fix blocking sync callbacks for qtbox + new 3rdparty/mpv example

internal/binding/files/utils-qml.go

@@ -22,7 +22,7 @@ var (
 
 	//needed only for interop  --->
 	ReturnPointersAsStrings     bool
-	SupportsSyncCallsIntoRemote bool
+	SupportsSyncCallsIntoRemote = true
 
 	syncCallIntoRemoteChan       = make(chan string, 0)
 	syncCallIntoRemoteReturnChan = make(chan string, 0)

internal/examples/3rdparty/mpv/demo/main.go

@@ -0,0 +1,26 @@
+//source: https://github.com/mpv-player/mpv-examples/tree/master/libmpv/qml
+
+package main
+
+import (
+	"os"
+
+	"github.com/therecipe/qt/core"
+	"github.com/therecipe/qt/gui"
+	"github.com/therecipe/qt/quick"
+
+	"github.com/therecipe/qt/internal/examples/3rdparty/mpv"
+)
+
+func main() {
+	gui.NewQGuiApplication(len(os.Args), os.Args)
+
+	mpv.InitMpv()
+
+	view := quick.NewQQuickView(nil)
+	view.SetResizeMode(quick.QQuickView__SizeRootObjectToView)
+	view.SetSource(core.NewQUrl3("qrc:/qml/main.qml", 0)) //qrc:/mpvtest/main.qml should work as well, since init.go is not patching out the embedding
+	view.Show()
+
+	gui.QGuiApplication_Exec()
+}

internal/examples/3rdparty/mpv/demo/qml/main.qml

@@ -0,0 +1,71 @@
+import QtQuick 2.0
+import QtQuick.Controls 1.0
+
+import mpvtest 1.0
+
+Item {
+    width: 1280
+    height: 720
+
+    MpvObject {
+        id: renderer
+        anchors.fill: parent
+
+        MouseArea {
+            anchors.fill: parent
+            onClicked: renderer.command(["loadfile", "test.mkv"])
+        }
+    }
+
+    Rectangle {
+        id: labelFrame
+        anchors.margins: -50
+        radius: 5
+        color: "white"
+        border.color: "black"
+        opacity: 0.8
+        anchors.fill: box
+    }
+
+    Row {
+        id: box
+        anchors.bottom: renderer.bottom
+        anchors.left: renderer.left
+        anchors.right: renderer.right
+        anchors.margins: 100
+
+        Text {
+            anchors.margins: 10
+            wrapMode: Text.WordWrap
+            text: "QtQuick and mpv are both rendering stuff.\n
+                   Click to load test.mkv"
+        }
+
+        // Don't take these controls too seriously. They're for testing.
+        Column {
+            CheckBox {
+                id: checkbox
+                anchors.margins: 10
+                // Heavily filtered means good, right?
+                text: "Make video look like on a Smart TV"
+                onClicked: {
+                    if (checkbox.checked) {
+                        renderer.setProperty("sharpen", 5.0)
+                    } else {
+                        renderer.setProperty("sharpen", 0)
+                    }
+                }
+            }
+            Slider {
+                id: slider
+                anchors.margins: 10
+                anchors.left: checkbox.left
+                anchors.right: checkbox.right
+                minimumValue: -100
+                maximumValue:  100
+                value: 0
+                onValueChanged: renderer.setProperty("gamma", slider.value | 0)
+            }
+        }
+    }
+}

internal/examples/3rdparty/mpv/init.go

@@ -0,0 +1,66 @@
+// +build ignore
+
+package main
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strconv"
+)
+
+func main() {
+	if _, ok := os.LookupEnv("QT_PKG_CONFIG"); !ok {
+		println("please export QT_PKG_CONFIG")
+		os.Exit(1)
+	}
+
+	pwd, pwdErr := os.Getwd()
+	if pwdErr != nil {
+		println("failed to get PWD", pwdErr.Error())
+		os.Exit(1)
+	}
+
+	if _, err := os.Stat("mpv-examples"); err == nil {
+		println("mpv-examples already cloned")
+	} else {
+		if out, err := exec.Command("git", "clone", "--depth=1", "https://github.com/mpv-player/mpv-examples.git").CombinedOutput(); err != nil {
+			println("failed to clone mpv-examples", err.Error())
+			println(string(out))
+			os.Exit(1)
+		}
+		println("cloned mpv-examples")
+	}
+
+	//patch *.pro to build a static lib
+	exec.Command("bash", "-c", fmt.Sprintf("echo \"TEMPLATE = lib\" >> %v", filepath.Join(pwd, "mpv-examples", "libmpv", "qml", "mpvtest.pro"))).CombinedOutput()
+	exec.Command("bash", "-c", fmt.Sprintf("echo \"CONFIG += staticlib\" >> %v", filepath.Join(pwd, "mpv-examples", "libmpv", "qml", "mpvtest.pro"))).CombinedOutput()
+
+	//patch main.cpp
+	exec.Command("bash", "-c", fmt.Sprintf("head -n -17 %[1]v > %[2]v && mv %[2]v %[1]v", filepath.Join(pwd, "mpv-examples", "libmpv", "qml", "main.cpp"), filepath.Join(pwd, "mpv-examples", "libmpv", "qml", "copy_main.cpp"))).CombinedOutput()
+	exec.Command("bash", "-c", fmt.Sprintf("echo 'extern \"C\" void initMpv() { std::setlocale(LC_NUMERIC, \"C\"); qmlRegisterType<MpvObject>(\"mpvtest\", 1, 0, \"MpvObject\");	}' >> %[1]v", filepath.Join(pwd, "mpv-examples", "libmpv", "qml", "main.cpp"))).CombinedOutput()
+
+	//only tested on arch, since the libmpv version is quite old on ubuntu 16.04 and 18.04
+	for _, target := range []string{runtime.GOOS} {
+
+		qCmd := exec.Command("qmake", "mpvtest.pro")
+		qCmd.Dir = filepath.Join(pwd, "mpv-examples", "libmpv", "qml")
+		if out, err := qCmd.CombinedOutput(); err != nil {
+			println("failed to generate makefile for", target, err.Error())
+			println(string(out))
+			os.Exit(1)
+		}
+		println("generated makefile for", target)
+
+		iCmd := exec.Command("make", "-j", strconv.Itoa(runtime.NumCPU()))
+		iCmd.Dir = filepath.Join(pwd, "mpv-examples", "libmpv", "qml")
+		if out, err := iCmd.CombinedOutput(); err != nil {
+			println("failed to make mpv-examples for", target)
+			println(string(out))
+			os.Exit(1)
+		}
+		println("built mpv-examples for", target)
+	}
+}

internal/examples/3rdparty/mpv/mpv.go

@@ -0,0 +1,19 @@
+package mpv
+
+/*
+#cgo pkg-config: mpv
+#cgo linux,amd64 LDFLAGS: -L ${SRCDIR}/mpv-examples/libmpv/qml -lmpvtest
+
+void initMpv();
+*/
+import "C"
+import (
+	"github.com/therecipe/qt/core"
+	_ "github.com/therecipe/qt/quick"
+)
+
+type stub struct{ core.QObject } //TODO: needed for linking at the moment
+
+func InitMpv() {
+	C.initMpv()
+}

interop/interop.go

@@ -22,7 +22,7 @@ var (
 
 	//needed only for interop  --->
 	ReturnPointersAsStrings     bool
-	SupportsSyncCallsIntoRemote bool
+	SupportsSyncCallsIntoRemote = true
 
 	syncCallIntoRemoteChan       = make(chan string, 0)
 	syncCallIntoRemoteReturnChan = make(chan string, 0)

qml/utils-qml.go

@@ -22,7 +22,7 @@ var (
 
 	//needed only for interop  --->
 	ReturnPointersAsStrings     bool
-	SupportsSyncCallsIntoRemote bool
+	SupportsSyncCallsIntoRemote = true
 
 	syncCallIntoRemoteChan       = make(chan string, 0)
 	syncCallIntoRemoteReturnChan = make(chan string, 0)