Initial commit of our new Android app to demo Skia.

tools/viewer/sk_app/android/surface_glue_android.cpp

Index: tools/viewer/sk_app/android/surface_glue_android.cpp
diff --git a/tools/viewer/sk_app/android/surface_glue_android.cpp b/tools/viewer/sk_app/android/surface_glue_android.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..e287afa43b43ea385985ca2c65e70450d01d7464
--- /dev/null
+++ b/tools/viewer/sk_app/android/surface_glue_android.cpp
@@ -0,0 +1,169 @@
+/*
+* Copyright 2016 Google Inc.
+*
+* Use of this source code is governed by a BSD-style license that can be
+* found in the LICENSE file.
+*/
+
+#include "surface_glue_android.h"
+
+#include <jni.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include <android/native_window_jni.h>
+#include <android_native_app_glue.h>

[djsollen, 2016/05/06 18:45:26]

we should not need this include.

[liyuqian, 2016/05/06 20:42:30]

This is needed for LOOPER_ID_USER

[djsollen, 2016/05/09 13:29:44]

you don't need LOOPER_ID_USER as that was something specific to
android_native_app_glue.  You only have one looper so you can replace the line
below with 

static const int LOOPER_ID_USER = 1;

[liyuqian, 2016/05/09 14:27:27]

Done.

+
+#include "../Application.h"
+#include "SkTypes.h"
+#include "SkUtils.h"
+#include "Window_android.h"
+
+namespace sk_app {
+
+static const int LOOPER_ID_MESSAGEPIPE = LOOPER_ID_USER;
+
+void* pthread_main(void* arg);
+
+AppThread::AppThread() {
+    nativeWindow = nullptr;
+    pthread_create(&thread, nullptr, pthread_main, this);
+}
+
+AppThread::~AppThread() {
+    if (window) {
+        window->detach();
+    }
+    if (nativeWindow) {
+        ANativeWindow_release(this->nativeWindow);
+        this->nativeWindow = nullptr;
+    }
+    if (app) {
+        delete app;
+    }
+}
+
+void AppThread::postMessage(const Message& message) {
+    auto writeSize = write(pipes[1], &message, sizeof(message));
+    SkASSERT(writeSize == sizeof(message));
+}
+
+void AppThread::readMessage(Message* message) {
+    auto readSize = read(pipes[0], message, sizeof(Message));
+    SkASSERT(readSize == sizeof(Message));
+}
+
+static int message_callback(int fd, int events, void* data) {
+    auto appThread = (AppThread*)data;
+    Message message;
+    appThread->readMessage(&message);
+    SkDebugf("message_callback %d", message.type);
+
+    switch (message.type) {
+        case kDestroyApp: {
+            delete appThread;
+            pthread_exit(nullptr);
+            return 0;
+        }
+        case kSurfaceCreated: {
+            auto window_android = (Window_android*)appThread->window;
+            window_android->initDisplay(appThread->nativeWindow);
+            window_android->paintIfNeeded();
+            break;
+        }
+        case kSurfaceChanged: {
+            int width = ANativeWindow_getWidth(appThread->nativeWindow);
+            int height = ANativeWindow_getHeight(appThread->nativeWindow);
+            appThread->window->onResize(width, height);
+            auto window_android = (Window_android*)appThread->window;
+            window_android->setContentRect(0, 0, width, height);
+            window_android->paintIfNeeded();
+            break;
+        }
+        default: {
+            // do nothing
+        }
+    }
+
+    return 1;  // continue receiving callbacks
+}
+
+void* pthread_main(void* arg) {
+    SkDebugf("pthread_main begins");
+
+    auto appThread = (AppThread*)arg;
+
+    ALooper* looper = ALooper_prepare(ALOOPER_PREPARE_ALLOW_NON_CALLBACKS);
+    pipe(appThread->pipes);
+    ALooper_addFd(looper, appThread->pipes[0], LOOPER_ID_MESSAGEPIPE, ALOOPER_EVENT_INPUT,
+                  message_callback, appThread);
+
+    int ident;
+    int events;
+    struct android_poll_source* source;
+
+    appThread->app = Application::Create(0, nullptr, appThread);
+
+    while ((ident = ALooper_pollAll(-1, nullptr, &events, (void**)&source)) >= 0) {
+        SkDebugf("ALooper_pollAll ident=%d", ident);
+    }
+
+    return nullptr;
+}
+
+extern "C"  // extern "C" is needed for JNI (although the method itself is in C++)
+    JNIEXPORT jlong JNICALL
+    Java_org_skia_viewer_ViewerApplication_createNativeApp(JNIEnv* env, jobject activity) {
+    AppThread* appThread = new AppThread;
+    return (jlong)((size_t)appThread);
+}
+
+extern "C" JNIEXPORT void JNICALL Java_org_skia_viewer_ViewerApplication_destroyNativeApp(
+    JNIEnv* env, jobject activity, jlong handle) {
+    auto appThread = (AppThread*)handle;
+    Message message(kDestroyApp);
+    appThread->postMessage(message);
+    pthread_join(appThread->thread, nullptr);
+}
+
+extern "C" JNIEXPORT void JNICALL Java_org_skia_viewer_MainActivity_onSurfaceCreated(
+    JNIEnv* env, jobject activity, jlong handle, jobject surface) {
+    auto appThread = (AppThread*)handle;
+
+    SkASSERT(!appThread->nativeWindow);
+    ANativeWindow* nativeWindow = ANativeWindow_fromSurface(env, surface);
+    appThread->nativeWindow = nativeWindow;
+
+    Message message(kSurfaceCreated);
+    appThread->postMessage(message);
+}
+
+extern "C" JNIEXPORT void JNICALL Java_org_skia_viewer_MainActivity_onSurfaceChanged(
+    JNIEnv* env, jobject activity, jlong handle, jobject surface) {
+    auto appThread = (AppThread*)handle;
+
+    ANativeWindow* nativeWindow = ANativeWindow_fromSurface(env, surface);
+    if (nativeWindow != appThread->nativeWindow) {
+        ANativeWindow_release(appThread->nativeWindow);
+        appThread->nativeWindow = nativeWindow;
+    }
+
+    Message message(kSurfaceChanged);
+    appThread->postMessage(message);
+}
+
+extern "C" JNIEXPORT void JNICALL
+Java_org_skia_viewer_MainActivity_onSurfaceDestroyed(JNIEnv* env, jobject activity, jlong handle) {
+    auto appThread = (AppThread*)handle;
+
+    if (appThread->nativeWindow) {
+        ANativeWindow_release(appThread->nativeWindow);
+        appThread->nativeWindow = nullptr;
+    }
+
+    Message message(kSurfaceDestroyed);
+    appThread->postMessage(message);
+}
+
+}  // namespace sk_app