内存不足的 Coverflow

Question

我正在开发 Windows 8 Phone 应用程序。

我有一个问题，我在图像顶部加载带有文本的图像。它称为覆盖流功能。

我收到Out of memory exception

for (int j = 0; j < items.Count; j++)
            {
                for (int i = 0; i < items.Collection.Count; i++)
                {
                    Myobj obj = items[j].Collection[i];
                    if (obj.correct == 1)
                    {
                        coverflow.Add(new CoverFlow(items[j].Text, answer.TextTwo));
                    }
                }
            }

            CarouselList.ItemsSource = coverflow;

数据模板：

<DataTemplate x:Key="DataTemplate1">
            <Grid VerticalAlignment="Center" HorizontalAlignment="Center">
                <Grid.RowDefinitions>
                    <RowDefinition/>
                </Grid.RowDefinitions>
                <Border Grid.Row="0" Height="400" Width="400" CornerRadius="30,30,30,30">
                    <Border.Background>
                        <ImageBrush ImageSource="Images/sample.png" />
                    </Border.Background>
                </Border>
                <Grid Grid.Row="0" HorizontalAlignment="Center" VerticalAlignment="Top">
                    <TextBlock HorizontalAlignment="Center" 
                               VerticalAlignment="Center"
                               Margin="5,20,5,5"
                               Foreground="#000000"
                               Text="{Binding Title}"/>
                </Grid>
                <Grid Grid.Row="0" HorizontalAlignment="Center" VerticalAlignment="Bottom">
                <TextBlock HorizontalAlignment="Center" 
                               VerticalAlignment="Center"
                               Margin="5,5,5,20"
                               Foreground="#000000"
                               Text="{Binding SubTitle}"/>
                </Grid>
            </Grid>
        </DataTemplate>

这里有大约 300 多个项目依次显示：

像这样：

它根本不工作我试图减少 widht and height from 400 to 200 它工作但我希望图像大小为 400 以便看起来不错。

即使我的图像是 400*400，我如何才能避免这种内存不足

Answer 1

这真的是我的想法。好久没处理这个了。

1.给自己写一个函数，它会返回一堆项目

public List<Item> GetFirstItems()
{
    return items.Collection.Take(50);
}

public Item GetOtherItems(int skip)
{ 
     return items.Collection.Skip(skip).Take(25)
}

2.连接到SelectionChangedEvent 以供您控制

//keep this somewhere so you know where you are in the list
var currentBatch = 0;

private void SelectionChanged(sender object, ChangedEventArgs e)
{
     var position = e.CurrentItemIndex % 25;

     if(position > currentBatch)
     {
          currentBatch = position;
          var newItems = GetOtherItems(currentBatch * 25);

          //take the global list of items and modify it;
          //because we are moving right we only need the last 25 so we
          //can skip the first 25
          coverflow= coverflow.Skip(25);

          //add your new items
          coverflow.AddRange(newItems);
          CarouselList.ItemsSource = coverflow; // you will have to clear the source first
     }
     else if(position < currentBatch)
     {
          currentBatch = position;
          var newItems = GetOtherItems(currentBatch * 25);

          //take the global list of items and modify it;
          //because we are moving left we only need the first 25 so we
          //can take the first 25
          coverflow= coverflow.Take(25);

          //add your new items
          newItems.AddRange(coverflow);
          coverflow = newItems;
          CarouselList.ItemsSource = coverflow; // you will have to clear the source first
     }
}

您还需要注意的另一件事是记住哪个是当前项目并将其再次设置为当前项目。

这一切都是从我的脑海中写出来的，我不知道它是否适用于你的控件，但我希望它至少能对你有所帮助:)