我已经阅读了如何在 Android 中执行此操作,但我似乎找不到 Xamarin Android 等效于为 Layout 的 LeftMargin 和 TopMargin 设置动画。显然 Xamarin 有“动画”,但我无法在 Xamarin 中弄清楚我设置“newLeftMargin * interpolatedTime”的“applyTransformation”部分。
这是标准的 Android 参考: Android - 使用动画更改左边距
Animation a = new Animation();
//applyTransformation???? with "newLeftMargin * interpolatedTime"
a.Duration = 500;
MyThingy.StartAnimation(a);
感谢用户 Apineda提供答案。这是我最终编写的代码,以防有人需要。第一个构造函数从它们的当前状态动画边距,而不是仅仅从零开始。第二个构造函数要求您指定起始边距。
class LayoutMarginAnimation : Android.Views.Animations.Animation
{
private ViewGroup ViewToTransform;
private int LeftMargin_Destination;
private int TopMargin_Destination;
private int LeftMargin_Source;
private int TopMargin_Source;
/// <summary>
/// Animates a layout from it's current margins to specified margins
/// </summary>
/// <param name="a_viewToTransform">A view to transform.</param>
/// <param name="a_LeftMargin_Destination">A left margin destination.</param>
/// <param name="a_TopMargin_Destination">A top margin destination.</param>
public LayoutMarginAnimation(
ViewGroup a_viewToTransform,
int a_LeftMargin_Destination,
int a_TopMargin_Destination
)
{
this.ViewToTransform = a_viewToTransform;
this.LeftMargin_Destination = a_LeftMargin_Destination;
this.TopMargin_Destination = a_TopMargin_Destination;
this.LeftMargin_Source = (this.ViewToTransform.LayoutParameters as RelativeLayout.LayoutParams).LeftMargin;
this.TopMargin_Source = (this.ViewToTransform.LayoutParameters as RelativeLayout.LayoutParams).TopMargin;
}
/// <summary>
/// Animates a layout from specified margins to specified margins, regardless of what the margins are currently set to.
/// </summary>
/// <param name="a_viewToTransform">A view to transform.</param>
/// <param name="a_LeftMargin_Source">A left margin source.</param>
/// <param name="a_TopMargin_Source">A top margin source.</param>
/// <param name="a_LeftMargin_Destination">A left margin destination.</param>
/// <param name="a_TopMargin_Destination">A top margin destination.</param>
public LayoutMarginAnimation(
ViewGroup a_viewToTransform,
int a_LeftMargin_Source,
int a_TopMargin_Source,
int a_LeftMargin_Destination,
int a_TopMargin_Destination
)
{
this.ViewToTransform = a_viewToTransform;
this.LeftMargin_Destination = a_LeftMargin_Destination;
this.TopMargin_Destination = a_TopMargin_Destination;
this.LeftMargin_Source = a_LeftMargin_Source;
this.TopMargin_Source = a_TopMargin_Source;
}
protected override void ApplyTransformation(float interpolatedTime, Transformation t)
{
//Console.WriteLine("ApplyTransformation with interpolatedTime = " + interpolatedTime);
RelativeLayout.LayoutParams layoutParams = this.ViewToTransform.LayoutParameters as RelativeLayout.LayoutParams;
layoutParams.LeftMargin = this.LeftMargin_Source + (int)((this.LeftMargin_Destination - this.LeftMargin_Source) * interpolatedTime);
layoutParams.TopMargin = this.TopMargin_Source + (int)((this.TopMargin_Destination - this.TopMargin_Source) * interpolatedTime);
this.ViewToTransform.LayoutParameters = layoutParams;
}
}
以下是如何调用这两个构造函数。
// Animates a layout from it's current margins to specified margins
LayoutMarginAnimation animation = new LayoutMarginAnimation(this.DraggableSeedImageContainer, 1000, 1000);
// Animates a layout from specified margins to specified margins, regardless of what the margins are currently set to.
//LayoutMarginAnimation animation = new LayoutMarginAnimation(this.DraggableSeedImageContainer, 200, 200, 1000, 1000);
animation.Duration = 500;
this.DraggableSeedImageContainer.StartAnimation(animation);