The question is more or less what the title says: I have a CustomView class that implements the View interface (Thus, the enter function, which takes a ViewChangeEvent parameter).
I'm trying to identify when the view change is triggered by an user clicking the browser "back" button (as opossite as an user clicking a link to enter that view on the application), but I've been unable to get where (if it is possible) get this information.
Am I looking into the right component? Should I look anywhere else? There's any way to find about this?
EDIT: Huh, maybe I could add a custom parameter in every, single, call to the ViewChange so I can "mark" the "normal clicks" and identify "go back/go forward" by the absence of it, but it seems like a dirty, ugly trick...
Ok, this will go with a bit of story, so:
I found a way to identify the "user has pressed the back button" on Vaadin, as it seems the framework manages the location change through the Page.updateLocation(String location, boolean fireEvents) function. I haven't, though, being able to modify the location parameter (This could be either due Vaadin's own architecture or due my own application specifics), so I've ended up using the function "changeVariables" on the UI class (on a inherited, own, UI class) to send a new ViewChangedEvent.
It feels a bit like a hack, but as I said, I haven't been able to make it better.
Going a bit into the specifics of my problem, in case someone finds it useful, I needed to identify somehow that the user was "coming back" from a different view through the "back" browser button or the "backspace" key, so I decided to used a flag on the params to indicate that the view is "retornable." This flag will have two values: "retornable" (as in "I just got into the view") and "returning" (as in "I just came back to a retornable view"). For those who will only look at code, this is what the url will show:
#!viewName/retflag=retornable&otherStuff=maybe
#!viewName/retflag=returning&otherStuff=perhaps
As I said, my "entry point" is located on "OurCustomUI" which extends UI, and had this little function:
#Override
public void changeVariables(Object source, Map<String, Object> variables) {
super.changeVariables(source, variables);
}
Here, the idea is getting the "location" variable from the, huh, variables Map and update it. It would be something like this:
myServer.myCompany.com/myApp/#viewName/retflag=retornable
So the code would be finding the "retflag" value, changing it to "returning", creating the ViewChangedEvent and firing it. I need to keep the super.changeVariables() call at the beginning because reasons, but it seems to work just fine as it is.
Related
Simplifying, I have this structure
Form {
tab=Container(BoxLayout.y());
other stuff
}
The Form is not scrollable (and it is not supposed to be), tab is.
At some point I want to redraw the Form to keep it up to date with some new info added, and I do that creating a new one and showing it.
But I want to scroll down the Container tab to its predecessor's Y-coordinate.
I can easily save the Y coordinate in a static variable using
scrolledToY=tab.getScrollY();
But I can't find a way to set it back when I create the new form.
setScrollY seems to be protected, and indeed if I try to run the program using it, I get an error
error: setScrollY(int) has protected access in Component
tab.setScrollY(scrolledToY);
What is the correct function to use, instead?
Thanks.
You can use scrollRectToVisible().
FYI you can just modify the container and call revalidate to update the UI. This will prevent a nasty refresh problem you might experience. Also check out InfiniteContainer which might be what you're really looking for.
I have been digging around in the search view source code for quite sometime now trying to understand how exactly does the search view even have a user interface to be rendered. First of all here is the source code:
SearchView source code
So what I don't understand is how does the user interface element of the search view even get rendered when the search view doesn't even have any onDraw() method. All that I can see is responsible for the display element is a bunch of view at the start which are in the constructor, the SearchView gets a reference to and change the background and set the image of these view. If all that I can see was done is getting references to some views and changing the background as well as the image without having it within the proper view hierarchy then how exactly does it even get rendered?
I understand what you are probably wondering why do I even need to understand this. Well I want to understand this so I can create my own custom search view. Since I only need like 2 function on my search view I figure it would be a lot better to make one that suits my need instead of the thousand of lines of code in the source one. Plus, I want to create one that I know I will understand how to use not the complex default one.
I've one seen on an application for iPhone an interesting idea which consists of showing a list of options when we click on an area for text edition. For example, imagine I have a field called "City" (EditText) which I am suposed to enter the name of the city. When clicking on the EditText, a list automatically shows up with a few city suggestions (e.g. defined by the programmer) which can be selected. If the user doesn't like the suggestions, he writes the city himself and this city can be saved for this list for future.
I want to programme this on my App for android. I need that, when clicking on the EditText for introducing the data, a list automatically shows up with some suggestions defined by me (Programmer). However, I don't know how this can be done. I've googled but maybe it's hard to find the correct keywords to find a similar topic.
The idea is that the user should use the names already written in the list in 90% of the time and just write himself the new ones when it's necessary. Something like a dropdown list but with possibility of writing new stuff instantly without specific option.
How can this be achieved?
You Need Something Like View in android Named as
AutoTextComplete
Examples How to use this :
help
Best of luck
You can consider focus changed listener for Edittext,
when focus is gained you can show a context menu to choose data from.
What is the purpose of onSearchRequested()? I am referring to here: http://developer.android.com/reference/android/app/Activity.html#onSearchRequested%28%29
The following is stated: "You can override this function to force global search, e.g. in response to a dedicated search key, or to block search entirely (by simply returning false)." Specifically, what does the bolded piece mean? Does it not mean that we are able to disable this button? I just had a heated discussion at: Android - How to disable Search button, how to implement onSearchRequested()?
As you can see, Phil is suggesting that I have to go the other route. My questions are: can JUST this function be used to disable the search button completely? Can just this function be used without having to disable this button from the dialog builder? What did google meant with the above quoted statement? Thank you for your time.
You should be able to disable the search button using it, i would think google mean that you can block someone trying to search from within your app( IE skipping a progress dialog)
but since most android phones don't come with search buttons anymore, its not a very used function.
and yes you should be able to disable it on the fly without going through the dialog builder.
Swift
I just started yesterday using GWT, so maybe I'm not using the proper mechanism to solve that problem. So, I will try to explain exactly what I'm trying to do (with a simple problem) and 2 solutions I came up with to address that problem.
Problem:
Remember an index that can be updated via other widgets. Let's use focus to represent it.
[button 1]
[button 2] [button A]
[button 3]
The buttons [1..3] and [A] are not in the same class and need to find the element using the id using the DOM. The reason is that those 2 views needs to be orthogonal.
We can use up/down key to move the focus from button 1 to 3.
If we are on the buttons [1..3] and press right, we go to button A.
If we are on the button A and press left, we go to button previously focused.
What we want to do is save or set the focus index when pressing right.
Solution 1: Global variables
I'm not usually fond of global variables, but in some case it's handy. By using, for instance, a dictionary (Dictionary.getDictionary) defined globally in the javascript, I could save the current index in it using the "Focus Event" in that case.
So, in the key press event, when left would be fired, I would just read the value in the dictionary.
I haven't tested yet, but I think it should work.
Solution 2: Set the value with the Element
Element element = DOM.getElementById("button id A");
element.<setFocusLeftKey>("button id [1..3]");
Here what I would like to achieve is just in the "onFocus" Event, I would simply set the value of that button.
So is it possible to cast/find the object with the Element? I think that if there is no easy way, it's probably because it's not recommended.
Is there a simpler way/other method to achieve that?
So, any thought or solutions?
Thanks in advance.
P.S. I haven't found a better title for that, so if any suggestion, just put it in the comments and I'll update it.
Using ID is definitely not the suggested way to do this in GWT. You say you need this mechanism to keep your views orthogonal to one another. This is noble, but in GWT you would achieve by using another resource (an EventBus, implemented in SimpleEventBus) that hides the different components from one another. In fact, I would argue that looking up the element by ID strongly couples the two views and is smelly.
Armed your EventBus you simply create and fire custom events that let the views (or, better, their presenters) communcate with one another. For example here you could have: NavigateRightFromButtonsEvent and NavigagteLeftFromButtonA event.
However, depending on the size of your app (or as a first experiment) you could decide to couple your two views. In this case simply pass the view for the button list into the one for button A and vice-versa. This is not really worse than relying on a global ID.
No matter which mechanism you choose (event bus or wiring the views together), you should now have access directly to the instance of the widget you want to highlight. To focus, just call setFocus(true) on it.