#43 PNGImage (GWT-WL 0.2.0) Bug in GWT 1.5RC1

[Anonymous]

Error occurred while initializing PNGImage:

[ERROR] Unable to load module entry point class org.example.Main (see associated exception for details)
java.lang.AssertionError: Element may only be set once
at com.google.gwt.user.client.ui.UIObject.setElement(UIObject.java:802)
at org.gwtwidgets.client.ui.PNGImage.<init>(PNGImage.java:48)
at org.gwtwidgets.client.ui.LightBox.show(LightBox.java:85)
...

Because of this error LightBox.show() also generates error.

[Nobody/Anonymous]

Logged In: NO

Agree, please fix this.

[Nobody/Anonymous]

Logged In: NO

+1

[Nobody/Anonymous]

Logged In: NO

+1
Does someone look into it?

[Nobody/Anonymous]

Please solve this problem or suggest a workaround, it is an annoying situation not being able to use LightBox anymore...

[Nobody/Anonymous]

looks like the only workaround is to:

1. move PNGImage to the com.google.gwt.user.client.ui package
2. use replaceElement instead of setElement in the PNGImage constructor

[Nobody/Anonymous]

I was able to get thsi working by rewriting PNGImage to be a Composite:

public class PNGImage extends Composite {
private PNGImageImpl impl;
private Widget widget;
public PNGImage(String url, int width, int height) {
impl = (PNGImageImpl) GWT.create(PNGImageImpl.class);
impl.createImage(url,height,width);
initWidget(impl.getWidget());
sinkEvents(Event.ONCLICK | Event.MOUSEEVENTS | Event.ONLOAD | Event.ONER
ROR);
}
public String getUrl() {
return impl.getUrl();
}

/**
* Should not be used. Throws RuntimeException
*/
public void setUrl (String url) {
throw new RuntimeException("Not allowed to set url for a PNG image");
}

}

and changing both Impls:

public class PNGImageImpl {
protected Widget img = null;

public void createImage(String url, int height, int width) {
if (img == null) {
img = new Image(url);
}
DOM.setElementPropertyInt(img.getElement(), "width", width);
DOM.setElementPropertyInt(img.getElement(), "height", height);
}

public String getUrl() {
return DOM.getElementProperty(img.getElement(), "src");
}

public Widget getWidget() {
return img;
}
}

public class PNGImageImplIE6 extends PNGImageImpl {
private String url;

public void createImage(String url, int height, int width) {
this.url = url;

boolean isPNG = url.endsWith(".png") || url.endsWith(".PNG");

if (img == null) {
if (isPNG) {
final Element div = DOM.createDiv();
DOM.setInnerHTML(div, "<span style=\"display:inline-block;wi
dth:" +
width + "px;height:" + height +
"px;filter:progid:DXImageTransform.Microsoft.Alp
haImageLoader(src='" +
url + "', sizingMethod='scale')\"></span>");
img = new Widget(){
{
setElement(DOM.getFirstChild(div));
}
};

} else {
super.createImage(url, height, width);
}
}

}

public String getUrl() {
return url;
}
}

Unfortunately, this breaks ImageButton and ToggleButton, but I wasn't using those.

Hope this helps.
Dan