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-rw-r--r--Examples/go/callback/Makefile12
-rw-r--r--Examples/go/callback/example.h1
-rw-r--r--Examples/go/callback/gocallback.go41
-rw-r--r--Examples/go/callback/index.html64
-rw-r--r--Examples/go/callback/runme.go16
5 files changed, 62 insertions, 72 deletions
diff --git a/Examples/go/callback/Makefile b/Examples/go/callback/Makefile
index bf5275f14..7441e09bd 100644
--- a/Examples/go/callback/Makefile
+++ b/Examples/go/callback/Makefile
@@ -1,6 +1,7 @@
TOP = ../..
SWIG = $(TOP)/../preinst-swig
CXXSRCS = callback.cxx
+GOSRCS = gocallback.go
TARGET = example
INTERFACE = example.i
SWIGOPT =
@@ -9,8 +10,15 @@ check: build
$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' CXXSRCS='$(CXXSRCS)' TARGET='$(TARGET)' INTERFACE='$(INTERFACE)' go_run
build:
- $(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' CXXSRCS='$(CXXSRCS)' SWIG='$(SWIG)' \
- SWIGOPT='$(SWIGOPT)' TARGET='$(TARGET)' INTERFACE='$(INTERFACE)' go_cpp
+ if [ -n '$(SRCDIR)' ]; then \
+ cp $(GOSRCS:%=$(SRCDIR)/%) .; \
+ fi
+ @# Note: example.go gets generated by SWIG
+ $(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' CXXSRCS='$(CXXSRCS)' GOSRCS='example.go $(GOSRCS)' \
+ SWIG='$(SWIG)' SWIGOPT='$(SWIGOPT)' TARGET='$(TARGET)' INTERFACE='$(INTERFACE)' go_cpp
clean:
+ if [ -n '$(SRCDIR)' ]; then \
+ rm $(GOSRCS) || true; \
+ fi
$(MAKE) -f $(TOP)/Makefile SRCDIR='$(SRCDIR)' INTERFACE='$(INTERFACE)' go_clean
diff --git a/Examples/go/callback/example.h b/Examples/go/callback/example.h
index 1a0e8c432..74ddad954 100644
--- a/Examples/go/callback/example.h
+++ b/Examples/go/callback/example.h
@@ -20,4 +20,3 @@ public:
void setCallback(Callback *cb) { delCallback(); _callback = cb; }
void call() { if (_callback) _callback->run(); }
};
-
diff --git a/Examples/go/callback/gocallback.go b/Examples/go/callback/gocallback.go
new file mode 100644
index 000000000..20fd0627a
--- /dev/null
+++ b/Examples/go/callback/gocallback.go
@@ -0,0 +1,41 @@
+package example
+
+import (
+ "fmt"
+)
+
+type GoCallback interface {
+ Callback
+ deleteCallback()
+ IsGoCallback()
+}
+
+type goCallback struct {
+ Callback
+}
+
+func (p *goCallback) deleteCallback() {
+ DeleteDirectorCallback(p.Callback)
+}
+
+func (p *goCallback) IsGoCallback() {}
+
+type overwrittenMethodsOnCallback struct {
+ p Callback
+}
+
+func NewGoCallback() GoCallback {
+ om := &overwrittenMethodsOnCallback{}
+ p := NewDirectorCallback(om)
+ om.p = p
+
+ return &goCallback{Callback: p}
+}
+
+func DeleteGoCallback(p GoCallback) {
+ p.deleteCallback()
+}
+
+func (p *goCallback) Run() {
+ fmt.Println("GoCallback.Run")
+}
diff --git a/Examples/go/callback/index.html b/Examples/go/callback/index.html
index b053cf547..9a53065b0 100644
--- a/Examples/go/callback/index.html
+++ b/Examples/go/callback/index.html
@@ -12,67 +12,17 @@
<H2>Implementing C++ callbacks in Go</H2>
<p>
-This example illustrates how to use directors to implement C++
-callbacks in Go.
-</p>
-
-<p>
-Because Go and C++ use inheritance differently, you must call a
-different function to create a class which uses callbacks. Instead of
-calling the usual constructor function whose name is <tt>New</tt>
-followed by the capitalized name of the class, you call a function
-named <tt>NewDirector</tt> followed by the capitalized name of the
-class.
-</p>
-
-<p>
-The first argument to the <tt>NewDirector</tt> function is an instance
-of a type. The <tt>NewDirector</tt> function will return an interface
-value as usual. However, when calling any method on the returned
-value, the program will first check whether the value passed
-to <tt>NewDirector</tt> implements that method. If it does, the
-method will be called in Go. This is true whether the method is
-called from Go code or C++ code.
-</p>
-
-<p>
-Note that the Go code will be called with just the Go value, not the
-C++ value. If the Go code needs to call a C++ method on itself, you
-need to get a copy of the C++ object. This is typically done as
-follows:
-
-<blockquote>
-<pre>
-type Child struct { abi Parent }
-func (p *Child) ChildMethod() {
- p.abi.ParentMethod()
-}
-func f() {
- p := &Child{nil}
- d := NewDirectorParent(p)
- p.abi = d
- ...
-}
-</pre>
-</blockquote>
-
-In other words, we first create the Go value. We pass that to
-the <tt>NewDirector</tt> function to create the C++ value; this C++
-value will be created with an association to the Go value. We then
-store the C++ value in the Go value, giving us the reverse
-association. That permits us to call parent methods from the child.
-
-</p>
-
-<p>
-To delete a director object, use the function <tt>DeleteDirector</tt>
-followed by the capitalized name of the class.
+This example illustrates how to use directors to implement C++ callbacks in Go.
+See the <a href="../../../Doc/Manual/Go.html#Go_director_classes">Go Director
+Classes</a> documentation subsection for an in-depth explanation how to use the
+director feature.
</p>
<p>
<ul>
-<li><a href="example.h">example.h</a>. Header file containing some enums.
-<li><a href="example.i">example.i</a>. Interface file.
+<li><a href="example.h">example.h</a>. Header with the definition of the Caller and Callback classes.
+<li><a href="example.i">example.i</a>. SWIG interface file.
+<li><a href="gocallback.go">gocallback.go</a>. Go source with the definition of the GoCallback class.
<li><a href="runme.go">runme.go</a>. Sample Go program.
</ul>
diff --git a/Examples/go/callback/runme.go b/Examples/go/callback/runme.go
index 2eef77fdb..03ab0c5e2 100644
--- a/Examples/go/callback/runme.go
+++ b/Examples/go/callback/runme.go
@@ -16,26 +16,18 @@ func main() {
caller.Call()
caller.DelCallback()
- callback = NewDirectorCallback(new(GoCallback))
+ go_callback := NewGoCallback()
fmt.Println()
fmt.Println("Adding and calling a Go callback")
- fmt.Println("------------------------------------")
+ fmt.Println("--------------------------------")
- caller.SetCallback(callback)
+ caller.SetCallback(go_callback)
caller.Call()
caller.DelCallback()
- // Test that a double delete does not occur as the object has
- // already been deleted from the C++ layer.
- DeleteDirectorCallback(callback)
+ DeleteGoCallback(go_callback)
fmt.Println()
fmt.Println("Go exit")
}
-
-type GoCallback struct{}
-
-func (p *GoCallback) Run() {
- fmt.Println("GoCallback.Run")
-}