JavaFX 新手
此示例适用于小图像。
但是大图像会使 ImageView 崩溃。
我的示例代码有缺陷吗？
JavaFX 中的大图像有问题吗？
还有别的事吗？
我从网上抓了一个例子：
http://www.java2s.com/Code/Java/JavaFX/JavaFXImageZoomExample.htm http://www.java2s.com/Code/Java/JavaFX/JavaFXImageZoomExample.htm
我下载并处理 PDF 文件：
http://optics.byu.edu/BYUOpticsBook_2013.pdf http://optics.byu.edu/BYUOpticsBook_2013.pdf
gs -sDEVICE=png16m -dNOPAUSE -dBATCH -dSAFER \
-r600 -dFirstPage=1 -dLastPage=1 \
-sOutputFile=001.png BYUOpticsBook_2013.pdf
这给了我一个 5100 × 6600 像素的图像。
我尝试查看图像：
几秒钟后出现一个窗口，其中有一个空的
滚动窗格和发送到控制台的堆栈跟踪。
import javafx.application.Application;
import javafx.beans.InvalidationListener;
import javafx.beans.Observable;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.SimpleDoubleProperty;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.ScrollPane;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.input.ScrollEvent;
import javafx.stage.Stage;
/**
*
* @author O.J. Sousa Rodrigues (office at halbgasse.at)
*/
public class ZoomExample extends Application {
private ImageView imageView = new ImageView();
private ScrollPane scrollPane = new ScrollPane();
final DoubleProperty zoomProperty = new SimpleDoubleProperty(200);
@Override
public void start(Stage stage) throws Exception {
zoomProperty.addListener(new InvalidationListener() {
@Override
public void invalidated(Observable arg0) {
imageView.setFitWidth(zoomProperty.get() * 4);
imageView.setFitHeight(zoomProperty.get() * 3);
}
});
scrollPane.addEventFilter(ScrollEvent.ANY,
new EventHandler<ScrollEvent>() {
@Override
public void handle(ScrollEvent event) {
if (event.getDeltaY() > 0) {
zoomProperty.set(zoomProperty.get() * 1.1);
} else if (event.getDeltaY() < 0) {
zoomProperty.set(zoomProperty.get() / 1.1);
}
}
});
imageView.setImage(new Image("file:///home/jeff/001.png"));
imageView.preserveRatioProperty().set(true);
scrollPane.setContent(imageView);
stage.setScene(new Scene(scrollPane, 400, 300));
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
堆栈跟踪：
java.lang.NullPointerException
at com.sun.prism.sw.SWGraphics.drawTexture(SWGraphics.java:686)
at com.sun.prism.sw.SWGraphics.drawTexture(SWGraphics.java:665)
at com.sun.prism.sw.SWGraphics.drawTexture(SWGraphics.java:648)
at com.sun.javafx.sg.prism.NGImageView.renderContent(NGImageView.java:123)
at com.sun.javafx.sg.prism.NGNode.doRender(NGNode.java:2067)
at com.sun.javafx.sg.prism.NGImageView.doRender(NGImageView.java:103)
at com.sun.javafx.sg.prism.NGNode.render(NGNode.java:1959)
at com.sun.javafx.sg.prism.NGGroup.renderContent(NGGroup.java:235)
at com.sun.javafx.sg.prism.NGRegion.renderContent(NGRegion.java:576)
at com.sun.javafx.sg.prism.NGNode.doRender(NGNode.java:2067)
at com.sun.javafx.sg.prism.NGNode.render(NGNode.java:1959)
at com.sun.javafx.sg.prism.NGGroup.renderContent(NGGroup.java:235)
at com.sun.javafx.sg.prism.NGRegion.renderContent(NGRegion.java:576)
at com.sun.javafx.sg.prism.NGNode.renderForClip(NGNode.java:2308)
at com.sun.javafx.sg.prism.NGNode.renderRectClip(NGNode.java:2202)
at com.sun.javafx.sg.prism.NGNode.renderClip(NGNode.java:2228)
at com.sun.javafx.sg.prism.CacheFilter.impl_renderNodeToCache(CacheFilter.java:663)
at com.sun.javafx.sg.prism.CacheFilter.render(CacheFilter.java:567)
at com.sun.javafx.sg.prism.NGNode.renderCached(NGNode.java:2372)
at com.sun.javafx.sg.prism.NGNode.doRender(NGNode.java:2058)
at com.sun.javafx.sg.prism.NGNode.render(NGNode.java:1959)
at com.sun.javafx.sg.prism.NGGroup.renderContent(NGGroup.java:235)
at com.sun.javafx.sg.prism.NGRegion.renderContent(NGRegion.java:576)
at com.sun.javafx.sg.prism.NGNode.doRender(NGNode.java:2067)
at com.sun.javafx.sg.prism.NGNode.render(NGNode.java:1959)
at com.sun.javafx.tk.quantum.ViewPainter.doPaint(ViewPainter.java:474)
at com.sun.javafx.tk.quantum.ViewPainter.paintImpl(ViewPainter.java:327)
at com.sun.javafx.tk.quantum.UploadingPainter.run(UploadingPainter.java:135)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.runAndReset(FutureTask.java:308)
at com.sun.javafx.tk.RenderJob.run(RenderJob.java:58)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at com.sun.javafx.tk.quantum.QuantumRenderer$PipelineRunnable.run(QuantumRenderer.java:125)
at java.lang.Thread.run(Thread.java:745)
