MvxListView and scrolling down - xamarin.android

I'm using an MvxListView that is bound to an observablecollection to display chat messages. I found a way that the listview always scrolls down to the bottom with these 2 attributes:
android:stackFromBottom="true"
android:transcriptMode="alwaysScroll"
This works great when I add a message to the observablecollection via a command (when I send a message myself), but when I receive a message (via signalr) via the viewmodel and then add the message exactly the same way to the observablecollection, the ListView is updated but it doesn't scroll down. When I scroll down manually the message is there, it just doesn't scroll down automatically. I'm thinking this might have something to do with the message arriving via signalr, because it's an async callback.
I tried to manually force the listview to scroll down in an MvxAdapter like this:
public override void NotifyDataSetChanged()
{
base.NotifyDataSetChanged();
((FragmentActivity)_context).RunOnUiThread(() =>
{
_list.SetSelection(this.Count-1);
});
}
and then call that explicitly when a message arrives but that doesn't do anything either.
Help?

Just saw this answer from Slodge:
Advice on where and when to use ObservableCollection in MvvmCross
The UI updates must be done synchronously. And thinking about it, it makes sense indeed. The answer for me was to use:
MvxMainThreadDispatcher.Instance.RequestMainThreadAction(() => {
// fill your collection in the viewmodel and do a propertychanged
});

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I'm trying to fire an event programmatically. My problem is that I have two SVG on two DIVs and I want to be able to change the border of the DIV I have clicked. To do that I thought to pass the DIV inside my classes and then trigger a click on it once I click on anything. (if there is a better way, please tell me)
I have the following code:
div = querySelector(divName);
svgElement = new svg.SvgSvgElement();
div.append(svgElement);
div.onClick.listen(_setBorders(1));
later I pass the svgElement to another class
ell.show(svgElement);
where show is
show(svg.SvgElement element) {
if (element.parent is DivElement){
_parentDiv= element.parent as DivElement;
element.children.add(_group);
}
}
_parentDiv is of course a DivElement, which I use for an internal onClick()
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window.console.info("onClick Ell");
_parentDiv.click();
}
I'm expecting to see the _setBorders(1); I defined with the main div, but it doesn't work. The weird thing is that when I check with the debugger set to the _parentDiv.click() I see that _parentDiv has the event correctly set.
I suppose click() doesn't work as I expected. Any Idea?
If you want that _setBorders(1) is called on click events you have to use :
div.onClick.listen((_) => _setBorders(1));

How do I make JQuery UI Slider update Meteor Collection (MongoDB) without disappearing

I have two Meteor.Collections in my app. One contains a bunch of "slider" objects, which define a title, max, min, base value, and step for each slider. Now, I have two problems. The first is making the sliders show up in the first place. I've tried to put the following code:
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$("#"+slider._id).slider({
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max:slider.max,
value:slider.base,
step:slider.step,
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in Meteor.startup, at the end of my client.js file, in a $(document).ready() block, and nothing seems to get it to work. When I paste it into the javascript console, however, it works. Anyways, that's my first problem.
My second problem is that whenever I slide the slider, the slider disappears. I can keep dragging the mouse around to change the value, but once I let go of the clicker, I can't change the value anymore. I've tried using the above way and calling a Meteor.method that changes it on the server side. It's the fact that I'm updating a collection that is published to the same client that makes the slider disappear. Anything short of that doesn't cause it to disappear. How should I deal with this?
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Have you already tried using the Template.preserve method? http://docs.meteor.com/#template_preserve

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I have a jQuery mobile button hooked up to an ajax POST. If the POST fails, the jQuery mobile button stays pressed instead of ``popping up". Any ideas?
It can be done easily.
Here a jsFiddle example made for one of my previous answers: http://jsfiddle.net/3PhKZ/7/
If you take a look there's this line of code:
$.mobile.activePage.find('.ui-btn-active').removeClass('ui-btn-active ui-focus');
It will try to find pressed button on a current active page, if it succeed it will remove 2 classes responsible for a button pressed state. Unfortunately pure CSS solution is impossible here. You can test this example, just comment top line and see what will happen.
One last thing selector $.mobile.activePage can only be used during the pagebeforeshow, pageshow, pagebeforechange, pagechange, pagebeforehide and pagehide page event so takes this into account.
In case you cant use this selector just replace it with a page id, like this:
$('#pageID').find('.ui-btn-active').removeClass('ui-btn-active ui-focus');
So your final code would look like this:
$.ajax( "example.php" )
.success(function() { doStuff(); })
.error(function() {
$('#pageID').find('.ui-btn-active').removeClass('ui-btn-active ui-focus');
})
Add an error clause to your AJAX handling which pops the button back.
$.ajax( "example.php" )
.success(function() { doStuff(); })
.error(function() { /*code to unpress button here*/ })
For those folks out there using "input" and not "anchors" as buttons. When using for instance "submit" and "reset" buttons and pressing them they remain as active, which is sometimes undesired depending on the actions performed when the buttons is clicked.
I am not sure if it is the expected behaviour, I have read that is a jQuery mobile bug, but the behavior is still present at least in jQM 1.3.2
An yes the trick is to remove the active class as stated however those get tricky because the class is not added to the input tag, i*t is added to a parent DIV* that is created by all of the ugly stuff around the "input" to style the button, that is why removing the active class when selecting the input doesn´t work.
By analyzing the HTML produced by jquery mobile a workaround is to:
remove the active class on the input parent instead of the actual input element.
$('.mybutton_class_or_ID').parent().removeClass('ui-btn-active');
I prefer this approach instead of clearing all the active classes across the whole page in case you want to be more selective with the class removal.

Handle changes to a big form. Alert before closing modal

I am currently working on a Customer Management application made in SmartGWT 2.0.
The Add Customer form is a fairly big one with multiple tabs and each tab has lot of fields. This form is opened in a modal window which have a save and a close button at the bottom.
Since this is a huge form, sometimes the rep accidentally hits Close without noticing that there is some information in one of the tabs.
We want to add some kind of alert when user tries to close the form after he has made changes to it.
I saw that there is ChangeHandler on text items which can flag a change which can be evaluated before firing the close event. However currently doing this for so many fields is a little bit cumbersome. Is there a way of achieving this on a DynamicForm level or even better on the Window level?
I am looking for a SmartGWT equivalent of this jquery code:
$("input:text, select, input:checkbox, input:radio, input:password").change(function(){
unloadRoutineFlag = true;
});
Take a closer look at this handler at the dynamicForm level.
addItemChangedHandler(ItemChangedHandler handler)
Handler fired when there is a changed() event fired on a FormItem
within this form.
Typically, when a formItem fires the changed() event, the form gets notified. Let us know if this works.

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I have a basic JQM page which displays a left side sliding menu when swiping (like the facebook mobile app). It worked fine until I started using scrollview (to properly keep the header fixed). The swipe event is not triggered when I swipe over my page content (it still works if I swipe on the header).
$('.ui-page-active').live("swiperight", function() {
if (!menuStatus) {
showMenu();
}
});
Does anyone has any idea on how to make it work?
Cheers!
I think you might find that the event is consumed in the scrollview control. You can override the javascript handler against that control to allow it to keep bubbling.
To override the function you can use this technique: Overriding a JavaScript function while referencing the original
Having a quick look at the file, it looks like this method could hold clues as to what you want:
_handleDragMove: function(e, ex, ey)
specifically:
var svdir = this.options.direction;
if (!this._directionLock)
I was using the version of scrollview shown here: http://jquerymobile.com/test/experiments/scrollview/scrollview-nested.html

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