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using Android.Content;
using Android.Views;
using AView = Android.Views.View;
using Xamarin.Forms.Internals;
using System;
namespace Xamarin.Forms.Platform.Android
{
public class ViewCellRenderer : CellRenderer
{
protected override AView GetCellCore(Cell item, AView convertView, ViewGroup parent, Context context)
{
Performance.Start();
var cell = (ViewCell)item;
var container = convertView as ViewCellContainer;
if (container != null)
{
container.Update(cell);
Performance.Stop();
return container;
}
BindableProperty unevenRows = null, rowHeight = null;
if (ParentView is TableView)
{
unevenRows = TableView.HasUnevenRowsProperty;
rowHeight = TableView.RowHeightProperty;
}
else if (ParentView is ListView)
{
unevenRows = ListView.HasUnevenRowsProperty;
rowHeight = ListView.RowHeightProperty;
}
if (cell.View == null)
throw new InvalidOperationException($"ViewCell must have a {nameof(cell.View)}");
IVisualElementRenderer view = Platform.CreateRenderer(cell.View);
Platform.SetRenderer(cell.View, view);
cell.View.IsPlatformEnabled = true;
var c = new ViewCellContainer(context, view, cell, ParentView, unevenRows, rowHeight);
Performance.Stop();
return c;
}
internal class ViewCellContainer : ViewGroup, INativeElementView
{
readonly View _parent;
readonly BindableProperty _rowHeight;
readonly BindableProperty _unevenRows;
IVisualElementRenderer _view;
ViewCell _viewCell;
public ViewCellContainer(Context context, IVisualElementRenderer view, ViewCell viewCell, View parent, BindableProperty unevenRows, BindableProperty rowHeight) : base(context)
{
_view = view;
_parent = parent;
_unevenRows = unevenRows;
_rowHeight = rowHeight;
_viewCell = viewCell;
AddView(view.View);
UpdateIsEnabled();
UpdateLongClickable();
}
protected bool ParentHasUnevenRows
{
get { return (bool)_parent.GetValue(_unevenRows); }
}
protected int ParentRowHeight
{
get { return (int)_parent.GetValue(_rowHeight); }
}
public Element Element
{
get { return _viewCell; }
}
public override bool OnInterceptTouchEvent(MotionEvent ev)
{
if (!Enabled)
return true;
return base.OnInterceptTouchEvent(ev);
}
public void Update(ViewCell cell)
{
Performance.Start();
var renderer = GetChildAt(0) as IVisualElementRenderer;
var viewHandlerType = Registrar.Registered.GetHandlerType(cell.View.GetType()) ?? typeof(Platform.DefaultRenderer);
if (renderer != null && renderer.GetType() == viewHandlerType)
{
Performance.Start("Reuse");
_viewCell = cell;
cell.View.DisableLayout = true;
foreach (VisualElement c in cell.View.Descendants())
c.DisableLayout = true;
Performance.Start("Reuse.SetElement");
renderer.SetElement(cell.View);
Performance.Stop("Reuse.SetElement");
Platform.SetRenderer(cell.View, _view);
cell.View.DisableLayout = false;
foreach (VisualElement c in cell.View.Descendants())
c.DisableLayout = false;
var viewAsLayout = cell.View as Layout;
if (viewAsLayout != null)
viewAsLayout.ForceLayout();
Invalidate();
Performance.Stop("Reuse");
Performance.Stop();
return;
}
RemoveView(_view.View);
Platform.SetRenderer(_viewCell.View, null);
_viewCell.View.IsPlatformEnabled = false;
_view.View.Dispose();
_viewCell = cell;
_view = Platform.CreateRenderer(_viewCell.View);
Platform.SetRenderer(_viewCell.View, _view);
AddView(_view.View);
UpdateIsEnabled();
UpdateLongClickable();
Performance.Stop();
}
public void UpdateIsEnabled()
{
Enabled = _viewCell.IsEnabled;
}
protected override void OnLayout(bool changed, int l, int t, int r, int b)
{
Performance.Start();
double width = Context.FromPixels(r - l);
double height = Context.FromPixels(b - t);
Performance.Start("Element.Layout");
Xamarin.Forms.Layout.LayoutChildIntoBoundingRegion(_view.Element, new Rectangle(0, 0, width, height));
Performance.Stop("Element.Layout");
_view.UpdateLayout();
Performance.Stop();
}
protected override void OnMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
Performance.Start();
int width = MeasureSpec.GetSize(widthMeasureSpec);
int height;
if (ParentHasUnevenRows)
{
SizeRequest measure = _view.Element.Measure(Context.FromPixels(width), double.PositiveInfinity, MeasureFlags.IncludeMargins);
height = (int)Context.ToPixels(_viewCell.Height > 0 ? _viewCell.Height : measure.Request.Height);
}
else
height = (int)Context.ToPixels(ParentRowHeight == -1 ? BaseCellView.DefaultMinHeight : ParentRowHeight);
SetMeasuredDimension(width, height);
Performance.Stop();
}
void UpdateLongClickable()
{
// In order for context menu long presses/clicks to work on ViewCells which have
// and Clickable content, we have to make the container view LongClickable
// If we don't have a context menu, we don't have to worry about it
_view.View.LongClickable = _viewCell.ContextActions.Count > 0;
}
}
}
}
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