Passing Managed Object Data Through didSelectRow UIPickerView - core-data

I'm a bit lost on how to pass my fetched managed object data through a didSelectRow UIPickerView action.
On the previous view, I passed the CalcInfo object like this:
CalcInfo *calc = (CalcInfo *)[_calcInfos objectAtIndex:indexPath.row];
self.myPageOneViewController.calcInfos = calc;
I was successfully able to use calcInfos.attribute for all my IBAction:(id)sender buttons, but the pickerView isn't able to fetch / use the data. The updateLabel action always has calcInfos.attribute as NULL. Here's a bit of my code
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
[self updateLabel];
}
- (void)updateLabel {
double stdrate = [calcInfos.infusionstd doubleValue];
double lowrate = [calcInfos.infusionlow doubleValue];
if (calcInfos.infusionlow == NULL) {
NSLog(#"It's null");
}
}
Your help is much appreciated!

The picker view is a subview with its own hardwired controller. It returns the row and column/component picked in its delegate message `didSelectRow:inComponent'.
You need to pass that info along to your updateLabel method so that you can relate the pickerview selection to your managed objects. Right now, the method does nothing at all.

Related

UICollectionview SelectItem programmatically not changing background

I have a UICollectionView with images. The user can select (multiselect) the images. When the user taps a single image, everything works fine. The SelectedBackgroundView is visible and on tap again, the normal image is visible.
But my problem is, I have a option for the user "Select all". In that i want to select all items programmatically. With following code:
for (int i = 0; i < CollectionView.NumberOfItemsInSection(0); i++)
{
var ip = NSIndexPath.FromItemSection(i, 0);
CollectionView.SelectItem(ip, false, UICollectionViewScrollPosition.None);
}
The following method returns the correct number for the selected items:
var number = CollectionView.GetIndexPathsForSelectedItems().Length;
But the UI is not changing to the SelectedBackgroundView.
Can anyone help me? Thanks.
Calling SelectItem does not cause the display to be updated; it just changes the Selected property of the UICollectionViewCell therefore updating the selected index set in the collection view.
What I do is override the Selected property of my UICollectionViewCell implementation and adjust the UI at that point:
public class MyCell : UICollectionViewCell
{
// ...
public override bool Selected
{
get { return base.Selected; }
set
{
base.Selected = value;
// change the state of the selected background
imageBackground.Image = LoadAnImage(value ? "BackgroundOn" : "BackgroundOff");
}
}
}
This way ensures that the UI is updated at all possible points when the selected state of the cell changes, either by user interaction or programmatically calling SelectItem or DeselectItem on the collection view.
I do not personally use the SelectedBackgroundView property on a cell (I do my own layering, most of the time), but you may have to manually bring that view to the front yourself in a similar Selected property override.

pass core data record from uiview

I've a little issue in my app. my app is based on core data using magical record.
In my first view ( a tableview) I have all the data, when one of the cell is tapped, it open the second view (detail UIview).
But i don't have enough space to show all the detail so i create a second detail view from the first one ( I don't want a scroll view).
the segue between the tableView and the firstDetailView work perfectly
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"showDetail"]) {
NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
DetailViewController*dvc = segue.destinationViewController;
dvc.indice = indexPath.row;
}
}
But when I go to the second detail UIview I always get the detail of the first record in the tableview. I think the problem is in the prepareForSegue method, but I can't figure out how to solve it,
Somebody could help me??
I created another property in the second detail view and set it equal to the property "indice" of the first detail view
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"showMaking"]) {
DettaglioPreferito2*dvc = segue.destinationViewController;
dvc.indiceDue = self.indice;
}
}

Customs binding cross views in mvvmcross

I need a custom binding and I know when and where but I don't know how I can do it. This is the relation of the view in my custom binding. Think about the *Views like controls.
I have the connections from ViewModel->ContainerView->FirstView but I can't connect it with the TableView. To connect the ContainerView to FirstView I did a custom binding (in one direction for now). And in the setvalue method I call the firstview's method SetBinding (where I want to do the binding)
I tried a few option but nothing happens, the last one looks like this:
public GolferList CurrentGolferList { get; set; }
public void SetBinding(GolferList golferList){
this.CurrentGolferList = golferList;
TableSource = new TableSourcePlayers(TableViewPlayers);
var bindingDescription = new[]{
new MvxBindingDescription {TargetName = "ItemsSource",SourcePropertyPath = "CurrentGolferList"} ,
};
Binder.Bind(this,TableSource, bindingDescription);
TableViewPlayers.Source = TableSource;
TableViewPlayers.ReloadData();
}
I would be grateful if you could tell me another way to handle it.
Update:
I followed Stuart's link and now it works fine, thanks a lot Stuart!
Actually, in my scheme the TableView is a MvxSimpleBindableTableViewSource and I want to bind the data there. So in order to make it work, I used the code below (SetBinding needs some external refactor):
private List<IMvxUpdateableBinding> bindings;
private string BindingText = "{'ItemsSource':{'Path':'CurrentGolfers'}}";
public object DataContext {
get { return dataContext; }
set { dataContext = value;
if (bindings == null)
bindings = this.GetService<IMvxBinder>().Bind(dataContext, TableSource, BindingText).ToList();
else
bindings.ForEach(b => b.DataContext = dataContext);
}
}
public void SetBinding(GolferList golferList){
this.DataContext = PlayViewModel;
tableView.Source = TableSource;
tableView.ReloadData();
}
Note that BindingText points to the table, not to the view itself.
Update 2
Now in V3 it's a bit different. First, the view must implement IMvxBindable and this members:
public object DataContext
{
get { return BindingContext.DataContext; }
set { BindingContext.DataContext = value; }
}
public IMvxBindingContext BindingContext { get; set; }
(Don't forget dispose calling BindingContext.ClearAllBindings() and also call to CreateBindingContext() in the viewload )
And then you'll be able to bind in your class. In my case:
var set = this.CreateBindingSet<FirstPlayViewController, PlayViewModel>();
set.Bind(source).To(vm => vm.CurrentGolfers).Apply(); //I love the new fluent api :)
I think what you want to do is actual a data-bound View, rather than a custom binding.
This is covered in this question - Custom bindable control in a MvvmCross Touch project
Basically what you need to do is to add a collection of 'Bindings' and the 'DataContext' property to your FirstView.
If you do that then you should be able to databind (to DataContext) within FirstView just like you do within any normal MvvmCross view.
Note - this will be much easier to do in v3 as we've added a 'BindingContext' object to assist with exactly this type of operation

MKAnnotationView RightCallOut button crashes my app when I click on it

I'm calling a service and returning a bunch of latitudes and longitudes which I'm then placing on a map using MapKit.
using MKAnnotationView I'm adding a RightCallOutButton to each annotation.
So I had to create a new MapDelegate. Code below.
If I click on the button I create the app crashes and I get an error from MonoTouch saying the selector is accings omething that has already been GC'd (garbage collected).
So my question would be, where should I set the RightCalloutAccessoryView and where should I create the button, if not in this code below?
public class MapDelegage : MKMapViewDelegate {
protected string _annotationIdentifier = "BasicAnnotation";
public override MKAnnotationView GetViewForAnnotation (MKMapView mapView, NSObject annotation) {
MKAnnotationView annotationView = mapView.DequeueReusableAnnotation(this._annotationIdentifier);
if(annotationView == null) {
annotationView = new MKPinAnnotationView(annotation, this._annotationIdentifier);
} else {
annotationView.Annotation = annotation;
}
annotationView.CanShowCallout = true;
(annotationView as MKPinAnnotationView).AnimatesDrop = true;
(annotationView as MKPinAnnotationView).PinColor = MKPinAnnotationColor.Green;
annotationView.Selected = true;
var button = UIButton.FromType(UIButtonType.DetailDisclosure);
button.TouchUpInside += (sender, e) => {
new UIAlertView("Testing", "Testing Message", null, "Close", null).Show ();
} ;
annotationView.RightCalloutAccessoryView = button;
return annotationView;
}
}
annotationView = new MKPinAnnotationView(annotation, this._annotationIdentifier);
...
var button = UIButton.FromType(UIButtonType.DetailDisclosure);
You should avoid declaring local variables to hold references you expect to outlive the method itself. Once there's no reference to annotationView or button the Garbage Collector (GC) is free to collect them (the managed part) even if it's native counterparts still exists. However when a callback to them is called you'll get a crash.
The easiest solution is to keep a list of them and (at the class level, i.e. a List<MKPinAnnotationView> field) clear the list when you destroy the view. The UIButton should not be necessary since there's a reference between the view and it.
NOTE: work is being done to hide this complexity from developers in future versions of MonoTouch. Sadly you cannot ignore such issues at the moment.

Monotouch-Dialog ReloadData does not reloads data?

I want to use monotouch dialog as not editable data display for some numeric values. But calling DialogViewController.ReloadData does not updates data from binded object.
class AccountFormModel
{
[Section("Account data", "")]
[Caption("Balance")]
public string balance;
}
...
private void InitComponents()
{
accountFormModel = new AccountFormModel();
accountFormModel.balance = "TestTestTest";
bc = new BindingContext(this, accountFormModel, "AccountData");
dialogViewController = new DialogViewController(bc.Root);
dialogViewController.Autorotate = true;
}
private void RefreshData()
{
string b = SomeDatasource.Account.Balance.ToString("N4");
accountFormModel.balance = "$" + b;
dialogViewController.ReloadData();
}
Debugging shows that accountFormModel.balance in refreshData method is set to right value, but nothing changes on form in simulator (stays TestTestTest). What i'm doing wrong?
DialogViewController when using reflection does the binding once initially, and only when you FetchData() is the data transferred back to your class.
What happens is that the BindingContext will basically create the model from your data (balance in this case) effectively making a copy of your data at this point. When you call ReloadData() this is reloading the data from the copy, and that is why you do not see a change. Although this could be changed to have some method on the BindingContex to repopulate the data, this is not currently the case.
The Reflection API for MonoTouch.Dialog is very limited, I strongly advise you that for anything non-trivial, you use the Elements API. Most of the samples in MonoTouch.Dialog use that API, as it gives you full control of the dialog.

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