Vaadin add/remove components with buttonclick - dynamic

how to check if an component is already in the layout?
I have an 4x4 gridlayout
with some buttons
one button is to show an datagrid
one to show inputfields
what I try to do is
MenuBar.Command tablecommand = new MenuBar.Command() {
public void menuSelected(MenuItem selectedItem) {
output.setValue("clean components");
layout2.removeComponent(name);
layout2.removeComponent(name2);
layout2.removeComponent(button);
layout2.removeComponent(cp);
//layout2.removeComponent(grid);
//if layout2 !contains grid
layout2.addComponent(grid,1,2);
}
};
without check I get an exception
java.lang.IllegalArgumentException: Component is already in the container
at com.vaadin.ui.GridLayout.addComponent
when I click on the showgrid button the second time
the only thing I can find is ".equals(obj)"

You can look if the component has a parent.
If yes, then it's already in place somewhere.
https://vaadin.com/api/com/vaadin/ui/Component.html#getParent--

Related

Eclipse plugin development - How to add Radio buttons in WizardNewFileCreationPage

I am using WizardNewFileCreationPage to create a New File
public void addPages() {
mainPage = new WizardNewFileCreationPage("FILE", getSelection());
mainPage.setTitle("New File");
mainPage.setDescription("Add new file");
addPage(mainPage);
}
I want to add some Radio Buttons to it representing file extensions in this wizard so that users can select one of them as a file extension.
The WizardNewFileCreationPage is not meant to be extended with custom controls. From its JavaDoc:
Subclasses may override
getInitialContents
getNewFileLabel
Subclasses may extend
handleEvent
If you still want to add the radio buttons 'at your own risk', you can try to override createAdvancedControls and append you controls to the parent after calling super.
protected void createAdvancedControls(Composite parent) {
super.createAdvancedControls( parent );
Button radioButton = new Button( parent, SWT.RADIO );
// ...
}
Note that the layout of parent (currently) is a single-columned GridLayout, set the layout data accordingly.

Dojo:how to find if the widget has focus in dojo

how do I find out if my custom widget has focus in Dojo?
i have dojo editor i wnat to know if the editor has already focus or not?
you can use the module dijit/focus to find out the focus
FROM DOJO DOCS
Tracking active widgets
At any point in time there is a set of (for lack of a better word)
“active” or “focused” widgets, meaning the currently focused widget
and that widget’s ancestors. “Ancestor” can mean either DOM ancestor
(ex: TextBox –> Form), or a logical parent-child relationship (ex:
TooltipDialog –> DropDownButton).
For example, if focus is on a TextBox inside a TabContainer inside a
TooltipDialog triggered by a DropDownButton, the stack would be
TextBox –> ContentPane –> TabContainer –> TooltipDialog –>
DropDownButton.
The activeStack[] parameter indicates this set of widgets, and an app
can monitor changes to activeStack[] by:
require([ "dijit/focus" ], function(focusUtil){
focusUtil.watch("activeStack", function(name, oldValue, newValue){
console.log("Focused widget + ancestors: ", newValue.join(", "));
});
});
the question in title has a different answer than the one in the descriptions.
there are two ways achieving the question in the title, by using dojo's focusUtil ("dijit/focus"). both ways give you something that you could find the widget using it and the dijit's registry ("dijit/registry").
focusUtil.curNode: gives you the DOM Node that currently has the focus. the function below, you could get the widget reference.
function getWidgetByNode(node){
var result;
while (!result && node){
result = registry.byNode(node);
if (node.parentElement)
node = node.parentElement;
else
node = null;
}
return result;
}
var focusedWidget = getWidgetByNode(focusUtil.curNode)
focusUtil.activeStack: gives you an array of the widgets (parent to child) that has the focus. so the last item in the array is the direct widget which has the focus. index values are widget ids, so you should get the widget by the following code
var focusedWidgetId = focusUtil.activeStack[focusUtil.activeStack.length-1];
var focusedWidget = registry.byId(focusedWidgetId);
now if you want to know if the currently focused widget is some specific one, it depends on what you have in hands from that specific widget:
widget itself: like the return values of above samples. now you have to compare if these are the same thing. you can not compare two widget objects using the == operator. you could compare their ids like this:
myWidget.id == focusedWidget.id
widget's id: this way you just easily get the id of the current node from focusUtil and compare it with the id you have liek this:
myWidgetId == focusedWidgetId
references:
http://dojotoolkit.org/reference-guide/1.9/dijit/focus.html
http://dojotoolkit.org/reference-guide/1.9/dijit/registry.html
require([ "dijit/focus" ], function(focusUtil){
var activeElement = focusUtil.curNode; // returns null if there is no focused element
});
check blow url here you can see some examples
http://dojotoolkit.org/reference-guide/1.8/dijit/focus.html#dijit-focus
a) For dojo 1.6: call dijit.getFocus(). This will return an object containing the currently focused dom node, among other things (selected text, etc.). To get the corresponding widget, simply do:
var activeElement = dijit.getEnclosingWidget(dijit.getFocus().node);
This is the full reference for dijit.getFocus(), from the source code:
// summary:
// Called as getFocus(), this returns an Object showing the current focus
// and selected text.
//
// Called as getFocus(widget), where widget is a (widget representing) a button
// that was just pressed, it returns where focus was before that button
// was pressed. (Pressing the button may have either shifted focus to the button,
// or removed focus altogether.) In this case the selected text is not returned,
// since it can't be accurately determined.
//
// menu: dijit._Widget or {domNode: DomNode} structure
// The button that was just pressed. If focus has disappeared or moved
// to this button, returns the previous focus. In this case the bookmark
// information is already lost, and null is returned.
//
// openedForWindow:
// iframe in which menu was opened
//
// returns:
// A handle to restore focus/selection, to be passed to `dijit.focus`.
b) For dojo 1.7 and up, use dijit/focus:
require([ "dijit/focus" ], function(focusUtil) {
var activeElement = focusUtil.curNode; // returns null if there is no focused element
});

Nested Grid in GWT

I need to develop a control which is similar to the Nested Grid in the Smart GWT.
User will be having a column for expansion images, when user clicking on the image in a particular row, a sub grid has to be opened there itself. Here all remaining rows needs to move down.
How can i achieve that functionality? Can anybody give me some clues so that i can proceed.
I have already a grid which is a celltable with custom header(with search functionality implemented).
Thanks,
Saritha.
Create your nested widget (myNestedWidget) that you want to show. It should have a CSS style "position: absolute", unless your grid is added to the LayoutPanel (or similar), in which case you can position your widget directly. Let's call the parent widget of your grid gridParentWidget.
In your CellTable add the following handler:
myTable.addCellPreviewHandler(new Handler<myObject>() {
#Override
public void onCellPreview(CellPreviewEvent<myObject> event) {
if ("click".equals(event.getNativeEvent().getType())) {
if (event.getColumn() == 0) {
int top = myTable.getRowElement(event.getIndex()).getAbsoluteBottom();
int left = myTable.getRowElement(event.getIndex()).getAbsoluteLeft();
myNestedWidget.getElement().getStyle().setTop(top, Unit.PX);
myNestedWidget.getElement().getStyle().setLeft(left, Unit.PX);
gridParentWidget.add(myNestedWidget);
Scheduler.get().scheduleDeferred(new ScheduledCommand() {
#Override
public void execute() {
int height = myNestedWidget.getOffsetHeight();
myTable.getRowElement(event.getIndex()).getStyle().setHeight(height + "px");
]
});
}
}
});
}
This is obviously an outline of the solution. The details of the implementation may vary slightly depending on which widgets you use for your parent widget and your nested widget. If you change z-indexes somewhere, you have to take it into account too. You also need to make sure that your nested widget fits into the width of your grid, or you'll need to wrap it in a ScrollPanel and set a width to it explicitly.

DojoX Mobile ListItem load HTML via AJAX and then remove from DOM

Let's say in a view I have a DojoX Mobile ListItem that is pulling an HTML view fragment into the DOM via AJAX and then transitioning to that view. Assume this is all working fine.
Now, I go back to the initial view that had that ListItem on it and click some other button that destroys that view node from the DOM. If I now click on that ListItem that previously loaded that view node into the DOM (which has now been removed), it will try to transition to a view that doesn't exist. It doesn't know that it has been removed.
Is there some type of way to tell a ListItem that it needs to fetch the HTML again because what was previously fetched no longer exists? I am not seeing anything about doing this in any documentation anywhere. I don't think a code sample is really necessary here, but I can provide a minimal one if necessary.
I went a different route and left the view exist in the DOM, and simply made a function that clears all sensitive data out of the view.
Okay, in this case, i guess you could hook the onShow function of your ListItem container(or any other onchange event). Create a listener for said handle to evaluate if your item needs reloading. Following is under the assumtion that it is the item.onclick contents showing - and not the label of your item which contains these informations
Or better yet, do all this during initialization so that your ListItem container will be an extended with custom onClick code.
Seems simple but may introduce some quirks, where/when/if you programatically change to this item, however here goes:
function checkItem() {
// figure out if DOM is present and if it should be
if( isLoggedIn() ) {
this.getChildren().forEach(function(listitem) {
if( dojo.query("#ID_TO_LOOK_FOR", listitem.domNode).length == 0 ) {
// this references the listItem, refresh contents.
// Note: this expects the listitem to be stateful, have no testing environment at time being but it should be
listitem.set("url", listitem.url);
}
});
}
}
Preferably, set this in your construct of the container for your ListItems
var listItemParent = new dojox.mobile.RoundRectList({
onShow : checkItem,
...
});
Or create listener
var listItemParent = dijit.byId('itemRegistryId');
// override onClick - calling inheritance chain once done
dojo.connect(listItemParent, "onClick", listItemParent, checkItem);

Windows Phone 7 Control Caching - 'Element is already the child of another element'

I'm trying to speed up my windows phone 7 page load times. I have a 'static' page that has a dynamically created in a Panorama control - static meaning that the content never changes.
On the first load I look at my config file, create the individual PanoramaItem controls and add them to the main Panorama control. I'm trying to keep a List in a static place so that the initial creation would only happen once and I could just add a fully rendered version to my Panorama control when the page was rendered.
Works fine on first load, but when I try to add the cached PanoramaItems to the Panorama control I get the message "Element is already the child of another element". This makes sense since I already added before. But I can see a way to disconnect the PanoramaItems with the first Panorama control...
I could be going about the control caching thing all wrong as well... Let me know if there's another way to do this.
You can use Panorama.Items.Remove(pivotItem) for this
As an example
With the following page fields
PanoramaItem pi;
bool blahShown = false;
On the press of this button, the control is first instantiated and displayed and on subsequent presses removed and readded without instantiation.
private void button1_Click(object sender, RoutedEventArgs e)
{
if (pi == null) {
pi = new PanoramaItem();
pi.Header = "blah";
}
if (blahShown) {
Pano.Items.Remove(pi);
blahShown = false;
} else {
Pano.Items.Add(pi);
blahShown = true;
}
}