Windows10正式版发布到现在,我利用零零碎碎的一些时间对UWP进行一些学习,也基于这门技术开发了一个第三方的简书App.
优酷视频:
http://v.youku.com/v_show/id_XMTM2MjU4MjI4NA==.html
缓存支持同步和异步的两种方式,分别实现了两个接口:
internal interface IStorage
{ void AddItem(string key, object value); void UpdateItem(string key, object value); bool ContainItem(string key); void FlushAll();
T GetItem<T>(string key) where T : class;
List<T> GetItems<T>(string key) where T : class; bool RemoveItem(string key); long GetSize();
}
interface IStorageAsync
{
Task AddItemAsync(string key, object value);
Task UpdateItemAsync(string key, object value);
Task<bool> ContainItemAsync(string key);
Task FlushAllAsync();
Task<T> GetItemAsync<T>(string key) where T : class;
Task<List<T>> GetItemsAsync<T>(string key) where T : class;
Task<bool> RemoveItemAsync(string key); long GetSize();
}
通过Key和Value的方式实现增减删改.
public async Task<WeiboResult> ShareTextAsync(string text)
{ if (text == null)
{ throw new ArgumentNullException(nameof(text));
} if (string.IsNullOrWhiteSpace(text))
{ throw new ArgumentException("Text could not be empty", nameof(text));
} if (!UserInfo.CheckUseable())
{ string authorizeCode = await this.GetAuthorizeCodeAsync(); await this.Authorize(authorizeCode);
}
Uri uri = new Uri("https://api.weibo.com/2/statuses/update.json");
Dictionary<string, string> pairs = new Dictionary<string, string>();
pairs.Add("access_token", UserInfo.Token);
pairs.Add("status", text);
HttpFormUrlEncodedContent content = new HttpFormUrlEncodedContent(pairs); using (HttpClient client = new HttpClient())
{
HttpResponseMessage response; try
{
response = await client.PostAsync(uri, content);
} catch (Exception ex)
{ throw new Exception("Network error", ex);
} return await response.Content.ReadAsJsonAsync<WeiboResult>();
}
}public async Task<WeiboResult> ShareImageAsync(byte[] image, string text)
{ if (image == null)
{ throw new ArgumentNullException(nameof(image));
} if (text == null)
{ throw new ArgumentNullException(nameof(text));
} if (string.IsNullOrWhiteSpace(text))
{ throw new ArgumentException("Text could not be empty", nameof(text));
} if (!UserInfo.CheckUseable())
{ string authorizeCode = await this.GetAuthorizeCodeAsync(); await this.Authorize(authorizeCode);
}
Uri uri = new Uri("https://upload.api.weibo.com/2/statuses/upload.json");
HttpBufferContent bufferContent = new HttpBufferContent(image.AsBuffer());
HttpMultipartFormDataContent content = new HttpMultipartFormDataContent();
content.Add(new HttpStringContent(UserInfo.Token), "access_token");
content.Add(new HttpStringContent(text), "status");
content.Add(bufferContent, "pic", "pic.jpg"); using (HttpClient client = new HttpClient())
{
HttpResponseMessage response; try
{
response = await client.PostAsync(uri, content);
} catch (Exception ex)
{ throw new Exception("Network error", ex);
} return await response.Content.ReadAsJsonAsync<WeiboResult>();
}
}
异步线程的处理我在上一篇《讲讲我在Windows10(uwp)开发中遇到的一些坑》已经说过了.这里说下贴一下异步Command的代码:
public class AsyncCommand : AsyncCommandBase
{ private readonly Func<Task> command; public AsyncCommand(Func<Task> command)
{ this.command = command;
} public override bool CanExecute(object parameter)
{ return true;
} public override Task ExecuteAsync(object parameter)
{ return command();
}
}
对于UWP的下拉刷新,我在博客园里看到了几种实现方式:
UWP的一种下拉刷新实现
只贴了一种,因为目前实现下拉刷新的方式都是ListView外部套一个ScrollViewer来实现,这种实现方式有个严重的问题就是:ListView内部也是有一个ScrollViewer,当滑动的时候,会出现ListView内部的ScrollViewer被压缩,这样直接导致了下拉刷新的失败.
我这里思考了另一种方式,就是对ListView内部的ScrollViewer进行操作.
<ScrollViewer Margin="0,0,0,-100" RenderTransformOrigin="0.5,0.5" x:Name="ScrollViewer" AutomationProperties.AccessibilityView="Raw" BringIntoViewOnFocusChange="{TemplateBinding ScrollViewer.BringIntoViewOnFocusChange}" HorizontalScrollMode="{TemplateBinding ScrollViewer.HorizontalScrollMode}" HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}" IsHorizontalRailEnabled="{TemplateBinding ScrollViewer.IsHorizontalRailEnabled}" IsHorizontalScrollChainingEnabled="{TemplateBinding ScrollViewer.IsHorizontalScrollChainingEnabled}" IsVerticalScrollChainingEnabled="{TemplateBinding ScrollViewer.IsVerticalScrollChainingEnabled}" IsVerticalRailEnabled="{TemplateBinding ScrollViewer.IsVerticalRailEnabled}" IsDeferredScrollingEnabled="{TemplateBinding ScrollViewer.IsDeferredScrollingEnabled}" TabNavigation="{TemplateBinding TabNavigation}" VerticalScrollBarVisibility="{TemplateBinding ScrollViewer.VerticalScrollBarVisibility}" VerticalScrollMode="{TemplateBinding ScrollViewer.VerticalScrollMode}" ZoomMode="{TemplateBinding ScrollViewer.ZoomMode}">
<ScrollViewer.RenderTransform>
<CompositeTransform TranslateY="-100" />
</ScrollViewer.RenderTransform>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Border Height="{TemplateBinding RefreshHeaderHeight}" x:Name="PullToRefreshIndicator" Background="Transparent">
<Grid HorizontalAlignment="Center">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="auto" />
<ColumnDefinition Width="auto" />
</Grid.ColumnDefinitions>
<Grid Width="40">
<Viewbox x:Name="Arrow" Height="15" VerticalAlignment="Top" Margin="0,4,0,0" RenderTransformOrigin="0.5,0.5">
<Viewbox.RenderTransform>
<CompositeTransform Rotation="180" />
</Viewbox.RenderTransform>
<Image Source="ms-appx:///Assets/arrow.png" Width="12" Height="12.9999"/>
<!--<Path
Width="12"
Height="12.9999"
Stretch="Fill"
Fill="{TemplateBinding ArrowColor}"
Data="M 20.4289,10.4376L 25,15.0087L 23.571,16.4376L 20.0291,12.8957L 20.0291,21.9999L 18.0083,21.9999L 18.0083,12.8583L 14.4289,16.4377L 13,15.0087L 17.5624,10.429L 19.0087,9" />-->
</Viewbox>
</Grid>
<TextBlock Grid.Column="1" x:Name="PullPart" Text="{TemplateBinding PullPartTemplate}"/>
<TextBlock Grid.Column="1" Visibility="Collapsed" x:Name="ReleasePart" Text="{TemplateBinding ReleasePartTemplate}"/>
</Grid>
</Border>
<ItemsPresenter FooterTransitions="{TemplateBinding FooterTransitions}" FooterTemplate="{TemplateBinding FooterTemplate}"
Footer="{TemplateBinding Footer}" HeaderTemplate="{TemplateBinding HeaderTemplate}" Header="{TemplateBinding Header}"
HeaderTransitions="{TemplateBinding HeaderTransitions}" Padding="{TemplateBinding Padding}" Grid.Row="1"/>
</Grid></ScrollViewer>
对内部的ScrollViewer的压缩进行操作,这样能够比较精准的获取用户的下拉.
同时我已经把这个代码封装成一个单独的控件,你可以从下面的链接获取到源码:
https://github.com/youngytj/uwp_PullToRefreshListview
使用方式只要在xaml里添加如下代码即可使用:
<local:PullToRefreshListView x:Name="lv"
PullPartTemplate="Pull" ReleasePartTemplate="Release"
RefreshContent="lv_RefreshContent" MoreContent="lv_MoreContent"/>
PullPartTemplate和ReleasePartTemplate分别是下拉和释放时候的文字.然后后面是更新和加载更多时候的事件.
MainPage里面通过ContentControl的来绑定内容
<ContentControl Content="{Binding CurrentViewModel}" ContentTemplate="{Binding Path=CurrentTemplate}"
HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch"/>
View和ViewModel的绑定放在了App.xaml
<Application.Resources>
<ResourceDictionary>
<vm:ViewModelLocator x:Key="Locator"/>
<DataTemplate x:Key="HomeViewModel">
<view:HomeView/>
</DataTemplate>
...</Application.Resources>
这里有个注意的地方就是View只是作为一个资源的方式存在,当MainPage中发生页面转换时,会将ViewModel的名字作为一个Key(所以类名必须是Key)来寻找View.
public static class DataTemplateSelector
{ public static DataTemplate GetTemplate(ViewModelBase param)
{
Type t = param.GetType(); if(!views.ContainsKey(t.Name))
{
views.Add(t.Name, App.Current.Resources[t.Name] as DataTemplate);
} return views[t.Name];
}
}
没有上传到市场,因为我这边网络一直上载不了包,如果网络环境好了以后再考虑上传,下面是Github的源码地址:
Github
并不是很看好微软这种实现跨平台.除了目前UWP这门技术的不成熟,包括很多的缺失,诸如异步线程的处理问题,缺少对移动端的滑动的支持(不像android一样可以从底层开始实现一个行云流水般的手势操作,还有就是ScrollViewer依然存在之前的问题.),还有就是对于微软的这种跨平台的方式,我支持这种看法--因为硬件设备和运行环境的不同带来的用户体验的不同,才是跨平台最大的障碍!这一障碍,不是任何一个“技术”或“技术提供商”可以解决的!.总体来说,因为是全新的平台,相应的开源组件比较少,上手还需要一些时间来熟悉这个平台,平台的不足之处也需要自己从无到有.
这个客户端其实还有很多不好的地方,比如对于异步线程启动关闭的控制不足,缺少log,缺少对于缓存的系统的管理,还有导航系统的不足,不同网络的环境下的客户端优化的问题.但是我认为仅仅作为一个研究学习的项目,已经足够了.如果你喜欢或者支持这样的项目,帮忙点个推荐吧.