Im working on a school project and i'm trying to check in GWT if a textbox i create is empty or not. I have done the exact same thing on another project and there it worked fine. i have searched for the answer here and on google but couldn't find any answer.
voornaamTB = new TextBox();
voornaamTB.setText(null);
ok.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
if (voornaamTB != null) {
System.out.println("not empty");
} else {
System.out.println("empty");
}
}
});
Something like:
if(!voornaamTB.getText().isEmpty()) { ...
will work. You're currently testing to see whether the TextBox itself is null, which it isn't as you initialized it on the first line.
You probably don't need the setText(null) after immediately creating it.
Your object is not empty, so you can get only not empty. try this
voornaamTB = new TextBox();
voornaamTB.setText(null);
ok.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
if (voornaamTB.getText() != null) {
System.out.println("not empty");
} else {
System.out.println("empty");
}
}
});
Related
For a quite simple element
public static class ToolHtml extends Anchor {
private Long toolId;
public ToolHtml(ToolDetails toolDetails) {
this.toolId = toolDetails.getToolId();
this.setText(toolDetails.getName());
Style style = this.getElement().getStyle();
style.setColor("orange");
this.getElement().setId(DOM.createUniqueId());
}
public Long getToolId() {
return this.toolId;
}
}
I am trying to add some event handlers. I am interested in the DragStartEvent but not even the ClickEvent seems to work and I simply can't figure out why:
public void addOfferItem(ToolHtml toolHtml) {
Set<ToolHtml> toolHtmlSet = this.toolIdToToolHtml.get(toolHtml.getToolId());
if (toolHtmlSet == null) {
toolHtmlSet = new HashSet<>();
this.toolIdToToolHtml.put(toolHtml.getToolId(), toolHtmlSet);
}
toolHtml.getElement().setAttribute("contenteditable", "false");
toolHtml.getElement().setAttribute("draggable", "true");
toolHtml.addBitlessDomHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent event) {
LOGGER.fine("Click");
LOGGER.fine("Click");
LOGGER.fine("Click");
}
}, ClickEvent.getType());
toolHtml.addDomHandler((DragStartEvent event) -> {
LOGGER.fine("HANDLER DRAG START");
},
DragStartEvent.getType());
toolHtml.addDomHandler((DragStartEvent event) -> {
LOGGER.fine("DOM DRAG START");
},
DragStartEvent.getType());
toolHtml.addBitlessDomHandler((DragStartEvent event) -> {
LOGGER.fine("DRAG START");
},
DragStartEvent.getType());
toolHtmlSet.add(toolHtml);
// Attach/append to DOM
this.getElement().appendChild(toolHtml.getElement());
}
Does anybody know what the issue is here?
You append an element, not a Widget to which your handlers have been attached. You need to add a widget to a widget for all the functionality to work.
NB: Instead of toolHtml.addBitlessDomHandler you need to use
toolHtml.addClickHandler
So I have implemented a very simple drag and drop file upload widget. Basically my widget is a vertical panel with a couple of labels and a button inside. The user can either drag file into vertical panel or click button and browse for file.
My problem is that when I drag a file into the vertical panel it fires the DragLeaveEvent every time I drag the item over the space that the labels or button occupies. I want it to know that the item is in the vertical panel even when it is on top of the label or button. Im sure I am missing something simple. I provide the drag functionality by adding these dom handlers to the vertical panel:
addDomHandler(new DragEnterHandler() {
#Override
public void onDragEnter(DragEnterEvent event) {
System.out.println("drag enter");
highlight(true);
}
}, DragEnterEvent.getType());
addDomHandler(new DragLeaveHandler() {
#Override
public void onDragLeave(DragLeaveEvent event) {
System.out.println("drag leave");
highlight(false);
}
}, DragLeaveEvent.getType());
addDomHandler(new DragOverHandler() {
#Override
public void onDragOver(DragOverEvent event) {
}
}, DragOverEvent.getType());
addDomHandler(new DropHandler() {
#Override
public void onDrop(DropEvent event) {
System.out.println("drop");
// stop default behaviour
event.preventDefault();
event.stopPropagation();
// starts the fetching, reading and callbacks
if (fileUploadHandler != null) {
handleFiles(event.getDataTransfer(), fileUploadHandler);
}
highlight(false);
}
}, DropEvent.getType());
Check that the event target is a child (or grand child) of your panel, or in this case maybe rather whether the event target is exactly your panel's element:
if (verticalPanel.getElement().isOrHasChild(Node.as(event.getNativeEvent().getEventTarget()))) {
// within the panel (possibly on a child)
}
if (verticalPanel.getElement() == Node.as(event.getNativeEvent().getEventTarget())) {
// targetting exactly the panel (e.g. leaving the panel, not one of its children)
}
Through lots of research I have come to the only solution I could find. I set highlight to true in the dragover handler instead of drag enter.
panel.addDomHandler(new DragEnterHandler() {
#Override
public void onDragEnter(DragEnterEvent event) {
}
}, DragEnterEvent.getType());
panel.addDomHandler(new DragLeaveHandler() {
#Override
public void onDragLeave(DragLeaveEvent event) {
highlight(false);
}
}, DragLeaveEvent.getType());
panel.addDomHandler(new DragOverHandler() {
#Override
public void onDragOver(DragOverEvent event) {
highlight(true);
}
}, DragOverEvent.getType());
panel.addDomHandler(new DropHandler() {
#Override
public void onDrop(DropEvent event) {
// stop default behaviour
event.preventDefault();
event.stopPropagation();
// starts the fetching, reading and callbacks
handleFiles(event.getDataTransfer());
highlight(false);
}
}, DropEvent.getType());
I copy pasted your code, but also added a:
RootPanel.get().addHandler(dropHandler, DropEvent.getType());
My drophandler looks like this:
DropHandler dropHandler = new DropHandler() {
#Override
public void onDrop(DropEvent event) {
handleFiles(event.getDataTransfer(), new FileUploadHandler() {
#Override
public TYPE specifyFileType() {
return TYPE.BINARY;
}
#Override
public void handleFileContent(String fileName, String fileContent) {
// do stuff with filename and content
}
#Override
public boolean checkFileName(String fileName) {
return true;
}
});
event.preventDefault();
event.stopPropagation();
}
};
and the file-upload interface:
public interface FileUploadHandler {
static public enum TYPE {
TEXT, BINARY, DATAURL
};
// check the filename and extension and return true if you are happy with
// proceeding
// returnning false will prevent the file from being read
boolean checkFileName(String fileName);
// tell the method to use to read this file
TYPE specifyFileType();
// do your stuff here, eg upload to a server
void handleFileContent(String fileName, String fileContent);
}
and the handle files func: (note you will have to change classpath to the FileUploadHandler-interface)
// native method to make use of the HTML5 file API functionality
private final native void handleFiles(JavaScriptObject dataTransfer, FileUploadHandler fileUploadHandler) /*-{
var files = dataTransfer.files;
var i;
var file;
var reader = new FileReader();
for (i = 0; i < files.length; i++) {
file = files[i];
if (fileUploadHandler.#<classpath_to>.FileUploadHandler::checkFileName(Ljava/lang/String;)(file.name)) {
var type = fileUploadHandler.#<classpath_to>.FileUploadHandler::specifyFileType()();
reader.onload = function(e) {
fileUploadHandler.#<classpath_to>.FileUploadHandler::handleFileContent(Ljava/lang/String;Ljava/lang/String;)(file.name, e.target.result);
}
if (type == "TEXT") {
reader.readAsText(file);
} else if (type == "BINARY") {
reader.readAsBinaryString(file);
} else if (type == "DATAURL") {
reader.readAsDataURL(file);
// not supported
} else if (type == "ARRAYBUFFER") {
reader.readAsArrayBuffer(file);
} else {
}
}
}
}-*/;
I want to disable the anchor link event when it clicked one time. I used anchor.setenabled(false) but nothing happend. When I click the same button again the event e is true. I want false at that time.
public void onCellClick(GridPanel grid, int rowIndex, int colindex,EventObject e)
{
if(rowIndex==0 && colindex==2){
tomcatHandler = "Start";
anchorStart.setEnabled(false);
}else if(rowIndex==0 && colindex==3){
tomcatHandler = "Stop";
****anchorStop.setEnabled(false);
anchorStart.setEnabled(false);
anchorRestart.setEnabled(true);****
}else if(rowIndex==0 &&colindex==4){
tomcatHandler = "Restart";
anchorRestart.setEnabled(false);
}
AdminService.Util.getInstance().tomcat(tomcatHandler,new AsyncCallback<String>() {
#Override
public void onSuccess(String result) {
imageChangeEvent(result);
}
#Override
public void onFailure(Throwable caught) {
}
});}
Anchors in GWT have always had a problem with setEnabled() because HTML doesn't support such a property. A quick workaround is to create a new widget that subclasses GWT's Anchor, adding the following override:
#Override
public void onBrowserEvent(Event event) {
switch (DOM.eventGetType(event)) {
case Event.ONDBLCLICK:
case Event.ONFOCUS:
case Event.ONCLICK:
if (!isEnabled()) {
return;
}
break;
}
super.onBrowserEvent(event);
}
This disables the passing of the browser event to GWT's Anchor class (summarily disabling all related handlers) when the link is double clicked, focused or clicked and is in a disabled state.
Source
It doesn't seem to actually disable the anchor, but it does retain the status that has been set with anchor.setEnabled(), so just test that within your handler e.g.
myAnchor.addClickHandler(new ClickHandler() {
#Override
public void onClick(ClickEvent evt) {
// write to filter and then call reload
if (((Anchor) evt.getSource()).isEnabled()) {
//do stuff
}
}
});
I wrote an Eclipse Plugin that basically allow a programmer to select a Java source from the Project Explorer and by selecting the corresponding DropDown menu option it will creates an interface .java file based on the one selected.
Everything works fine, but now I need to program the update part of the job.
The update requierement is simple, I need to listen for changes and identify that the sources that have the interface generated have been modified and recreate the interface file.
To do this I wrote a class that implements IResourceChangeListener interface.
That class looks like:
public class DTOChangeListener implements IResourceChangeListener {
private List<UpdatedUnit> updatedUnits;
public DTOChangeListener() {
super();
this.updatedUnits=new ArrayList<UpdatedUnit>();
}
#Override
public void resourceChanged(IResourceChangeEvent event) {
try{
if(event.getType() == IResourceChangeEvent.POST_CHANGE){
event.getDelta().accept(this.buildVisitor());
}
}catch(CoreException ex){
ex.printStackTrace();
}
}
protected IResourceDeltaVisitor buildVisitor(){
IResourceDeltaVisitor result=new IResourceDeltaVisitor() {
#Override
public boolean visit(IResourceDelta resDelta) throws CoreException {
String resName=resDelta.getResource().getName();
if(resName==null || resName.equals("")){
return true;
}
String[] splits=resName.split("\\.");
String name = splits[0];
if(name.contains("PropertyAccess")){
return false;
}
String interfaceName=name + "PropertyAccess";
String interfaceFile=interfaceName + ".java";
IResource res=resDelta.getResource();
if((res instanceof IFolder) || (res instanceof IProject)){
// Avoid Folder & Project Nodes
return true;
}
IProject project=res.getProject();
if(project!=null){
if(project.isNatureEnabled("org.eclipse.jdt.core.javanature")){
IJavaElement element=JavaCore.create(res);
if(element instanceof ICompilationUnit){
ICompilationUnit unit=(ICompilationUnit)element;
IPath path=res.getProjectRelativePath().removeLastSegments(1);
IResource propertyAccess=project.findMember(path.append(interfaceFile));
if(propertyAccess!=null){
UpdatedUnit updatedUnit=new UpdatedUnit(project, path, unit);
updatedUnits.add(updatedUnit);
return false;
}
}
}
}
return true;
}
};
return result;
}
public List<UpdatedUnit> getUpdatedUnits() {
return updatedUnits;
}
}
I add the Listener to the Workspace, now the question I have is:
How can I know when the updatedUnits List is completed in order to proccess the list with my own code?
One posible answer to this question would be, don't worry, the:
event.getData().accept(this.buildVisitor());
will block until proccessing of the visitor finish.
but at least is not documented like it would.
Any ideas would be appreciated.
Thanks in Advance.
Daniel
Unless it's documented to not block, it blocks.
I would like to add more tabs to the tab panel upon receiving a reponse from a servelet.. the problem is that It only adds the last one and not the the others see part of the code below. It seems like it is only adding the last panel "Time Reports" but not the other two
Thank you
btnLogin.addClickListener(new ClickListener() {
public void onClick(Widget sender) {
if(getLoginResult())
{
HorizontalPanel temp = new HorizontalPanel();
panel.add(temp, "Add Hours");
panel.add(temp, "Time Sheets");
panel.add(temp, "Time Reports");
}
}
});
RootPanel.get().add(panel);
}
private boolean getLoginResult() {
AsyncCallback callback = new AsyncCallback() {
public void onSuccess(Object result) {
isAuthenticated = true;
}
public void onFailure(Throwable caught) {
Window.alert("Error when invoking the pageable data service :" + caught.getMessage());
isAuthenticated = false;
}
};
timesheetLoginServlet.isAuthenticated("1","rapidjava", callback);
return isAuthenticated;
}
}
You can add any widget to its parent only once. Change the temp to temp1, temp2 and temp3