ActivityIndicator in Xamarin.Forms - xamarin

Question

Currently I am working on a project in which I have to navigate from one page (page1) to another (page2). As page2 is taking a long time to load so I was thinking to use ActivityIndicator, but it is not effective at all.
Please give me complete code to resolve my problem.
Page(1)
//code for tapping a label and to navigate to page2
void onpage1tapped(Object sender,EventArgs args)
{ label1.Opacity=0.5;
Device.StartTimer(TimeSpan.FromMilliseconds(100),()=>{label1.Opacity=1;return false; })
This.Navigate.PushAsync(new Page2());
}
Page(2)
//constructor for page2
public page2
{ InitializeComponent();
ActivityIndicator indicator=new ActivityIndicator{HorizontalOptions=LayoutOptions.CenterAndExpand,Color=Color.Black,IsVisible=false};
StackLayout stk=new StackLayout();
stk.Children.Add(indicator);
//Enabling activityindicator
indicator.IsRunning=true;
indicator.IsVisible=true;
//Below long time taking task
Assembly assembly = GetType().GetTypeInfo().Assembly;
string resource = String.Format("ks.texts.BST.txt");
//string resource = "advjava.texts.insertion.txt";
using (Stream s = assembly.GetManifestResourceStream(resource))
{
using (StreamReader sr = new StreamReader(s))
{
string line;
while (null != (line = sr.ReadLine()))
{
Label l = new Label { Text = line, TextColor = Color.FromRgb(110, 139, 69), FontSize = Device.GetNamedSize(NamedSize.Medium, typeof(Label)) };
stk.Children.Add(l);
}
}
}
//Disabling Activity indicator as the long task is complete
indicator.IsVisible=false;
indicator.IsRunning=false;
}

Answer 1

Use Acr.XamForms.UserDialogs Package. Have a look at it.. Hope it helps
Here is a documentation on how to implement Acr.XamForms.UserDialogs..
Hope it helps

Answer 2

This is only a sample code, But it's logic is right and pretty good works for me. :)
var indicator = new ActivityIndicator() {
HorizontalOptions = LayoutOptions.CenterAndExpand
};
indicator.SetBinding(ActivityIndicator.IsVisibleProperty, "IsBusy", BindingMode.OneWay);
indicator.SetBinding(ActivityIndicator.IsRunningProperty, "IsBusy", BindingMode.OneWay);
var button = new Button() {
HorizontalOptions = LayoutOptions.Fill,
Text = "BUTTON"
};
button.Clicked += (sender, e) => IsBusy = !IsBusy;
var root = new StackLayout() {
HorizontalOptions = LayoutOptions.FillAndExpand,
VerticalOptions = LayoutOptions.FillAndExpand,
Children = {
button,
indicator
}
};
Content = root;
You can refer this Link, which give a clear note on Github by ChaseFlorell.
Working Sample : Github

Answer 3

The Issue is with how your code is being read. It'll finish, then execute, but if you utilize the Task.Run, you'll be able to run on separate threads and keep that activity indicator up and running to show that your page is loading and your machine is busy.
void onpage1tapped(Object sender,EventArgs args) {
activityIndicator.IsVisible= true;
Task.Run( () => {
label1.Opacity=0.5;
Device.StartTimer(TimeSpan.FromMilliseconds(100),()= {
label1.Opacity=1;returnfalse;
})
This.Navigate.PushAsync(new Page2());
});
}