Question

我有一个scrollview，我需要该滚动视图的完整内容的屏幕截图，我在stackoverflow上搜索并尝试了许多解决方案但是只提供了viewcontroller总高度的屏幕截图。例如，如果scrollview的高度为1096，Viewcontroller高度为532，则根据Viewcontroller高度截取内容我发现只有这个代码在stackoverflow上有用，它返回了scrollview的完整高度，但它清除了Viewcontroller中scrollview的内容。任何帮助如何保留scrollview的内容或任何更好的解决方案，以获取swift中的完整屏幕截图。谢谢你

<Style TargetType="ToggleButton" x:Key="BtnKey">
            <Style.Setters>
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="{x:Type ToggleButton}">
                            <ControlTemplate.Resources>
                                <Storyboard x:Key="StartAni">
                                    <DoubleAnimation
                                        Storyboard.TargetName="border2"
                                        Storyboard.TargetProperty="StrokeThickness" To="0" Duration="0:0:0.2"/>
                                    <ColorAnimation
                                        Storyboard.TargetName="border2"
                                        Storyboard.TargetProperty="(Shape.Stroke).(SolidColorBrush.Color)" 
                                        To="Red" Duration="0"/>
                                    <DoubleAnimation 
                                           Storyboard.TargetName="border3" 
                                           Storyboard.TargetProperty="StrokeThickness" 
                                           From="0.0" To="5.0" Duration="0"/>
                                </Storyboard>

                                <Storyboard x:Key="StopAni">
                                    <DoubleAnimation
                                       Storyboard.TargetName="border2"
                                       Storyboard.TargetProperty="StrokeThickness" To="5" Duration="0:0:2.5"/>
                                    <ColorAnimation
                                       Storyboard.TargetName="border2"
                                       Storyboard.TargetProperty="(Shape.Stroke).(SolidColorBrush.Color)" 
                                       To="LightGreen" Duration="0"/>
                                    <DoubleAnimation
                                       Storyboard.TargetName="border3"
                                       Storyboard.TargetProperty="StrokeThickness"
                                       From="5.0" To="0.0" Duration="0:0:0.2"/>
                                </Storyboard>

                            </ControlTemplate.Resources>
                            <Grid>
                                <Canvas>

                                    <Ellipse x:Name="border1" Width="100" Height="100" Stroke="Transparent"/>
                                    <Ellipse x:Name="border2" Width="90" Height="90" Stroke="Transparent"/>
                                    <Ellipse x:Name="border3" Width="50" Height="50" Stroke="Transparent"/>
                                </Canvas>
                                <ContentPresenter />
                            </Grid>
                            <ControlTemplate.Triggers>
                                <DataTrigger Binding="{Binding IsDone}" Value="false">
                                    <DataTrigger.EnterActions>
                                        <BeginStoryboard Storyboard="{StaticResource StartAni}">

                                        </BeginStoryboard>
                                    </DataTrigger.EnterActions>
                                </DataTrigger>
                                <DataTrigger Binding="{Binding IsDone}" Value="true">
                                        <DataTrigger.EnterActions>
                                        <BeginStoryboard Storyboard="{StaticResource StopAni}">

                                        </BeginStoryboard>
                                    </DataTrigger.EnterActions>
                                    </DataTrigger>
                            </ControlTemplate.Triggers>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style.Setters>
        </Style>

Answer 1

在我的指导下使用this，我认为您可以使用以下方式对任何视图进行快照：

func snapShot(view:UIView) -> UIImage
{
    UIGraphicsBeginImageContextWithOptions(view.bounds.size, true, 0)
    view.drawViewHierarchyInRect(view.bounds, afterScreenUpdates: true)
    let image = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    return image
}

虽然使用滚动视图，但这只会返回滚动视图框架中可见内容的图像，因此我们可以创建辅助函数：

func snapShotScrollView(scrollView:UIScrollView) -> UIImage
{
    let bounds = scrollView.bounds
    scrollView.bounds.size = scrollView.contentSize
    let image = snapShot(scrollView)
    scrollView.bounds = bounds
    return image
}

这将简要调整滚动视图对其内容大小的界限。

我不知道这段代码是多么高效，但这对我来说非常适合在快捷的游乐场玩。例如，运行此代码：

let scrollView = UIScrollView(frame:CGRect(x: 0.0, y: 0.0, width: 200.0, height: 200.0))
scrollView.backgroundColor = UIColor.whiteColor()
scrollView.contentSize = CGSize(width: 600.0, height: 600.0)
let blueView = UIView(frame: CGRect(x: 0.0, y: 0.0, width: 200.0, height: 200.0))
blueView.backgroundColor = UIColor.blueColor()

let redView = UIView(frame: CGRect(x: 200.0, y: 200.0, width: 400.0, height: 600.0))
redView.backgroundColor = UIColor.redColor()
scrollView.addSubview(blueView)
scrollView.addSubview(redView)
let image = snapShotScrollView(scrollView)

结果调用snapShot本身只返回一个蓝色方块。在快照之后，滚动视图是具有原始内容的原始大小。

截图时，滚动视图的内容清晰

1 个答案: