Joshua,
How’s the bridge work going? Is there any update yet?
Thanks,
I got derailed for a day last week. I’m working on finishing it today. Sorry about the delay.
Sweet, thanks for the info!
Sorry for being such a nag… but is there a real chance to get the bridge working soon? My postponed deadline comes in a week but I have to consider the windows store certification time as well.
Sorry about the delay. I’m making several last minute design changes. Mostly because I think passing Object types to/from Lua has design issues. Plus, having an object argument type doesn’t make it obvious what the legal types are when pushing in arrays/lists and tables/dictionaries. The more interesting case is what to do when an array of bytes is pushed in (something our network library does on our other platforms), which can be either pushed in as a Lua array of number or as a single Lua string.
The new design will be done by the end of tomorrow.
I’m sure that the better design worth waiting, I just don’t want to surpass my new deadline and that’s why I keep asking.
Thanks for the details.
I understand. I definitely want your app to make it by the end of this month (or preferably earlier) too. And if it’s any consolation to you, I’ve been working 60 hour weeks trying to get Corona for WP8 to where you and everyone else needs it to be to. It’s just a lot of work. :)
I can imagine and I appreciate your work, really.
Olaf,
The Native/Lua bridge is done. Hopefully you’ll get the newest version from David soon. (We had some server problems today and yesterday… so hopefully everything is smoothed out now.)
Our newest WP8 .NET class framework documentation won’t be uploaded to our website at the moment since we’re gearing up for another release. But that said, the zip file David will send you contains a help file documenting the newest APIs. Plus, our Visual Studio integration will show all of our newest classes and their documentation via intellisense which should help you out.
Below is a quick example on how to communicate between C# and Lua. It’ll exercise some of its capabilities, hopefully giving you an idea on how to use it.
Here is an example MainPage.cs C# code that you can use to hook into the Corona runtime environment, listen in to the Corona runtime’s lifecycle via its .NET events, add Lua style event listeners, and dispatch events to Lua (or even to other .NET event handlers) via a Lua like Runtime:dispatchEvent() call. This code receives and dispatches Corona events.
public partial class MainPage : PhoneApplicationPage { /// \<summary\>Construstor. Initializes member variables and the user interface.\</summary\> public MainPage() { // Initialize this page's components that were set up via the UI designer. InitializeComponent(); // Set up Corona to automatically start up when the control's Loaded event has been raised. // Note: By default, Corona will run the "main.lua" file in the "Assets\Corona" directory. // You can change the defaults via the CoronaPanel's AutoLaunchSettings property. fCoronaPanel.AutoLaunchEnabled = true; // Add Corona event handlers. fCoronaPanel.Runtime.Loaded += OnCoronaRuntimeLoaded; fCoronaPanel.Runtime.Terminating += OnCoronaRuntimeTerminating; // Set up the CoronaPanel control to render fullscreen via the DrawingSurfaceBackgroundGrid control. // This significantly improves the framerate and is the only means of achieving 60 FPS. fCoronaPanel.BackgroundRenderingEnabled = true; fDrawingSurfaceBackgroundGrid.SetBackgroundContentProvider(fCoronaPanel.BackgroundContentProvider); fDrawingSurfaceBackgroundGrid.SetBackgroundManipulationHandler(fCoronaPanel.BackgroundManipulationHandler); } /// \<summary\> /// Called when the CoronaRuntimeEnvironment has been loaded/created and just before it executes the "main.lua". /// \</summary\> /// \<param name="sender"\>Reference to the CoronaRuntime object that raised this event.\</param\> /// \<param name="e"\>Provides access to the CoronaRuntimeEnvironment object that was just created/loaded.\</param\> private void OnCoronaRuntimeLoaded(object sender, CoronaLabs.Corona.WinRT.CoronaRuntimeEventArgs e) { // Set up Corona to call OnCustomCoronaEventReceived() when an event named "customEvent" gets dispatched. var eventHandler = new CoronaLabs.Corona.WinRT.CoronaLuaEventHandler(OnCoronaCustomEventReceived); e.CoronaRuntimeEnvironment.AddEventListener("customEvent", eventHandler); // You can also hook into an existing Corona event if you want to. eventHandler = new CoronaLabs.Corona.WinRT.CoronaLuaEventHandler(OnCoronaEnterFrameEventReceived); e.CoronaRuntimeEnvironment.AddEventListener("enterFrame", eventHandler); } /// \<summary\>Called when the CoronaRuntimeEnvironment is about to be destroyed.\</summary\> /// \<param name="sender"\>Reference to the CoronaRuntime object that raised this event.\</param\> /// \<param name="e"\>Provides access to the CoronaRuntimeEnvironment involved in this event.\</param\> private void OnCoronaRuntimeTerminating(object sender, CoronaLabs.Corona.WinRT.CoronaRuntimeEventArgs e) { // This method gets called when backing out of the app or when the CoronaPanel control // has been unloade/removed from the application page. } /// \<summary\>Called when a Corona event named "customEvent" has been dispatched.\</summary\> /// \<param name="sender"\>The Corona runtime environment the event was dispatched from.\</param\> /// \<param name="e"\>Provides the event table's properties/fields.\</param\> private CoronaLabs.Corona.WinRT.ICoronaBoxedData OnCoronaCustomEventReceived( CoronaLabs.Corona.WinRT.CoronaRuntimeEnvironment sender, CoronaLabs.Corona.WinRT.CoronaLuaEventArgs e) { // Fetch the Corona event name. var coronaEventName = e.EventName; // Fetch the custom event's message field. var boxedMessage = e.Properties.Get("message") as CoronaLabs.Corona.WinRT.CoronaBoxedString; if (boxedMessage != null) { string myMessageFromLua = boxedMessage.ToUtf16String(); } // Return a string back to whoever dispatched this event. return CoronaLabs.Corona.WinRT.CoronaBoxedString.From("Hello from C#."); } /// \<summary\> /// \<para\>Called when Corona's "enterFrame" event hsa been dispatched by Corona.\</para\> /// \<para\>This is just an example. Not recommended since this might reduce framerate a bit.\</para\> /// \</summary\> private CoronaLabs.Corona.WinRT.ICoronaBoxedData OnCoronaEnterFrameEventReceived( CoronaLabs.Corona.WinRT.CoronaRuntimeEnvironment sender, CoronaLabs.Corona.WinRT.CoronaLuaEventArgs e) { // Create a custom Corona event named "dotNetEvent" and dispatch it. var eventProperties = CoronaLabs.Corona.WinRT.CoronaLuaEventProperties.CreateWithName("dotNetEvent"); eventProperties.Set("message", "This event came from my C#."); eventProperties.Set("isCool", true); eventProperties.Set("powerLevel", 9000); var result = sender.DispatchEvent(new CoronaLabs.Corona.WinRT.CoronaLuaEventArgs(eventProperties)); var boxedMessage = result.ReturnedValue as CoronaLabs.Corona.WinRT.CoronaBoxedString; if (boxedMessage != null) { var returnedMessage = boxedMessage.ToUtf16String(); } // Corona's "enterFrame" event ignores return values. So, just return null. return null; } }
And here is main.lua code that goes with the above code. It will receive and dispatch events to/from C#.
-- Called when an event named "dotNetEvent" has been dispatched from C#. local function onDotNetEventReceived(event) -- Let's send an event named "customEvent" back to C#. local myNewEvent = { name = "customEvent", message = "This event came from Lua.", } local result = Runtime:dispatchEvent(myNewEvent) print("The 'customEvent' handler returned " .. tostring(result)) -- We can return a value to the dispatcher if we want. return "Hello from Lua!" end Runtime:addEventListener("dotNetEvent", onDotNetEventReceived)
I hope this helps!
Joshua,
Thanks so much for this example, when I get the new CoronaCards version from David I test it out!
One noob question, correct me if I’m wrong:
To hook up a Corona button without using enterFrame listener in C# I should just call this from inside a button:
Runtime:dispatchEvent({name = "customEvent"})
and then in C# in a “customEvent” listener I should define a “dotNetEvent” (right now it’s defined only in an “enterFrame” listener):
var eventProperties = CoronaLabs.Corona.WinRT.CoronaLuaEventProperties.CreateWithName("dotNetEvent");
to receive back a “dotNetEvent” event in Lua?
OR
it’s not necessary to add a “dotNetEvent” listener Lua, nor to define an event in C# if I’just to call this from the button:
local result = Runtime:dispatchEvent({name = "customEvent")
and this will just return a value I need from “customEvent” listener in C#?
If your C# custom event listener is able to return a value immediately, then yes, I recommend that you return a value immediately. For example…
local result = Runtime:dispatchEvent({name="requestingSum", x=2, y=2})
private void OnCoronaRuntimeLoaded(object sender, CoronaRuntimeEventArgs e) { var handler = new CoronaLuaEventHandler(OnRequestingSum); e.CoronaRuntimeEnvironment.AddEventListener("requestingSum", handler); } private ICoronaBoxedData OnRequestingSum(CoronaRuntimeEnvironment sender, CoronaLuaEventArgs e) { double sum = 0; try { double x = ((CoronaBoxedNumber)e.Properties.Get("x")).Value; double y = ((CoronaBoxedNumber)e.Properties.Get("y")).Value; sum = x + y; } catch (Exception) {} return new CoronaBoxedNumber(sum); }
If you have to a non-blocking async fetch, then you’ll need to create a separate event to be dispatched by C# later. I hope what I said makes sense.
You can actually name the events whatever you want. You don’t have to use the names I used in the example above. For example, I think the following names might be good for IAP in your app…
For example, these might be some good IAP event names on the Lua side…
-
“requestingPurchasedProducts” – Return all products already purchased? (Not sure if you can do a blocking return.)
-
“requestingPurchaseX” – Attempt to purchase product X.
-
“requestingPurchaseY” – Attempt to purchase product Y.
And perhaps these might be some good event names on the C# side…
-
“receivedPurchaseXResult” – The result of purchasing product X
-
“receivedPurchaseYResult” – The result of purchasing product X
I don’t recommend that you hook into the “enterFrame” event in C# because that would likely hurt your framerate a bit. I was just trying to show an example that you can listen to any Runtime events; those that already exist in Corona and also the events that you can create and dispatch for yourself.
So probably for IAPs I’d have to dispatch events from C#.
I’ve just received the new bits from David so I’ll soon let you know how it works for me.
Thanks!
I’ve got one more tip to make things simpler for you. You don’t have to wrap your .NET method within a handler class like I shown above. For example, you can change the following…
var handler = new CoronaLuaEventHandler(OnRequestingSum); e.CoronaRuntimeEnvironment.AddEventListener("requestingSum", handler);
…to the below, which works just as well…
e.CoronaRuntimeEnvironment.AddEventListener("requestingSum", OnRequestingSum);Thanks, I’ll change that!
OK, I started testing the bridge and it’s working, yay! 
I can open url pages and I’m receiving events back in Lua.
I have a problem with screenshot sharing though. When I try to capture the screenshot using
WriteableBitmap save = new WriteableBitmap(480, 800); save.Render(this, null);
I get a black screen captured. What argument should I pass here instead of ‘this’ to capture CoronaCards view?
Tried fCoronaPanel but didn’t work for me neither.
Also - is there a way to make the CoronaCards view modal for a while?
So when I display a native popup, no clicks would go through?
Ahh… screencaptures on WP8 Direct3D apps is a challenge. Which is why we don’t support it yet.
I don’t think a WriteableBitmap can capture what is custom Direct3D rendered to a DrawingSurfaceBackgroundGrid. I think the WriteableBitmap class can only capture what was rendered to a XAML control. (ie: Rendering via a DrawingSurfaceBackgroundGrid does not actually render to XAML, but gives us access to the app’s main Direct3D context which the native XAML framework uses to render its content.)
That said, capturing via a WriteableBitmap will work if you disable the CoronaPanel’s rendering to the DrawingSurfaceBackgroundGrid, because then it renders to a XAML SurfaceControl’s texture instead, which can be captured. The only problem with this is that you can’t render at 60 FPS when it is in this mode. But luckily we’ve set up our CoronaPanel to support hot-swapping between DrawingSurfaceBackgroundGrid and DrawingSurface rendering.
The following code successfully captures on the screen by doing what I’ve mentioned above. I consider it a hack though, but it’s the quickest thing I could come up with. The only problem is that you have to wait until the 2nd/3rd frame for the capture to occur.
private CoronaLabs.Corona.WinRT.CoronaLuaEventHandler fEnterFrameEventHandler = null; private int fEnterFrameCount = 0; private void OnCoronaRuntimeLoaded(object sender,CoronaRuntimeEventArgs e) { e.CoronaRuntimeEnvironment.AddEventListener("requestingScreenshot", OnRequestingScreenshot); } private ICoronaBoxedData OnRequestingScreenshot( CoronaRuntimeEnvironment sender, CoronaLuaEventArgs e) { // Switch from fast background rendering to rendering within the CoronaPanel. // We do this background rendered content is not capturable via WriteableBitmap. fCoronaPanel.BackgroundRenderingEnabled = false; // Schedule to capture the screen on the next rendered frame. if (fEnterFrameEventHandler == null) { fEnterFrameEventHandler = new CoronaLuaEventHandler(OnEnterFrame); } fEnterFrameCount = 0; sender.AddEventListener("enterFrame", fEnterFrameEventHandler); return null; } private ICoronaBoxedData OnEnterFrame( CoronaRuntimeEnvironment sender, CoronaLuaEventArgs e) { // The first frame still belongs to the background. Wait for the 2nd frame. fEnterFrameCount++; if (fEnterFrameCount \< 2) { return null; } // Remove the "enterFrame" event listener. // We don't want to capture the screen on every rendered frame. :) sender.RemoveEventListener("enterFrame", fEnterFrameEventHandler); // Capture the contents of the CoronaPanel. var writeableBitmap = new System.Windows.Media.Imaging.WriteableBitmap( (int)fCoronaPanel.ActualWidth, (int)fCoronaPanel.ActualHeight); writeableBitmap.Render(fCoronaPanel, null); writeableBitmap.Invalidate(); // As a quick test, display the captured image within an image control onscreen. var imageControl = new System.Windows.Controls.Image(); imageControl.Source = writeableBitmap; imageControl.Margin = new Thickness(50); fCoronaPanel.Children.Add(imageControl); // Re-enable fast 60 FPS background rendering. fCoronaPanel.BackgroundRenderingEnabled = true; return null; }Hmm… you know what, the above is not working reliably for me. I can only get it to capture while running under the .NET debugger. It won’t work while running under the “Native” debugger… or when not debugging the app (ie: release mode).
I think we’re running into the following WP8 bug…
Where capturing a XAML control or screen’s content using WriteableBitmap while using a DrawingSurfaceBackgroundGrid becomes unreliable. I’ve ran into this issue before. I think the only reliable way of doing this is in C++ via Direct3D.
I hate to say this, but you might want to skip this feature for now. I don’t think we can implement this on our end by your due date.
Yes, I’ve just tried it and the app crashes: “First-chance exception at 0x770259A3 in TaskHost.exe: Microsoft C++ exception: _com_error at memory location 0x01CEF600.”
OK, I’ll share a text message then.
There’s another thing: is there a way to make fCoronaPanel modal for a while, so when I display a native popup no clicks would go through?
Are you saying the taps on the popup that is on top of Corona are getting dispatched to Lua?
Edit:
I just put a XAML WebBrowser control on top of the CoronaPanel. Corona is not getting any tap events when I tap on the WebBrowser. So, I’m not sure what the issue is. Or perhaps what you want is to completely block all taps/touches from reaching Corona, but still allow Corona to be visible and animating/rendering?
Maybe it’s because I’m using a Windows Phone Toolkit to generate a popup? I’m not sure.
But yes - my clicks are getting through so I need to block all taps from reaching Corona
while remaining it visible under the popup.
Is there a way to do this?
Hold on. I just figured out how to reproduce the issue you discovered. In fact, I’ve found a TODO comment in my touch handling code to resolve this very issue in the future. *Slaps-Forehead*
Okay. I’ll take care of this now.
Side Note: We’ve just updated/uploaded our WP8 class documentation now. You can find our Native/Lua bridge related classes via the link below for you quick reference…
http://docs.coronalabs.com/daily/native/wp8/html/html/N_CoronaLabs_Corona_WinRT.htm