static void OnShowingPropertyChanging(BindableObject bindable, bool oldValue, bool newValue)
{
Device.BeginInvokeOnMainThread(delegate {
LoadingView mv = (LoadingView)bindable;
mv.indicator.IsRunning = newValue;
mv.IsVisible = newValue;
});
}
protected IncrementalPage()
{
RowsBeforeTheEndToLoad = 10;
LastSearch = string.Empty;
SearchCount = 0;
AllItems = new ObservableCollection <T>();
SearchBar = new SearchBar {
Placeholder = "Search for..."
};
SearchBar.TextChanged += (sender, args) => LoadSearch(SearchBar.Text);
LoadingView = new LoadingView {
IsVisible = false
};
LoadingView.SetBinding(LoadingView.IsShowingProperty,
new Binding("IsBusy", source: this));
ListView = new ListView(ListViewCachingStrategy.RecycleElement)
{
VerticalOptions = LayoutOptions.FillAndExpand,
SeparatorVisibility = SeparatorVisibility.Default,
HasUnevenRows = true,
ItemsSource = AllItems
};
ListView.ItemAppearing += (sender, e) => {
if (!IsLoading)
{
var foundIndex = AllItems.IndexOf(e.Item as T);
if (foundIndex == AllItems.Count - RowsBeforeTheEndToLoad)
{
LoadNextPage();
}
}
};
var layout = new RelativeLayout();
layout.Children.Add(
SearchBar,
Constraint.Constant(0),
Constraint.Constant(0),
Constraint.RelativeToParent(p => p.Width),
Constraint.Constant(50)
);
layout.Children.Add(
ListView,
Constraint.Constant(0),
Constraint.Constant(50),
Constraint.RelativeToParent(p => p.Width),
Constraint.RelativeToParent(p => p.Height - 50)
);
layout.Children.Add(
LoadingView,
Constraint.RelativeToParent(p => p.Width - 100),
Constraint.RelativeToParent(p => p.Height - 100),
Constraint.Constant(90),
Constraint.Constant(90)
);
Content = layout;
}