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GoBackAsync Method

GoBackAsync

Summary

Navigates asynchronously the WebView to the previous page in the navigation history.

Signature

1
public void GoBackAsync()

Return Value

void

Declaring Type

cAlgo.API.WebView

Examples

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 using cAlgo.API;
 namespace cAlgo.Robots
 {
     [Robot(AccessRights = AccessRights.None)]
     public class WebViewOnChart : Robot
     {
         private WebView _webView;
         private TextBox _addressTextBox;
         private TextBox _scriptTextBox;
         private Button _executeScriptButton;
         protected override void OnStart()
         {
             var goBackButton = new Button
             {
                 Text = "←",
                 Margin = 3
             };
             goBackButton.Click += OnGoBackButtonClick;
             var goForwardButton = new Button
             {
                 Text = "→",
                 Margin = 3
             };
             goForwardButton.Click += OnGoForwardButtonClick;
             _addressTextBox = new TextBox
             {
                 Text = "https://ctrader.com/",
                 Margin = 3,
                 Width = 150,
                 MinWidth = 150,
                 MaxWidth = 150
             };
             var goButton = new Button
             {
                 Text = "→",
                 Margin = 3
             };
             goButton.Click += OnGoButtonClick;
             var reloadButton = new Button
             {
                 Text = "Reload",
                 Margin = 3
             };
             reloadButton.Click += OnReloadButtonClick;
             var stopButton = new Button
             {
                 Text = "x",
                 Margin = 3
             };
             stopButton.Click += OnStopButtonClick;
             _scriptTextBox = new TextBox
             {
                 Text = "alert('Hi');",
                 Margin = 3,
                 Width = 150,
                 MinWidth = 150,
                 MaxWidth = 150,
                 IsEnabled = false
             };
             _executeScriptButton = new Button
             {
                 Text = "Execute Script",
                 Margin = 3,
                 IsEnabled = false
             };
             _executeScriptButton.Click += OnExecuteScriptButtonClick;
             var addressBarPanel = new StackPanel
             {
                 MaxHeight = 50,
                 VerticalAlignment = VerticalAlignment.Top,
                 BackgroundColor = Color.Black,
                 Orientation = Orientation.Horizontal
             };
             addressBarPanel.AddChild(goBackButton);
             addressBarPanel.AddChild(goForwardButton);
             addressBarPanel.AddChild(_addressTextBox);
             addressBarPanel.AddChild(goButton);
             addressBarPanel.AddChild(reloadButton);
             addressBarPanel.AddChild(stopButton);
             addressBarPanel.AddChild(_scriptTextbox);
             addressBarPanel.AddChild(_executeScriptButton);
             _webView = new WebView
             {
                 DefaultBackgroundColor = Color.Red
             };
             _webView.NavigationCompleted += OnWebViewNavigationCompleted;
             _webView.WebMessageReceived += OnWebViewWebMessageReceived;
             _webView.Loaded += OnWebViewLoaded;
             _webView.Unloaded += OnWebViewUnloaded;
             var mainGrid = new Grid(2, 1);
             mainGrid.Rows[0].SetHeightToAuto();
             mainGrid.Rows[1].SetHeightInStars(1);
             mainGrid.AddChild(addressBarPanel, 0, 0);
             mainGrid.AddChild(_webView, 1, 0);
             Chart.AddControl(mainGrid);
         }
         private void OnWebViewLoaded(WebViewLoadedEventArgs args)
         {
             Print($"Webview loaded, IsLoaded: {args.WebView.IsLoaded}");
             _webView.NavigateAsync(_addressTextBox.Text);
         }
         private void OnWebViewUnloaded(WebViewUnloadedEventArgs args)
         {
             Print($"Webview unloaded, IsLoaded: {args.WebView.IsLoaded}");
         }
         private void OnStopButtonClick(ButtonClickEventArgs args)
         {
             _webView.StopAsync();
         }
         private void OnExecuteScriptButtonClick(ButtonClickEventArgs args)
         {
             var result = _webView.ExecuteScript(_scriptTextBox.Text);
             Print($"IsSuccessful: {result.IsSuccessful} | Json: {result.Json}");
         }
         private void OnReloadButtonClick(ButtonClickEventArgs args)
         {
             _webView.ReloadAsync();
         }
         private void OnGoForwardButtonClick(ButtonClickEventArgs args)
         {
             _webView.GoForwardAsync();
         }
         private void OnGoBackButtonClick(ButtonClickEventArgs args)
         {
             _webView.GoBackAsync();
         }
         private void OnGoButtonClick(ButtonClickEventArgs args)
         {
             _webView.NavigateAsync(_addressTextBox.Text);
         }
         private void OnWebViewWebMessageReceived(WebViewWebMessageReceivedEventArgs args)
         {
             Print($"Source: {args.Source} | Message: {args.Message}");
         }
         private void OnWebViewNavigationCompleted(WebViewNavigationCompletedEventArgs args)
         {
             Print($"{args.HttpStatusCode} | {args.IsSuccessful} | {args.Url}");
             _addressTextBox.Text = args.Url;
             _scriptTextBox.IsEnabled = true;
             _executeScriptButton.IsEnabled = true;
         }
     }
 }
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 using cAlgo.API;
 namespace cAlgo.Robots
 {
     [Robot(AccessRights = AccessRights.None)]
     public class WebViewOnWindow : Robot
     {
         private WebView _webView;
         private TextBox _addressTextBox;
         private TextBox _scriptTextbox;
         private Button _executeScriptButton;
         protected override void OnStart()
         {
             var goBackButton = new Button
             {
                 Text = "←",
                 Margin = 3
             };
             goBackButton.Click += OnGoBackButtonClick;
             var goForwardButton = new Button
             {
                 Text = "→",
                 Margin = 3
             };
             goForwardButton.Click += OnGoForwardButtonClick;
             _addressTextBox = new TextBox
             {
                 Text = "https://ctrader.com/",
                 Margin = 3,
                 Width = 150,
                 MinWidth = 150,
                 MaxWidth = 150
             };
             var goButton = new Button
             {
                 Text = "→",
                 Margin = 3
             };
             goButton.Click += OnGoButtonClick;
             var reloadButton = new Button
             {
                 Text = "Reload",
                 Margin = 3
             };
             reloadButton.Click += OnReloadButtonClick;
             var stopButton = new Button
             {
                 Text = "x",
                 Margin = 3
             };
             stopButton.Click += OnStopButtonClick;
             _scriptTextbox = new TextBox
             {
                 Text = "alert('Hi');",
                 Margin = 3,
                 Width = 150,
                 MinWidth = 150,
                 MaxWidth = 150,
                 IsEnabled = false
             };
             _executeScriptButton = new Button
             {
                 Text = "Execute Script",
                 Margin = 3,
                 IsEnabled = false
             };
             _executeScriptButton.Click += OnExecuteScriptButtonClick;
             var addressBarPanel = new StackPanel
             {
                 MaxHeight = 50,
                 VerticalAlignment = VerticalAlignment.Top,
                 BackgroundColor = Color.Black,
                 Orientation = Orientation.Horizontal
             };
             addressBarPanel.AddChild(goBackButton);
             addressBarPanel.AddChild(goForwardButton);
             addressBarPanel.AddChild(_addressTextBox);
             addressBarPanel.AddChild(goButton);
             addressBarPanel.AddChild(reloadButton);
             addressBarPanel.AddChild(stopButton);
             addressBarPanel.AddChild(_scriptTextbox);
             addressBarPanel.AddChild(_executeScriptButton);
             _webView = new WebView
             {
                 DefaultBackgroundColor = Color.Red
             };
             _webView.NavigationCompleted += OnWebViewNavigationCompleted;
             _webView.WebMessageReceived += OnWebViewWebMessageReceived;
             _webView.Loaded += OnWebViewLoaded;
             _webView.Unloaded += OnWebViewUnloaded;
             var mainGrid = new Grid(2, 1);
             mainGrid.Rows[0].SetHeightToAuto();
             mainGrid.Rows[1].SetHeightInStars(1);
             mainGrid.AddChild(addressBarPanel, 0, 0);
             mainGrid.AddChild(_webView, 1, 0);
             var window = new Window
             {
                 Child = mainGrid
             };
             window.Show();
         }
         private void OnWebViewLoaded(WebViewLoadedEventArgs args)
         {
             Print($"Webview loaded, IsLoaded: {args.WebView.IsLoaded}");
             _webView.NavigateAsync(_addressTextBox.Text);
         }
         private void OnWebViewUnloaded(WebViewUnloadedEventArgs args)
         {
             Print($"Webview unloaded, IsLoaded: {args.WebView.IsLoaded}");
         }
         private void OnStopButtonClick(ButtonClickEventArgs args)
         {
             _webView.StopAsync();
         }
         private void OnExecuteScriptButtonClick(ButtonClickEventArgs args)
         {
             var result = _webView.ExecuteScript(_scriptTextbox.Text);
             Print($"IsSuccessful: {result.IsSuccessful} | Json: {result.Json}");
         }
         private void OnReloadButtonClick(ButtonClickEventArgs args)
         {
             _webView.ReloadAsync();
         }
         private void OnGoForwardButtonClick(ButtonClickEventArgs args)
         {
             _webView.GoForwardAsync();
         }
         private void OnGoBackButtonClick(ButtonClickEventArgs args)
         {
             _webView.GoBackAsync();
         }
         private void OnGoButtonClick(ButtonClickEventArgs args)
         {
             _webView.NavigateAsync(_addressTextBox.Text);
         }
         private void OnWebViewWebMessageReceived(WebViewWebMessageReceivedEventArgs args)
         {
             Print($"Source: {args.Source} | Message: {args.Message}");
         }
         private void OnWebViewNavigationCompleted(WebViewNavigationCompletedEventArgs args)
         {
             Print($"{args.HttpStatusCode} | {args.IsSuccessful} | {args.Url}");
             _addressTextBox.Text = args.Url;
             _scriptTextbox.IsEnabled = true;
             _executeScriptButton.IsEnabled = true;
         }
     }
 }

Last update: March 30, 2023