumnDefinition Width="500"></ColumnDefinition>
<ColumnDefinition Width="120"></ColumnDefinition>
<ColumnDefinition Width="80"></ColumnDefinition>
</Grid.ColumnDefinitions>
<Button Grid.Column="3" HorizontalAlignment="Center" Width="40" Height="40" Click="Button_Click" Margin="16,0,0,0" >关闭</Button>
</Grid>
<Grid Name="Movie" Grid.Row="1">
<MediaElement Stretch="Fill" LoadedBehavior="Manual" Name="QS_Movie" MediaOpened="Element_MediaOpened" Loaded="QS_Movie_Loaded" VerticalAlignment="Stretch" HorizontalAlignment="Stretch"></MediaElement>
<Button Name="LeftButton" Width="50" Height="50" HorizontalAlignment="Left" VerticalAlignment="Center" Click="Left_Click">上一个</Button>
<Button Name="RightButton" Width="50" Height="50" HorizontalAlignment="Right" VerticalAlignment="Center" Click="Right_Click">下一个</Button>
</Grid>
<Grid Name="Control_Progress" Grid.Row="2">
<Slider Height="30" Width="700" Name="timelineSlider" VerticalAlignment="Center"  PreviewMouseLeftButtonDown="timelineMDown"  PreviewMouseLeftButtonUp="timelineMUp" BorderThickness="0,5,0,0" ></Slider>
</Grid>
<Grid Name="Movie_Control" Grid.Row="3" Margin="0,0,0,0">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="200"></ColumnDefinition>
<ColumnDefinition Width="500"></ColumnDefinition>
<ColumnDefinition Width="50"></ColumnDefinition>
<ColumnDefinition Width="150"></ColumnDefinition>
</Grid.ColumnDefinitions>
<StackPanel Grid.Column="1" Orientation="Horizontal" HorizontalAlignment="Center">
<Button Height="40" Width="40" x:Name="Play" Click="Play_Click" Margin="20,0">播放</Button>
<Button Height="40" Width="40" x:Name="Pause" Click="Pause_Click" Margin="20,0">暂停</Button>
</StackPanel>
<Slider Height="25" Width="120" Name="Volunme" Minimum="0" Maximum="1" Value="{Binding ElementName=QS_Movie,Path=Volume,Mode=TwoWay}" Grid.Column="3" HorizontalAlignment="Left" Margin="0,5,0,0" ></Slider>
<Button Height="25" Width="40" Name="Horn" Grid.Column="2" HorizontalAlignment="Right" Margin="0,13">音量</Button>
</Grid>
</Grid>
</Window>

            后台代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
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.Navigation;
using System.Windows.Shapes;
using System.Windows.Threading;

namespace WPF_Nav
{
/// <summary>
/// MainWindow.xaml 的交互逻辑
/// </summary>
public partial class MainWindow : Window
{
DispatcherTimer dispatcherTimer = new System.Windows.Threading.DispatcherTimer(); // 定义一个DT
public MainWindow()
{
InitializeComponent();
}

private void Play_Click(object sender, RoutedEventArgs e)
{
QS_Movie.Play();
}

private void Pause_Click(object sender, RoutedEventArgs e)
{
QS_Movie.Pause();
}

private void Element_MediaOpened(object sender, EventArgs e)
{
timelineSlider.Maximum = QS_Movie.NaturalDuration.TimeSpan.TotalMilliseconds;  //设置slider最大值
int sec = (int)QS_Movie.NaturalDuration.TimeSpan.TotalSeconds;
dispatcherTimer.Tick += new EventHandler(dispatcherTimer_Tick); //超过计时间隔时发生
dispatcherTimer.Interval = new TimeSpan(0, 0, 0, 0, 500); //DT间隔
dispatcherTimer.Start(); //DT启动
}

private void dispatcherTimer_Tick(object sender, EventArgs e)
{
timelineSlider.Value = QS_Movie.Position.TotalMilliseconds; //slider滑动值随播放内容位置变化
}

private void timelineMDown(object sender, EventArgs e)
{
dispatcherTimer.Stop();
}
private void timelineMUp(object sender, EventArgs e)
{
QS_Movie.Position = new TimeSpan(0, 0, 0, 0, (int)timelineSlider.Value);
dispatcherTimer.Start();
QS_Movie.Play();
}

private void QS_Movie_Loaded(object sender, RoutedEventArgs e)
{
QS_Movie.Source = new Uri(@"E:\Test\WPFTest\Sources\preview.mp4");
QS_Movie.Play();
System.Threading.Thread.Sleep(500);
QS_Movie.Pause();
}

private void Left_Click(object sender, RoutedEventArgs e)
{
QS_Movie.Source = new Uri(@"E:\Test\WPFTest\Sources\preview1.mp4");
QS_Movie.Play();
System.Threading.Thread.Sleep(500);
QS_Movie.Pause();
}

private void Right_Click(object sender, RoutedEventArgs e)
{
QS_Movie.Source = new Uri(@"E:\Test\WPFTest\Sources\preview2.mp4");
QS_Movie.Play();
System.Threading.Thread.Sleep(500);
QS_Movie.Pause();
}

private void Button_Click(object sender, RoutedEventArgs e)
{
this.Close();
}

}

}

四、小结

刚玩WPF两天，可能有些地方写的不好望见谅，听江湖传言<MediaElement>可能对Win8不支持，我也不清楚，我是Win7的。所以以上代码仅供参考。

PS：使用向导该怎么做？因为公司软件里的按钮都能按F1直接切到官方文档，还有Tooltips自带小视频演示，我这使用向导思来想去还是用视频的方式呈现，但是组长说做的像个播放器，不像使用向导，我是想把软件每步操作都做成视频左右翻页的，确是是像播放器。这可怎么整？求万能的博友指明一条活路！