WebViewPreview: fixed occasional JSException: TypeError: null is not an object (evaluating 'document.body.scrollHeight')

DevCharly · DevCharly · commit 270a95575370 · 2016-12-13T11:25:44.000+01:00
diff --git a/src/main/java/org/markdownwriterfx/preview/WebViewPreview.java b/src/main/java/org/markdownwriterfx/preview/WebViewPreview.java
@@ -103,7 +103,8 @@ public void update(Renderer renderer, Path path) {
 	@Override
 	public void scrollY(double value) {
 		webView.getEngine().executeScript(
-			"window.scrollTo(0, (document.body.scrollHeight - window.innerHeight) * "+value+");");
+			"if(document.body != null)" +
+			"  window.scrollTo(0, (document.body.scrollHeight - window.innerHeight) * "+value+");");
 	}
 
 	@Override

Original file line number	Diff line number	Diff line change
`@@ -103,7 +103,8 @@ public void update(Renderer renderer, Path path) {`
`103`	`103`	`@Override`
`104`	`104`	`public void scrollY(double value) {`
`105`	`105`	`webView.getEngine().executeScript(`
`106`		`- "window.scrollTo(0, (document.body.scrollHeight - window.innerHeight) * "+value+");");`
	`106`	`+ "if(document.body != null)" +`
	`107`	`+ " window.scrollTo(0, (document.body.scrollHeight - window.innerHeight) * "+value+");");`
`107`	`108`	`}`
`108`	`109`
`109`	`110`	`@Override`