i researched many posts and articles around this, but could not get a good answer.
i am running into issues while implementing search using Navigation Architecture component.
i have a MainActivity, mainFragment and a searchFragment. mainFragment is set as destination in my navigationGraph. i have these doubts
1. Search should be made part of activity or mainFragment what is the right approach.
2. If search is made part of Activity then handling the up button for my search becomes an issue. the up button on search exits the MainActivity, does not land in mainFragment. I was thinking that NavController should have stack containing mainFragment and then searchFragment, once you press up button in searchFragment, it should popout and mainFragment should display. Looks like i am missing something.
Related
I need to implement the routing functionality in Xamarin.Forms application using the ReactiveUI framework.
The following transitions map needs to be implemented:

Above the black arrows show forward transitions (e.g. I go from the Menu to the Order page by clicking on the menu item button), while the red arrows are for Go Back functionality. Please note that Go back should work for both: (a) the "Go back" link in the top navigation bar (b) the hardware «Back» button on the Android devices.
How do I implement the transitions between sibling pages like these:
Menu - Order - Map - Back to the Menu
Menu - Order - Order details - Pin details page - Back to the Map - Back to the Menu
?
P.S. Here is the guide https://www.reactiveui.net/docs/handbook/routing/ I followed recently, so I used GoNext/GoBack commands to implement more simple transitions like Menu - Order - Order details - Back to the Order - Back to the Menu. It does not work well for the described case, as the Back buttons make transitions back to the previous page instead of their parent page in the navigation map.
The NavigateBack command implementation is quite simple in ReactiveUI's RoutingState, it just removes the last element from the RoutingState.NavigationStack, RoutingState.NavigationStack is an instance of ObservableCollection<IRoutableViewModel>.
So in your particular case, you could write your own NavigateBack command implementation that mutates the navigation stack as required by your application domain. You could use a switch block to figure out what page is currently shown in the screen, and then map that page into another page, either newly created or stored in a field or in a Locator.Current. Probably your command will require a more complex canExecute implementation as well.
ReactiveCommand<Unit, IRoutableViewModel> navigateBackDomainAware =
ReactiveCommand.CreateFromObservable(() => {
var currentViewModel = NavigationStack[NavigationStack.Count - 1];
if (currentViewModel is PinDetailsViewModel) {
var mapViewModel = GetMapViewModel();
NavigationStack.Add(mapViewModel); // The navigation.
return Observable.Return(mapViewModel);
} else {
// Handle other pages. You can also put some domain-specific code
// describing the navigation mappings in your application here.
}
});
I am new to android and working on an app like dictionary.I am using search view from actionbar compat for searching suggestion and it is working good.
The problem is I want the search view on left aligned(where title shows) on actionbar and opened when the activity loads which is ok with normal devices but on tab it looks right aligned.
I have tried all the combination of showAsAction="" and setIconified() and setIconifiedByDefault() but not getting the desired result.
I want to use the default search view not custom if it is possible. I have searched a lot for this.
Is there any way(or link) by which i can get the desired output.
menu.xml:
android:id="#+id/action_search"
android:icon="#drawable/ic_action_search"
android:title="#string/action_search"
app:actionViewClass="android.support.v7.widget.SearchView"
app:showAsAction="always">
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
SearchManager manager = (SearchManager)getSystemService(Context.SEARCH_SERVICE);
searchView =(SearchView)enuItemCompat.getActionView(menu.findItem(R.id.action_search));
searchView.setSearchableInfo(manager.getSearchableInfo(getComponentName()));
searchView.setOnQueryTextListener(mOnQueryTextListener);
searchView.setIconified(false);
Thanks in advance...
I think I need to bind data programmatically to solve my problem.
I use a TabHost which hosts 2 Tabs.
I need to load the MvxBindableListView in the second tab when TabHost appears and keep the first tab as default tab.
What I'm doing is starting the second tab activity without problem because I check the process using this code:
protected override void OnViewModelSet()
{
SetContentView(Resource.Layout.Page_ActivityView);
System.Diagnostics.Debug.WriteLine("activityView started");
MvxBindableListView mvxBindableListView = FindViewById<MvxBindableListView>(Resource.Id.mvxBindableListView);
mvxBindableListView.ChildViewAdded += new System.EventHandler<Android.Views.ViewGroup.ChildViewAddedEventArgs>(mvxBindableListView_ChildViewAdded);
}
"activityView started" is displayed in output debugger, but MvxBindableListView.ChildViewAdded event isn't raised, only when I click the second tab.
So I suppose that MvxBindableListView is not databound.
Thanks in advance to help me loading my second tab programmatically.
I think ChildViewAdded is an event that occurs when the ListView is rendered - at that time when it needs to 'draw list items', then it will ask its adapter for child Views for the screen. As you scroll down the list, it will then ask for more child views - but it will also reuse views - so for a simple list you should only ever (hopefully) get N+1 calls on ChildViewAdded for a list which shows N items at one time.
So it's perfectly possible for a list to be databound but never to call ChildViewAdded - that won't get called until the list is 'drawn'
Sadly the Xamarin docs aren't helpful here - http://docs.mono-android.net/monodoc.ashx?link=E%3AAndroid.Views.ViewGroup.ChildViewAdded
Note: if you do actually want to bind programatically, then you can do this to - using Bind() methods and extension methods. However, I haven't expanded on that here - as it doesn't sound like that's actually what you need!
I am using vaadin in a portlet environment where we have specific validation look & feel and behavior.
When input fields have invalid values,
their borders color becomes red.
All the error messages (as link) are shown above or below at common location.
Clicking on specific error results into cursor focus going to related field.
So how can i achieve this functionality and what i need to change & modify.
For your point #1, You need to create a theme. To do that, I suggest you to read the Book of Vaadin chapter 5 and 8.
Chapter 5 explain the ui component and css style associated with them.
Chapter 8 explain how to inherits a css theme.
For point #2, You have to add a layout to your page, and for each message youy will create a button and style it like a web link.
Button button = new Button("Your error message");
button.setStyle(BaseTheme.BUTTON_LINK);
errorLayout.addComponent(button);
For point #3, add listener to your button link, and when clicked, focus the component in error. So the previous code will now look like this
Button button = new Button("Your error message");
button.setStyle(BaseTheme.BUTTON_LINK);
button.addListener(new Button.ClickListener(){
public void buttonClick(ClickEvent event){
// Replace componentInError by the associated component of the link.
componentInError.focus();
}
}
errorLayout.addComponent(button);
Regards.
Éric
Right now, I'm working on my first WP7 app and have run into some questions, which I haven't been able to answer despite reading what I could find online. Please consider an app that has a main page, a parameters page and a results page. In the parameters page, the user can enter or update numbers in various textboxes. Hitting the back button takes the user back to the main page, where there is a button called "Calculate". Hitting that button should take the data, perform a calculation with it and take the user to the results page presenting a grid with the results.
In a file called Calculator.cs I have a class called Calculator inside a folder called Models. I also have my MainViewModel.cs, ParametersViewModel.cs, and ResultsViewModel.cs files inside the ViewModels folder and the corresponding MainPage.xaml, along with Parameters.xaml and Results.xaml inside a folder called Views. I'm assuming that all the data will be manipulated within the instance of the Calculator class and then a results set will be returned and directed to Results.xaml. I'm just at a loss as to where to instantiate the Calculator class, pass it data, then retrieve the results. I'm also somewhat puzzled how I will trigger the automatic navigation to the Results page when the calculation is done.
Any help with this would be greatly appreciated.
UPDATE: Passing a complex object to a page while navigating in a WP7 Silverlight application has some more info on the same subject. I can go into App.xaml.cs and add something like this:
public class Foobar
{
public string barfoo = "hah!";
}
public static Foobar myfoob = new Foobar();
Then access it from a ViewModel page, e.g. AboutViewModel.cs, like this:
public AboutViewModel()
{
string goo = App.myfoob.barfoo;
}
But at this point I'm still uncertain what unforseen effects that might have. I'm going to tackle serialization/tombstoning at this point to see what happens with either this approach or by using the same DataContext across pages. Otherwise, one of the posters in the link above mentioned serializing the params and passing them between pages. My concern there would be whether or not there is a character limit as with HTTP GET. Seems there is: URI Limits in Silverlight
There are of course lots of possible designs - and lots of them are correct in different ways!
Here's one I might use:
The Calculate button press should trigger the Navigate to the Results page
On navigate to, the Results page should show some animation (maybe just a progress bar)
On navigate to, the Results page should create a new ResultsViewModel, passing in the MainViewModel as parameters
the constructor (or some init method) of the ResultsViewModel should spark up a thread to do the calculation
when this calculation is complete, then the relevant properties of the ResultsViewModel will get set
at which point the databinding on the Results page will clear the animation and show the results
Other solutions are definitely available - will be interested to read what other people suggest and prefer.
As an aside, one thing to watch out for on your Results page is tombstoning - could be an interesting challenge!