/// <summary>
/// Initializes a new instance of the <see cref="DLToolkit.Forms.Controls.FlowListViewInternalCell"/> class.
/// </summary>
/// <param name="flowListViewRef">Flow list view reference.</param>
public FlowListViewInternalCell(WeakReference <FlowListView> flowListViewRef)
{
_flowListViewRef = flowListViewRef;
FlowListView flowListView = null;
flowListViewRef.TryGetTarget(out flowListView);
_useGridAsMainRoot = !flowListView.FlowUseAbsoluteLayoutInternally;
if (!_useGridAsMainRoot)
{
_rootLayout = new AbsoluteLayout()
{
Padding = 0d,
BackgroundColor = flowListView.FlowRowBackgroundColor,
};
View = _rootLayout;
}
else
{
_rootLayoutAuto = new Grid()
{
RowSpacing = 0d,
ColumnSpacing = 0d,
Padding = 0d,
BackgroundColor = flowListView.FlowRowBackgroundColor,
};
View = _rootLayoutAuto;
}
_flowColumnTemplate = flowListView.FlowColumnTemplate;
_desiredColumnCount = flowListView.DesiredColumnCount;
_flowColumnExpand = flowListView.FlowColumnExpand;
}
public FlowListViewInternalCell(FlowListView flowListView)
{
this.flowListView = flowListView;
root = new Grid() {
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand,
RowSpacing = 0f,
ColumnSpacing = 0f,
Padding = 0f,
RowDefinitions = new RowDefinitionCollection() {
new RowDefinition() { Height = GridLength.Auto }
},
ColumnDefinitions = new ColumnDefinitionCollection()
};
for (int i = 0; i < this.flowListView.FlowColumnsDefinitions.Count; i++)
{
root.ColumnDefinitions.Add(new ColumnDefinition() {
Width = new GridLength(1, GridUnitType.Star)
});
}
View = root;
}
protected override DataTemplate OnSelectTemplate(object item, BindableObject container)
{
if (item is FlowLoadingModel)
{
FlowListView flowListView = null;
if (_flowListViewRef.TryGetTarget(out flowListView))
{
return(flowListView.FlowLoadingTemplate);
}
}
else if (item is FlowEmptyModel)
{
FlowListView flowListView = null;
if (_flowListViewRef.TryGetTarget(out flowListView))
{
return(flowListView.FlowEmptyTemplate);
}
}
return(_defaultTemplate);
}
/// <summary>
/// Initializes a new instance of the <see cref="DLToolkit.Forms.Controls.FlowListViewInternalCell"/> class.
/// </summary>
/// <param name="flowListViewRef">Flow list view reference.</param>
public FlowListViewInternalCell(WeakReference <FlowListView> flowListViewRef)
{
this.flowListViewRef = flowListViewRef;
FlowListView flowListView = null;
flowListViewRef.TryGetTarget(out flowListView);
rootLayout = new AbsoluteLayout()
{
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand,
Padding = 0d,
BackgroundColor = flowListView.FlowRowBackgroundColor,
};
View = rootLayout;
flowColumnsTemplates = flowListView.FlowColumnsTemplates;
desiredColumnCount = flowListView.DesiredColumnCount;
flowAutoColumnCount = flowListView.FlowAutoColumnCount;
flowColumnExpand = flowListView.FlowColumnExpand;
}
async Task ExecuteTapGestureRecognizer(View view)
{
var flowCell = view as IFlowViewCell;
if (flowCell != null)
{
flowCell.OnTapped();
}
FlowListView flowListView = null;
_flowListViewRef.TryGetTarget(out flowListView);
if (flowListView != null)
{
int tapBackgroundEffectDelay = flowListView.FlowTappedBackgroundDelay;
try
{
if (tapBackgroundEffectDelay != 0)
{
view.BackgroundColor = flowListView.FlowTappedBackgroundColor;
}
flowListView.FlowPerformTap(view, view.BindingContext);
}
finally
{
if (tapBackgroundEffectDelay != 0)
{
await Task.Delay(tapBackgroundEffectDelay);
view.BackgroundColor = flowListView.FlowRowBackgroundColor;
}
}
}
}
private void UpdateData()
{
var container = BindingContext as IList;
if (container == null)
{
return;
}
var newDesiredColumnCount = 0;
FlowListView flowListView = null;
if (_flowListViewRef.TryGetTarget(out flowListView) && flowListView != null)
{
_flowColumnTemplate = flowListView.FlowColumnTemplate;
newDesiredColumnCount = flowListView.FlowDesiredColumnCount;
_flowColumnExpand = flowListView.FlowColumnExpand;
}
var flowGroupColumn = BindingContext as FlowGroupColumn;
if (flowGroupColumn != null)
{
newDesiredColumnCount = flowGroupColumn.ColumnCount;
}
// Getting view types from templates
var containerCount = container.Count;
IList <DataTemplate> templates = GetDataTemplates(container);
bool layoutChanged = false;
if (flowGroupColumn != null && flowGroupColumn.ForceInvalidateColumns)
{
layoutChanged = true;
flowGroupColumn.ForceInvalidateColumns = false;
}
else
{
layoutChanged = RowLayoutChanged(containerCount, templates, newDesiredColumnCount);
}
_desiredColumnCount = newDesiredColumnCount;
if (!layoutChanged) // REUSE VIEWS
{
if (_useGridAsMainRoot)
{
for (int i = 0; i < containerCount; i++)
{
SetBindingContextForView(_rootLayoutAuto.Children[i], container[i]);
}
}
else
{
for (int i = 0; i < containerCount; i++)
{
SetBindingContextForView(_rootLayout.Children[i], container[i]);
}
}
}
else // RECREATE COLUMNS
{
_currentColumnTemplates = new List <DataTemplate>(templates);
if (_useGridAsMainRoot)
{
if (_rootLayoutAuto.Children.Count > 0)
{
_rootLayoutAuto.Children.Clear();
}
var colDefs = new ColumnDefinitionCollection();
for (int i = 0; i < _desiredColumnCount; i++)
{
colDefs.Add(new ColumnDefinition()
{
Width = new GridLength(1d, GridUnitType.Star)
});
}
_rootLayoutAuto.ColumnDefinitions = colDefs;
for (int i = 0; i < containerCount; i++)
{
var view = templates[i].CreateContent() as View;
if (view == null)
{
throw new InvalidCastException("DataTemplate must return a View");
}
AddTapGestureToView(view);
SetBindingContextForView(view, container[i]);
if (containerCount == 0 || _desiredColumnCount == 0)
{
return;
}
AddViewToLayoutAutoHeightEnabled(view, containerCount, i);
}
}
else
{
if (_rootLayout.Children.Count > 0)
{
_rootLayout.Children.Clear();
}
for (int i = 0; i < containerCount; i++)
{
var view = templates[i].CreateContent() as View;
if (view == null)
{
throw new InvalidCastException("DataTemplate must return a View");
}
AddTapGestureToView(view);
SetBindingContextForView(view, container[i]);
if (containerCount == 0 || _desiredColumnCount == 0)
{
return;
}
AddViewToLayoutAutoHeightDisabled(view, containerCount, i);
}
}
}
}
/// <summary>
/// Used to avoid linking issues
/// eg. when using only XAML
/// </summary>
public static void Init()
{
#pragma warning disable 0219
var dummy = new FlowListView();
#pragma warning restore 0219
}
/// <summary>
/// Override this method to execute an action when the BindingContext changes.
/// </summary>
/// <remarks></remarks>
protected override void OnBindingContextChanged()
{
base.OnBindingContextChanged();
var container = BindingContext as IList;
if (container == null)
{
return;
}
FlowListView flowListView = null;
if (_flowListViewRef.TryGetTarget(out flowListView) && flowListView != null)
{
_flowColumnTemplate = flowListView.FlowColumnTemplate;
_desiredColumnCount = flowListView.DesiredColumnCount;
_flowColumnExpand = flowListView.FlowColumnExpand;
}
// Getting view types from templates
var containerCount = container.Count;
IList <DataTemplate> templates = GetDataTemplates(container);
bool layoutChanged = RowLayoutChanged(containerCount, templates);
if (!layoutChanged) // REUSE VIEWS
{
if (_useGridAsMainRoot)
{
for (int i = 0; i < containerCount; i++)
{
SetBindingContextForView(_rootLayoutAuto.Children[i], container[i]);
}
}
else
{
for (int i = 0; i < containerCount; i++)
{
SetBindingContextForView(_rootLayout.Children[i], container[i]);
}
}
}
else // RECREATE COLUMNS
{
if (_useGridAsMainRoot)
{
if (_rootLayoutAuto.Children.Count > 0)
{
_rootLayoutAuto.Children.Clear();
}
}
else
{
if (_rootLayout.Children.Count > 0)
{
_rootLayout.Children.Clear();
}
}
_currentColumnTemplates = new List <DataTemplate>(templates);
for (int i = 0; i < containerCount; i++)
{
var view = (View)templates[i].CreateContent();
view.GestureRecognizers.Add(new TapGestureRecognizer()
{
Command = new Command(async(obj) =>
{
await ExecuteTapGestureRecognizer(view);
})
});
SetBindingContextForView(view, container[i]);
AddViewToLayout(view, containerCount, i);
}
}
}
/// <summary>
/// Override this method to execute an action when the BindingContext changes.
/// </summary>
/// <remarks></remarks>
protected override void OnBindingContextChanged()
{
rootLayout.BindingContext = BindingContext;
base.OnBindingContextChanged();
var container = BindingContext as IList;
if (container == null)
{
return;
}
// Getting view types from templates
var containerCount = container.Count;
IList <Type> columnTypes = GetViewTypesFromTemplates(container);
bool layoutChanged = RowLayoutChanged(containerCount, columnTypes);
if (!layoutChanged) // REUSE VIEWS
{
for (int i = 0; i < containerCount; i++)
{
SetBindingContextForView(rootLayout.Children[i], container[i]);
}
}
else // RECREATE COLUMNS
{
if (rootLayout.Children.Count > 0)
{
rootLayout.Children.Clear();
}
for (int i = 0; i < containerCount; i++)
{
var view = (View)Activator.CreateInstance(columnTypes[i]);
view.BindingContext = container[i];
view.GestureRecognizers.Add(new TapGestureRecognizer()
{
Command = new Command(async(obj) => {
var flowCell = view as IFlowViewCell;
if (flowCell != null)
{
flowCell.OnTapped();
}
FlowListView flowListView = null;
flowListViewRef.TryGetTarget(out flowListView);
if (flowListView != null)
{
int tapBackgroundEffectDelay = flowListView.FlowTappedBackgroundDelay;
try
{
if (tapBackgroundEffectDelay != 0)
{
view.BackgroundColor = flowListView.FlowTappedBackgroundColor;
}
flowListView.FlowPerformTap(view.BindingContext);
}
finally
{
if (tapBackgroundEffectDelay != 0)
{
await Task.Delay(tapBackgroundEffectDelay);
view.BackgroundColor = Color.Transparent;
}
}
}
})
});
SetBindingContextForView(view, container[i]);
AddViewToLayout(view, containerCount, i);
}
}
}
/// <summary>
/// Used to avoid linking issues
/// eg. when using only XAML
/// </summary>
public static void Init()
{
#pragma warning disable 0219
var dummy = new FlowListView();
#pragma warning restore 0219
}