android_sample/SampleApp/jni/sample-jni.cpp

/*
 * Copyright (C) 2011 Skia
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

#include <jni.h>

#include "SkCanvas.h"
#include "GraphicsJNI.h"
#include "SkEvent.h"
#include "SkWindow.h"
#include "SkApplication.h"
#include "utils/android/AndroidKeyToSkKey.h"

///////////////////////////////////////////
///////////////// Globals /////////////////
///////////////////////////////////////////

struct ActivityGlue {
    JNIEnv* m_env;
    jweak m_obj;
    jmethodID m_setTitle;
    ActivityGlue() {
        m_env = NULL;
        m_obj = NULL;
        m_setTitle = NULL;
    }
} gActivityGlue;

struct WindowGlue {
    jweak m_obj;
    jmethodID m_inval;
    WindowGlue() {
        m_obj = NULL;
        m_inval = NULL;
    }
} gWindowGlue;

SkOSWindow* gWindow;

///////////////////////////////////////////
///////////// SkOSWindow impl /////////////
///////////////////////////////////////////

void SkOSWindow::onSetTitle(const char title[])
{
    if (gActivityGlue.m_env) {
        JNIEnv* env = gActivityGlue.m_env;
        jstring string = env->NewStringUTF(title);
        env->CallVoidMethod(gActivityGlue.m_obj, gActivityGlue.m_setTitle,
                string);
        env->DeleteLocalRef(string);
    }
}

void SkOSWindow::onHandleInval(const SkIRect& rect)
{
    if (!gActivityGlue.m_env || !gWindowGlue.m_inval || !gWindowGlue.m_obj) {
        return;
    }
    gActivityGlue.m_env->CallVoidMethod(gWindowGlue.m_obj, gWindowGlue.m_inval,
            rect.fLeft, rect.fTop, rect.fRight, rect.fBottom);
}

///////////////////////////////////////////
/////////////// SkEvent impl //////////////
///////////////////////////////////////////

void SkEvent::SignalQueueTimer(SkMSec) {}

void SkEvent::SignalNonEmptyQueue() {}

///////////////////////////////////////////
////////////////// JNI ////////////////////
///////////////////////////////////////////

static jmethodID GetJMethod(JNIEnv* env, jclass clazz, const char name[],
        const char signature[])
{
    jmethodID m = env->GetMethodID(clazz, name, signature);
    if (!m) SkDebugf("Could not find Java method %s\n", name);
    return m;
}

extern "C" {
JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_drawToCanvas(
        JNIEnv* env, jobject thiz, jobject jcanvas);
JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_init(
        JNIEnv* env, jobject thiz);
JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_term(
        JNIEnv* env, jobject thiz);
JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_updateSize(
        JNIEnv* env, jobject thiz, jint w, jint h);
JNIEXPORT bool JNICALL Java_com_skia_sampleapp_SampleApp_handleKeyDown(
        JNIEnv* env, jobject thiz, jint keyCode, jint uni);
JNIEXPORT bool JNICALL Java_com_skia_sampleapp_SampleApp_handleKeyUp(
        JNIEnv* env, jobject thiz, jint keyCode);
JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_handleClick(
        JNIEnv* env, jobject thiz, jint x, jint y, jint state);
JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_createOSWindow(
        JNIEnv* env, jobject thiz, jobject jsampleView);
};

JNIEXPORT bool JNICALL Java_com_skia_sampleapp_SampleApp_handleKeyDown(
        JNIEnv* env, jobject thiz, jint keyCode, jint uni)
{
    bool handled = gWindow->handleKey(AndroidKeycodeToSkKey(keyCode));
    handled |= gWindow->handleChar((SkUnichar) uni);
    return handled;
}

JNIEXPORT bool JNICALL Java_com_skia_sampleapp_SampleApp_handleKeyUp(JNIEnv* env,
        jobject thiz, jint keyCode)
{
    return gWindow->handleKeyUp(AndroidKeycodeToSkKey(keyCode));
}

JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_handleClick(JNIEnv* env,
        jobject thiz, jint x, jint y, jint jstate)
{
    SkView::Click::State state;
    switch(jstate) {
        case 0:     // MotionEvent.ACTION_DOWN
            state = SkView::Click::kDown_State;
            break;
        case 1:     // MotionEvent.ACTION_UP
        case 3:     // MotionEvent.ACTION_CANCEL
            state = SkView::Click::kUp_State;
            break;
        case 2:     // MotionEvent.ACTION_MOVE
            state = SkView::Click::kMoved_State;
            break;
        default:
            SkDebugf("motion event ignored\n");
            return;
    }
    gWindow->handleClick(x, y, state);
}

JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_updateSize(JNIEnv* env,
        jobject thiz, jint w, jint h)
{
    gWindow->resize(w, h);
}

JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_createOSWindow(
        JNIEnv* env, jobject thiz, jobject jsampleView)
{
    gWindow = create_sk_window(NULL);
    // Only using a method on View.
    jclass clazz = gActivityGlue.m_env->FindClass("android/view/View");
    gWindowGlue.m_obj = gActivityGlue.m_env->NewWeakGlobalRef(jsampleView);
    gWindowGlue.m_inval = GetJMethod(gActivityGlue.m_env, clazz, "invalidate",
            "(IIII)V");
    gActivityGlue.m_env->DeleteLocalRef(clazz);
}

JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_init(JNIEnv* env,
        jobject thiz)
{
    gActivityGlue.m_env = env;
    // Only using a method on Activity.
    jclass clazz = env->FindClass("android/app/Activity");
    gActivityGlue.m_obj = env->NewWeakGlobalRef(thiz);
    gActivityGlue.m_setTitle = GetJMethod(env, clazz, "setTitle",
            "(Ljava/lang/CharSequence;)V");
    env->DeleteLocalRef(clazz);

    application_init();
}

JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_term(JNIEnv* env,
        jobject thiz)
{
    application_term();
    if (gWindowGlue.m_obj) {
        env->DeleteWeakGlobalRef(gWindowGlue.m_obj);
        gWindowGlue.m_obj = NULL;
    }
    if (gActivityGlue.m_obj) {
        env->DeleteWeakGlobalRef(gActivityGlue.m_obj);
        gActivityGlue.m_obj = NULL;
    }
    delete gWindow;
    gWindow = NULL;
}


JNIEXPORT void JNICALL Java_com_skia_sampleapp_SampleApp_drawToCanvas(
        JNIEnv* env, jobject thiz, jobject jcanvas)
{
    if (!gWindow) return;
    gWindow->update(NULL);
    SkCanvas* canvas = GraphicsJNI::getNativeCanvas(env, jcanvas);
    canvas->drawBitmap(gWindow->getBitmap(), 0, 0);
}