如何以Java实现网页截图技术
使用JavaFX8（JDK8打包在一起）
public void start(Stage primaryStage) throws Exception {
final WebView view = new WebView();
Scene scene = new Scene(view, 310, 310);
primaryStage.setScene(scene);
final WebEngine webEngine = view.getEngine();
webEngine.load(this.getClass().getResource("web/index.html")
.toExternalForm());
primaryStage.show();
// 方式1. 监听webEngine加载进度，可能页面加载不完整
webEngine.getLoadWorker().stateProperty()
.addListener(new ChangeListener<State>() {
@Override
public void changed(ObservableValue<? extends State> ov,
State oldState, State newState) {
if (newState == State.SUCCEEDED) {
snapshot(view);
}
}
});
// 方式2. 使用Transition设定延时
PauseTransition ptr = new PauseTransition(Duration.seconds(3));
ptr.setOnFinished(new EventHandler<ActionEvent>() {
@Override
public void handle(ActionEvent event) {
snapshot(view);
}
});
ptr.play();
//方式3. 使用Task设定延时
Task<String> task = new Task<String>() {
@Override
protected String call() throws Exception {
Thread.sleep(5000);
return null;
}
};
task.setOnSucceeded(new EventHandler<WorkerStateEvent>() {
@Override
public void handle(WorkerStateEvent event) {
snapshot(view);
}
});
new Thread(task).start();
// 方式4. 自己实现多线程调用，较麻烦
new Thread(){
public void run() {
try {
Thread.sleep(7000);//该命令不可直接在Fx用户线程执行，否则会导致前台的渲染线程暂停，页面不会被加载
Platform.runLater(new Runnable() {
@Override
public void run() {
snapshot(view);//在后台线程中不可以直接操作UI，需要借助runLater
}
});
} catch (InterruptedException e) {
e.printStackTrace();
}
};
}.start();
}
public void snapshot(Node view) {
Image image = view.snapshot(null, null);
try {
ImageIO.write(SwingFXUtils.fromFXImage(image, null), "png",
new File("f:\\" + System.currentTimeMillis() + ".png"));
} catch (IOException e) {
e.printStackTrace();
}
}
