JavaFX Pitfalls What no documentation tells you Speaker Andy - - PowerPoint PPT Presentation
JavaFX Pitfalls What no documentation tells you Speaker Andy Moncsek Senior Consultant Application Development @andyahcp Trivadis AG Switzerland - Zrich 600 employees in Switzerland, Germany and Austria consulting, development, BI,
Andy Moncsek
Senior Consultant Application Development
Trivadis AG Switzerland - Zürich 600 employees in Switzerland, Germany and Austria consulting, development, BI, infrastructure, operation andy.moncsek@trivadis.com
@andyahcp
Bindings. add(one, two). addListener((x, y, z) -> { if (z != null && z.intValue() == 10) { Alert alert = new Alert(INFORMATION); alert.showAndWait(); } });
Same as:
DoubleBinding b = Bindings.add(one, two); b.addListener((x, y, z) -> { if (z != null && z.intValue() == 10) { Alert alert = new Alert(INFORMATION); alert.showAndWait(); } });
this.b = Bindings.add(one, two); this.b.addListener((x, y, z) -> { if (z != null && z.intValue() == 10) { Alert alert = new Alert(INFORMATION); alert.showAndWait(); } });
@RunWith(JfxRunner.class) public class TestServiceTest {
main thread
@Test public void testLongLastingOperation() { final TestService service = new TestService(); CompletableFuture<String> f = new CompletableFuture<>();
Platform.runLater(() -> {
service.valueProperty().addListener((b, o, n) -> { if (n != null) { f.complete(n); } }); service.restart(); }); assertEquals(„..“, future.get(5, TimeUnit.SECONDS));
} }
@RunWith(JfxRunner.class) public class TestServiceTest {
main thread FX thread
@Test public void testLongLastingOperation() { final TestService service = new TestService(); CompletableFuture<String> f = new CompletableFuture<>();
Platform.runLater(() -> {
service.valueProperty().addListener((b, o, n) -> { if (n != null) { f.complete(n); } }); service.restart(); }); assertEquals(„..“, future.get(5, TimeUnit.SECONDS));
} }
@RunWith(JfxRunner.class) public class TestServiceTest {
@Test public void testLongLastingOperation() { final TestService service = new TestService(); CompletableFuture<String> f = new CompletableFuture<>();
Platform.runLater(() -> {
service.valueProperty().addListener((b, o, n) -> { if (n != null) { f.complete(n); } }); service.restart(); }); assertEquals(„..“, f.get(5, TimeUnit.SECONDS));
} }
main thread FX thread
Don’t create a complex node graph in the UI Thread
(WebSocket, ...)
public class MyApp extends Application { @Override public void init() throws Exception { // Do some heavy lifting } @Override public void start(Stage primaryStage) throws Exception { ... primaryStage.show(); } public static void main(String[] args) { LauncherImpl.launchApplication(MyApp.class,Preloader.class, args); } }
public class MyApp extends Application { @Override public void init() throws Exception { // Do some heavy lifting } @Override public void start(Stage primaryStage) throws Exception { ... primaryStage.show(); } public static void main(String[] args) { LauncherImpl.launchApplication(MyApp.class,Preloader.class, args); } }
FX launcher thread FX thread
public class MyApp extends Application { private InitialUIService service = new InitialUIService(); @Override public void init() throws Exception { // Do some heavy lifting service.start(); } @Override public void start(Stage primaryStage) throws Exception { ... primaryStage.show(); } public static void main(String[] args) { LauncherImpl.launchApplication(MyApp.class,Preloader.class, args); } }
FX launcher thread FX thread Worker thread
SimpleImageInfo info = new SimpleImageInfo(file); double width = info.getWidth(); double height = info.getHeight();
Uses meta-data in header [1] Do not load the whole image !
Image image = new Image("/50mp.jpg", true); double width = image.getWidth(); double height = image.getHeight();
PixelReader PixelWriter getArgb(x,y) setArgb(x,y,value) getColor(x,y) setColor(x,y,value) getPixels(…) setPixels(…)
Example: Crop an image Demo
new WriteableImage() -> QuantumToolkit
public PlatformImage createPlatformImage(int w, int h) { ByteBuffer bytebuf = ...; return com.sun.prism.Image.fromByteBgraPreData(bytebuf, w, h); }
Demo
Canvas: + higher fps
+ lower heap + (~128MB - 250 pic.) + Node count 2
Node: - lower fps
simpleimageinfo/
the-trouble-with-weak-listeners.html
tweaking-the-menu-bar-of-javafx-8-applications-
dependencies
SimpleDoubleProperty prop = new SimpleDoubleProperty(0.0);
for (int i = 0; i < 1000000; ++i) { prop.add(5).multiply(10).dispose(); } prop.unbind(); // will it work?
NO! count WeakListener = 1000000 ! count WeakReference = 1000000 !
SimpleDoubleProperty prop = new SimpleDoubleProperty(0.0);
prop.add(10); // invalidates all ref. !! for (int i = 0; i < 1000000; ++i) { prop.add(5).multiply(10).dispose(); }
new Task<String>() { protected String call() throws Exception { Result r = service.get(); Platform.runLater(()-> .....); Result r2 = service2.get(); Platform.runLater(()-> .....); return "finished - step 2"; } };
FX-Thread Executor-Thread
A.addEventHandler(SUCCEEDED, (s) -> { updateUI(); // start next service B.start(); }); A.addEventHandler(FAILED, (e) -> { doThat(); updateUI(); });
B.setOnSucceeded((state) -> { updateUI(); }); B.setOnFailed((event) -> { doThat(); updateUI(); });
FX-Thread Executor-Thread
handler .supplyAsync(()->longRunningTask1()) .onError(this::updateErrorMessage) .consumeOnFXThread(stringVal -> vbox.getChildren(). add(new Button(stringVal)) ) .supplyAsync(()->longRunningTask2()) .onError(this::updateErrorMessage)
.execute(this::updateUI); //non-blocking!
FX-Thread Executor-Thread
final TestService service = new TestService();
IntStream.range(0, 5).forEach(v -> { handler.supplyOnFXThread(() -> { registerListenerAndStart(service, waitLatch); return service; }).functionOnExecutorThread((service) -> { // wait outside FX application thread !!! waitForService(waitLatch); return service; }).execute(serv -> { assertEquals("I'm an expensive result.", serv.getValue()); stop.countDown(); }); awaitServiceDone(stop); });
main thread FX thread
final TestService service = new TestService();
IntStream.range(0, 5).forEach(v -> { handler.supplyOnFXThread(() -> { registerListenerAndStart(service, waitLatch); return service; }).functionOnExecutorThread((service) -> { // wait outside FX application thread !!! awaitService(waitLatch); return service; }).execute(serv -> { assertEquals("I'm an expensive result.", serv.getValue()); stop.countDown(); }); // Non-blocking !!! awaitServiceResult(stop); });
main thread FX thread worker thread
Eclipse SWT -> Cocoa native binding JavaFX wrapper: NSMenuFX [3] better