1. Microsoft Consumer Channels and Central Marketing Group
4/26/2017
WRL
Sridhar Madhugiri, Software Design Engineer
Lukasz Chodorski, Software Design Engineer
Microsoft Corporation
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

2. Agenda WRL Overview WRL Classes Consuming WinRT Project template Demo
4/26/2017
Agenda
WRL Overview
WRL Classes
Consuming WinRT
Mentions these are not in order of importance. Hint of Windows on ARM, but don’t add it as a bullet.
Project template
Demo
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

3. WRL Overview

4. WRL Template based implementation Consume and Author WinRT objects
4/26/2017
WRL
Template based implementation
Consume and Author WinRT objects
Exception Free
Mentions these are not in order of importance. Hint of Windows on ARM, but don’t add it as a bullet.
Works at ABI level
Developed specifically for WinRT
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

5. Why use WRL Porting COM components to Metro No exceptions requirement
4/26/2017
Why use WRL
Porting COM components to Metro
No exceptions requirement
Interop with Com
Mentions these are not in order of importance. Hint of Windows on ARM, but don’t add it as a bullet.
No C++ extensions requirement
Fine grained control
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

6. WRL Classes

7. Winrt Concepts WinRT Object Delegate Event Misc Reference counted
Implements IInspectable
Instantiated through factory
WeakReference support
Delegate
Callback
Interface with method
Delegate instance is WinRT object
Event
Delegate used as Event callback
Server advertises events
Client creates delegate and registers it to receive events
Misc
Reference count management
Asynchronous operations

8. WRL Classes WinRT Object Delegate Event Misc RuntimeClass
InspectableClass
ActivatableClass
ActivationFactory
Delegate
Callback
Event
EventSource
Callback
Misc
ComPtr, WeakPtr
AsyncBase
And many more

9. Consuming WinRT

10. ComPtr, HString
ComPtr<IActivationFactory> activationFactory;
HRESULT hr = GetActivationFactory(
HString::MakeReference(RuntimeClass_Windows_Foundation_Uri).Get(),
&activationFactory );
// Error handling
ComPtr<IUriRuntimeClassFactory> uriActivationFactory;
hr = activationFactory.As(&uriActivationFactory);
ComPtr<IUriRuntimeClass> uri;
hr = uriActivationFactory->CreateUri(
HString::MakeReference(L"
&uri
Wrappers::HString domainName;
hr = uri->get_Domain(domainName.GetAddressOf());

11. Delegate Callback<ITimerElapsedHandler>(
ComPtr<IThreadPoolTimerStatics> timerFactory;   
HRESULT hr = GetActivationFactory(
Wrappers::HString::MakeReference(RuntimeClass_Windows_System_Threading_ThreadPoolTimer).Get(),
&timerFactory );
       // Error handling
TimeSpan delay;
delay.Duration = 200;
ComPtr<IThreadPoolTimer> timer;
hr = timerFactory->CreateTimer(
Callback<ITimerElapsedHandler>(
[](IThreadPoolTimer* timer) -> HRESULT {
              // Perform some action in separate thread
              return S_OK;
       }
).Get(), delay, &timer

12. WRL Project Template

13. Project template Available in Online template gallery
Select Online/Templates/C++/WRL Class Library in New project dialog
Does not work with Beta
Template generated files
Project file with correct settings
IDL file with one interface and one runtimeclass
Source files that implement the interface and runtime class
Broiler plate code to implement standard exports

14. Default WRL project
demo

15. Project files Project settings IDL Module.cpp WRLClassLibrary1.cpp
Preprocessor Define
WINAPI_FAMILY=WINAPI_PARTITION_APP
MIDL setting to generate WinMD
Custom build step for mdmerge
IDL
namespace
runtimeclass, interface
exclusiveto, activatable
Module.cpp
Broilerplate code
Wires exports to WRL activation infrastructure
WRLClassLibrary1.cpp
RuntimeClass
Template parameters - interfaces for Object
Implements- AddRef, Release, QI, GetIids
WeakReference support
InspectableClass
Implements – GetRuntimeclassName, GetTrustLevel
ActivatableClass
Associates default Activation factory with class
Wires factory to WRL activation infrastructure

16. Add method
demo

17. Add Method IDL CPP Add method to interface Implement method in class
__stdcall important

18. Add event
demo

19. Add Event IDL CPP Delegate definition – keyword delegate
MIDL creates an interface with method that matches delegate signature
Add eventadd and eventremove methods to interface
Name of both methods should be same
Fixed signature
CPP
EventSource templated on delegate interface as member of class
Add methods corresponding to eventadd and eventremove methods in interface
Delegate represented by its interface name
eventadd function has add_ prefix and eventremove has remove_ prefix
In the implementation of add/remove call Add/Remove on EventSource
Invoke event by calling InvokeAll on EventSource

20. Add non default constructor
demo

21. Add Custom Constructor
IDL
Define constructor factory interface
Add one or more constructor methods, exclusiveto attribute
Out/retval parameter type has to match type specified with exclusiveto
Specify factory interface as parameter to activatable attribute on runtimeclass
CPP
Implement RuntimeClassInitialize
Two phase construction
Default constructor cannot fail
Parameters same as the ones on constructor interface method
Add factory class
Template on Constructor interface
Implement constructor interface methods
MakeAndInitialize
instantiates class & calls RuntimeClassInitialize
Use ActivitableClassWithFactory
Similar to ActivitableClass

22. Conclusion Fairly easy to use Exceptions cannot cross ABI boundary
4/26/2017
Conclusion
Fairly easy to use
Exceptions cannot cross ABI boundary
Tedious
Mentions these are not in order of importance. Hint of Windows on ARM, but don’t add it as a bullet.
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

23. Microsoft Consumer Channels and Central Marketing Group
4/26/2017
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.
© 2012 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.