initial commit of the interop engine + new flutter module + fixes for…

… minor issues

this commit introduces the new experimental `interop` module, which is used to allow the use of `therecipe/qt` from languages other than go or javascript.
as a start, there was support for the dart language added (currently only in combination with a custom flutter embedder engine, but plain dart support should follow soon).
the interop module makes great use of the qml/js interop functions and logic that were written to make `https://github.com/therecipe/entry` possible.
additional languages that are planned to be supported in the near future are: swift, kotlin and haxe (maybe with support for the c#, python and java targets, but if this isn't possible in some clean way then these languages will receive standalone bindings as well).
people using `therecipe/qt` from these new languages should then be able to use flutter (and dart) in combination with qt (and go/js) through this binding and also be able to easily communicate across the language barriers with the help of the interop functions.
the interop engine theoretically also makes a cgo-less `therecipe/qt` usage possible, which could be used to workaround the ever growing annoyances that are experienced when using cgo projects in combination with go modules.
the code for the custom flutter embedder that was created to make the flutter/dart binding work can be found in the `flutter` module. it currently only supports debug builds for the desktop targets, but if there is enough interest, then it shouldn't be too difficult to make release builds there, and on the mobile targets work as well (or even on "embedded" systems such as an raspberry pi for that matter).
an example repo how to use the new flutter/dart binding, will be published in the next few days.

.gitignore

@@ -17,6 +17,8 @@ Mfile*
 */minimal_*
 */*.d.ts
 
+interop/moc*
+
 /internal/binding/dump/*
 /internal/binding/runtime/moc*
 /internal/cmd/moc/test/**/moc*

README.md

@@ -1,26 +1,28 @@
 Introduction
 ------------
 
-[Qt](https://en.wikipedia.org/wiki/Qt_(software)) is a cross-platform application framework that is used for developing application software that can be run on various software and hardware platforms with little or no change in the underlying codebase.
+[Qt](https://en.wikipedia.org/wiki/Qt_(software)) is a free and open-source widget toolkit for creating graphical user interfaces as well as cross-platform applications that run on various software and hardware platforms with little or no change in the underlying codebase.
 
-[Go](https://en.wikipedia.org/wiki/Go_(programming_language)) (often referred to as golang) is a programming language created at Google.
+[Go](https://en.wikipedia.org/wiki/Go_(programming_language)), also known as Golang, is a programming language designed at Google.
 
-This package allows you to write Qt applications entirely in Go and makes deploying them later very easy.
+[therecipe/qt](https://github.com/therecipe/qt) allows you to write Qt applications entirely in Go or JavaScript.
 
-[Gallery](https://github.com/therecipe/qt/wiki/Gallery) of example applications making use of this package.
+Beside the language bindings provided, `therecipe/qt` also greatly simplifies the deployment of Qt applications to various software and hardware platforms.
 
-[WebAssembly Demo (new)](https://therecipe.github.io/entry) | *[repo](https://github.com/therecipe/entry)*
+At the time of writing, almost all Qt functions and classes are accessible from Go and JavaScript, and you should be able to find everything you need to build fully featured Qt applications.
 
-[WebAssembly Demo (old)](https://therecipe.github.io/widgets_playground) | *[repo](https://github.com/therecipe/widgets_playground)*
+Impressions
+-----------
 
-Status
-------
+[Gallery](https://github.com/therecipe/qt/wiki/Gallery) of example applications.
 
-Almost all Qt functions and classes are accessible from Go and you should be able to find everything you need to build fully featured applications.
+[JavaScript Demo](https://therecipe.github.io/entry) | *[source](https://github.com/therecipe/entry)*
 
 Installation
 ------------
 
+The following instructions assume that you already installed [Go](https://golang.org/dl/)
+
 ##### Windows [(more info)](https://github.com/therecipe/qt/wiki/Installation-on-Windows)
 
 ```powershell
@@ -43,7 +45,7 @@ export GO111MODULE=off; go get -v github.com/therecipe/qt/cmd/... && $(go env GO
 Resources
 ---------
 
--	[General Installation](https://github.com/therecipe/qt/wiki/Installation)
+-	[Installation](https://github.com/therecipe/qt/wiki/Installation)
 -	[Getting Started](https://github.com/therecipe/qt/wiki/Getting-Started)
 -	[Wiki](https://github.com/therecipe/qt/wiki)
 -	[Qt Documentation](https://doc.qt.io/qt-5/classes.html)
@@ -76,4 +78,4 @@ License
 
 This package is released under [LGPLv3](https://opensource.org/licenses/LGPL-3.0)
 
-Qt is available under multiple [licenses](https://www.qt.io/licensing)
+Qt itself is licensed and available under multiple [licenses](https://www.qt.io/licensing).

androidextras/androidextras.go

@@ -59,7 +59,8 @@ func NewQAndroidActivityResultReceiverFromPointer(ptr unsafe.Pointer) (n *QAndro
 	return
 }
 
-func (ptr *QAndroidActivityResultReceiver) DestroyQAndroidActivityResultReceiver() {}
+func (ptr *QAndroidActivityResultReceiver) DestroyQAndroidActivityResultReceiver() {
+}
 
 func (ptr *QAndroidActivityResultReceiver) ConnectHandleActivityResult(f func(receiverRequestCode int, resultCode int, data *QAndroidJniObject)) {
 
@@ -111,7 +112,8 @@ func NewQAndroidBinderFromPointer(ptr unsafe.Pointer) (n *QAndroidBinder) {
 	return
 }
 
-func (ptr *QAndroidBinder) DestroyQAndroidBinder() {}
+func (ptr *QAndroidBinder) DestroyQAndroidBinder() {
+}
 
 //go:generate stringer -type=QAndroidBinder__CallType
 //QAndroidBinder::CallType
@@ -180,7 +182,8 @@ func NewQAndroidIntentFromPointer(ptr unsafe.Pointer) (n *QAndroidIntent) {
 	return
 }
 
-func (ptr *QAndroidIntent) DestroyQAndroidIntent() {}
+func (ptr *QAndroidIntent) DestroyQAndroidIntent() {
+}
 
 func NewQAndroidIntent() *QAndroidIntent {
 
@@ -1070,7 +1073,8 @@ func NewQAndroidParcelFromPointer(ptr unsafe.Pointer) (n *QAndroidParcel) {
 	return
 }
 
-func (ptr *QAndroidParcel) DestroyQAndroidParcel() {}
+func (ptr *QAndroidParcel) DestroyQAndroidParcel() {
+}
 
 func NewQAndroidParcel() *QAndroidParcel {
 
@@ -1162,7 +1166,8 @@ func NewQAndroidServiceFromPointer(ptr unsafe.Pointer) (n *QAndroidService) {
 	return
 }
 
-func (ptr *QAndroidService) DestroyQAndroidService() {}
+func (ptr *QAndroidService) DestroyQAndroidService() {
+}
 
 func NewQAndroidService(argc int, argv []string) *QAndroidService {
 
@@ -1324,7 +1329,8 @@ func NewQAndroidServiceConnectionFromPointer(ptr unsafe.Pointer) (n *QAndroidSer
 	return
 }
 
-func (ptr *QAndroidServiceConnection) DestroyQAndroidServiceConnection() {}
+func (ptr *QAndroidServiceConnection) DestroyQAndroidServiceConnection() {
+}
 
 func NewQAndroidServiceConnection() *QAndroidServiceConnection {
 
@@ -1403,7 +1409,8 @@ func NewQtAndroidFromPointer(ptr unsafe.Pointer) (n *QtAndroid) {
 	return
 }
 
-func (ptr *QtAndroid) DestroyQtAndroid() {}
+func (ptr *QtAndroid) DestroyQtAndroid() {
+}
 
 //go:generate stringer -type=QtAndroid__BindFlag
 //QtAndroid::BindFlag

androidextras/androidextras_android.go

@@ -27,7 +27,7 @@ func cGoUnpackBytes(s C.struct_QtAndroidExtras_PackedString) []byte {
 	defer cGoFreePacked(s.ptr)
 	if int(s.len) == -1 {
 		gs := C.GoString(s.data)
-		return *(*[]byte)(unsafe.Pointer(&gs))
+		return []byte(gs)
 	}
 	return C.GoBytes(unsafe.Pointer(s.data), C.int(s.len))
 }

bluetooth/bluetooth.go

@@ -28,7 +28,7 @@ func cGoUnpackBytes(s C.struct_QtBluetooth_PackedString) []byte {
 	defer cGoFreePacked(s.ptr)
 	if int(s.len) == -1 {
 		gs := C.GoString(s.data)
-		return *(*[]byte)(unsafe.Pointer(&gs))
+		return []byte(gs)
 	}
 	return C.GoBytes(unsafe.Pointer(s.data), C.int(s.len))
 }

charts/charts.go

@@ -28,7 +28,7 @@ func cGoUnpackBytes(s C.struct_QtCharts_PackedString) []byte {
 	defer cGoFreePacked(s.ptr)
 	if int(s.len) == -1 {
 		gs := C.GoString(s.data)
-		return *(*[]byte)(unsafe.Pointer(&gs))
+		return []byte(gs)
 	}
 	return C.GoBytes(unsafe.Pointer(s.data), C.int(s.len))
 }

core/core.cpp

@@ -12297,6 +12297,26 @@ long long QLibrary_LoadHints(void* ptr)
 	return static_cast<QLibrary*>(ptr)->loadHints();
 }
 
+void* QLibrary_Resolve(void* ptr, char* symbol)
+{
+	return reinterpret_cast<void*>(static_cast<QLibrary*>(ptr)->resolve(const_cast<const char*>(symbol)));
+}
+
+void* QLibrary_QLibrary_Resolve2(struct QtCore_PackedString fileName, char* symbol)
+{
+	return reinterpret_cast<void*>(QLibrary::resolve(QString::fromUtf8(fileName.data, fileName.len), const_cast<const char*>(symbol)));
+}
+
+void* QLibrary_QLibrary_Resolve3(struct QtCore_PackedString fileName, int verNum, char* symbol)
+{
+	return reinterpret_cast<void*>(QLibrary::resolve(QString::fromUtf8(fileName.data, fileName.len), verNum, const_cast<const char*>(symbol)));
+}
+
+void* QLibrary_QLibrary_Resolve4(struct QtCore_PackedString fileName, struct QtCore_PackedString version, char* symbol)
+{
+	return reinterpret_cast<void*>(QLibrary::resolve(QString::fromUtf8(fileName.data, fileName.len), QString::fromUtf8(version.data, version.len), const_cast<const char*>(symbol)));
+}
+
 void QLibrary_SetFileName(void* ptr, struct QtCore_PackedString fileName)
 {
 	static_cast<QLibrary*>(ptr)->setFileName(QString::fromUtf8(fileName.data, fileName.len));