SkiaExamples improvements.

experimental/SkiaExamples/SkExample.h

 /*
  * Copyright 2013 Google Inc.
  *
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  */
 
-#ifndef BaseExample_DEFINED
-#define BaseExample_DEFINED
+#ifndef SkExample_DEFINED
+#define SkExample_DEFINED
 
 #include "SkWindow.h"
 
 class GrContext;
 struct GrGLInterface;
 class GrRenderTarget;
 class SkCanvas;
 
-class BaseExample : public SkOSWindow {
+class HelloSkia;

[caryclark, 2013/07/08 12:42:35]

remove this if it isn't required for this header

+
+class SkExample : public SkOSWindow {
 public:
+    /**
+     * Member function that creates the SkExample. By default it will create a sample
+     * defined in SkExample.cpp
+     * The user of this framework can register a new (and only one) example by running:
+     *
+     * SkExample::SetExample<DerivedClass> reg("My derived class");
+     *
+     * ... where DerivedClass is a child of SkExample and 'reg' can be any name.
+     *
+     */
+    static SkOSWindow* (*create_user_example) (void* hwnd, int argc, char** argv);

[caryclark, 2013/07/08 12:42:35]

use gCreateUserExample to hint to reader that this is a global variable
(gUserExampleFuncPtr might be better)
create_user_example looks like its a local (non-exported) function

also, public variables are usually at the bottom of the class, just above the
private: section

+
+    template<typename T>
+    class SetExample {
+        public:

[caryclark, 2013/07/08 12:42:35]

unindent

+            static SkOSWindow* create(void* hwnd, int argc, char** argv) {
+                return new T(hwnd, argc, argv);
+            }

[caryclark, 2013/07/08 12:42:35]

add a blank line here

+            SetExample(const char* name) {
+                if (SkExample::userExampleExists) {
+                    SkDebugf("Rejecting the following Skia Example: %s\n", name);
+                    return;
+                }
+                SkDebugf("Using skia example: %s\n", name);
+                SkExample::create_user_example = &create;
+                SkExample::userExampleExists = true;
+            }
+    };
+
     enum DeviceType {
         kRaster_DeviceType,
         kGPU_DeviceType,
     };
-    BaseExample(void* hWnd, int argc, char** argv);
+    SkExample(void* hWnd, int argc, char** argv);
 
     // Changes the device type of the object.
     bool setupBackend(DeviceType type);
     void tearDownBackend();
 
     DeviceType getDeviceType() const { return fType; }
 
 protected:
     // Your class should override this method to do its thing.
     virtual void draw(SkCanvas* canvas) SK_OVERRIDE;
 
     virtual void onSizeChange() SK_OVERRIDE;
 
 #ifdef SK_BUILD_FOR_WIN
     virtual void onHandleInval(const SkIRect&) SK_OVERRIDE;
 #endif
 
     SkCanvas* createCanvas() SK_OVERRIDE;
 
 private:
+    static bool userExampleExists;

[caryclark, 2013/07/08 12:42:35]

use 'gUserExampleExists' to hint to reader that this is a global

+
     void setupRenderTarget();
 
     DeviceType fType;
 
     GrContext* fContext;
     GrRenderTarget* fRenderTarget;
     AttachmentInfo fAttachmentInfo;
     const GrGLInterface* fInterface;
+
     typedef SkOSWindow INHERITED;
 };
+
 #endif
+