C# Windows Phone 8.1:将远程映像添加到底部AppBar或AppBarButton

我想将远程图像添加到应用程序栏按钮。 我的图像就是这个url 我想从后端将它绑定到appbarbutton。我的后端代码是

propic.UriSource=newuri（“http://2.bp.blogspot.com/-yEbb9_qp-jg/U8-KGeZAy3I/AAAAAAAAB0U/m91Bv1jPAQI/s1600/india+赢+在+上议院.jpg“
但我的后端代码不工作…有人请告诉我怎么做

            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>

下面是我的Xaml代码

            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>

你不能给AppBar图像提供一个绝对的Uri，AppBarButtons就是不能这样工作

            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>

你可以下载你的图像，保存到本地存储，然后从那里以图像的形式读取。别忘了你的图像需要遵循大小调整格式

            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>

你可以在这里获得更多的信息

            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>


            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>

下面的代码将帮助您

            <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic" Height="100" Width="100"/>
                </AppBarButton.Icon>
            </AppBarButton>
            <CommandBar.SecondaryCommands>
                <AppBarButton Label="Ride Now">
                <AppBarButton.Icon>

                    <BitmapIcon x:Name="propic12" Height="100" Width="100"/>
                </AppBarButton.Icon>   
                </AppBarButton>
                <AppBarButton Label="x" Icon="Admin" />
                </CommandBar.SecondaryCommands>
        </CommandBar>
    </Page.BottomAppBar>

using (var htc = new HttpClient())
{
    var file = await htc.GetStreamAsync("Your image url");
    if (!isoStore.FileExists("shared/shellcontent/appbarimage.png"))
    {
        using (IsolatedStorageFileStream fileStream = isoStore.OpenFile("shared/shellcontent/appbarimage.png", FileMode.Create))
        {
            await file.CopyToAsync(fileStream);
        }
    }
}

propic.UriSource = new Uri("isostore:/Shared/ShellContent/appbarimage.png",UriKind.Relative);

它说isoStore在当前上下文中不存在，而IsolatedStorageFileStream在当前上下文中不存在……实际上，windows.storage.IsolatedStorage仅在windowsphone8.1中工作