Is there any way to prevent the change of a tab in TabControl in Silverlight 4?
A simple case is when I've got a form with some data, and I want to ask the user if he/she wants to save this data before actually changing the tab.
I've seen code examples on how to do this in WPF, but not in Silverlight.
What can I do to stop the tab from changing?
Bind SelectedIndex to a property on your data context.
<sdk:TabControl SelectedIndex="{Binding SelectedIndex, Mode=TwoWay}">
<sdk:TabItem Header="TabItem">
<Grid Background="#FFE5E5E5"/>
</sdk:TabItem>
<sdk:TabItem Header="TabItem">
<Grid Background="#FFE5E5E5"/>
</sdk:TabItem>
</sdk:TabControl>
In the SET accessor, write your code to check whether the user really wants to do what they're trying to do.
public class Context : INotifyPropertyChanged
{
int _SelectedIndex = 0;
public int SelectedIndex
{
get
{
return _SelectedIndex;
}
set
{
MessageBoxResult result = MessageBox.Show("Do you want to save?", "Really?", MessageBoxButton.OKCancel);
if (result == MessageBoxResult.OK)
{
_SelectedIndex = value;
}
RaisePropertyChanged("SelectedIndex");
}
}
#region INotifyPropertyChanged Members
public event PropertyChangedEventHandler PropertyChanged;
private void RaisePropertyChanged(string propertyName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
}
#endregion
}
Net effect is, if the user chooses 'cancel' on the dialogue the private variable is never changed - the PropertyChanged event fires, rebinding the selected index to the existing value.
Hope this is what you were trying to accomplish.
UPDATE (11/10/2012) - Alternate method (possibly for SL5?). Write code behind to tie into SelectionChanged event of your TabControl, reset the tab control's selected item property based on your test.
private void TabControl_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
{
if (e.RemovedItems.Count > 0)
{
MessageBoxResult result = MessageBox.Show("Do you want to save?", "Really?", MessageBoxButton.OKCancel);
if (result != MessageBoxResult.OK)
{
((TabControl)sender).SelectionChanged -= new SelectionChangedEventHandler(TabControl_SelectionChanged);
((TabControl)sender).SelectedItem = e.RemovedItems[0];
((TabControl)sender).SelectionChanged += new SelectionChangedEventHandler(TabControl_SelectionChanged);
}
}
}
Related
I need to run some address validation on Customer Location addresses using a 3rd party API to determine if the address is residential or commercial. This validation should run whenever an address field is changed. In other words, the validation should be run in the Address_RowUpdated event handler.
Because the function is calling a 3rd party API, I believe that it should be done in a separate thread, using PXLongOperation so that it does not hold up address saving and fails gracefully if the API is unavailable or returns an error.
However, I am not sure if the architecture of running a long operation within an event handler is supported or if a different approach would be better.
Here is my code.
public class CustomerLocationMaint_Extension : PXGraphExtension<CustomerLocationMaint>
{
protected virtual void Address_RowUpdated(PXCache sender, PXRowUpdatedEventArgs e)
{
PX.Objects.CR.Address row = (PX.Objects.CR.Address)e.Row;
if (row != null)
{
Location location = this.Base.Location.Current;
PXCache locationCache = Base.LocationCurrent.Cache;
PXLongOperation.StartOperation(Base, delegate
{
RunCheckResidential(location, locationCache);
});
this.Base.LocationCurrent.Cache.IsDirty = true;
}
}
protected void RunCheckResidential(Location location, PXCache locationCache)
{
string messages = "";
PX.Objects.CR.Address defAddress = PXSelect<PX.Objects.CR.Address,
Where<PX.Objects.CR.Address.addressID, Equal<Required<Location.defAddressID>>>>.Select(Base, location.DefAddressID);
FValidator validator = new FValidator();
AddressValidationReply reply = validator.Validate(defAddress);
AddressValidationResult result = reply.AddressResults[0];
bool isResidential = location.CResedential ?? false;
if (result.Classification == FClassificationType.RESIDENTIAL)
{
isResidential = true;
} else if (result.Classification == FClassificationType.BUSINESS)
{
isResidential = false;
} else
{
messages += "Residential classification is: " + result.Classification + "\r\n";
}
location.CResedential = isResidential;
locationCache.Update(location);
Base.LocationCurrent.Update(location);
Base.Actions.PressSave();
// Display relevant messages
if (reply.HighestSeverity == NotificationSeverityType.SUCCESS)
String addressCorrection = validator.AddressCompare(result.EffectiveAddress, defAddress);
if (!string.IsNullOrEmpty(addressCorrection))
messages += addressCorrection;
}
PXSetPropertyException message = new PXSetPropertyException(messages, PXErrorLevel.Warning);
PXLongOperation.SetCustomInfo(new LocationMessageDisplay(message));
//throw new PXOperationCompletedException(messages); // Shows message if you hover over the success checkmark, but you have to hover to see it so not ideal
}
public class LocationMessageDisplay : IPXCustomInfo
{
public void Complete(PXLongRunStatus status, PXGraph graph)
{
if (status == PXLongRunStatus.Completed && graph is CustomerLocationMaint)
{
((CustomerLocationMaint)graph).RowSelected.AddHandler<Location>((sender, e) =>
{
Location location = e.Row as Location;
if (location != null)
{
sender.RaiseExceptionHandling<Location.cResedential>(location, location.CResedential, _message);
}
});
}
}
private PXSetPropertyException _message;
public LocationMessageDisplay(PXSetPropertyException message)
{
_message = message;
}
}
}
UPDATE - New Approach
As suggested, this code now calls the LongOperation within the Persist method.
protected virtual void Address_RowUpdated(PXCache sender, PXRowUpdatedEventArgs e)
{
PX.Objects.CR.Address row = (PX.Objects.CR.Address)e.Row;
if (row != null)
{
Location location = Base.Location.Current;
LocationExt locationExt = PXCache<Location>.GetExtension<LocationExt>(location);
locationExt.UsrResidentialValidated = false;
Base.LocationCurrent.Cache.IsDirty = true;
}
}
public delegate void PersistDelegate();
[PXOverride]
public virtual void Persist(PersistDelegate baseMethod)
{
baseMethod();
var location = Base.Location.Current;
PXCache locationCache = Base.LocationCurrent.Cache;
LocationExt locationExt = PXCache<Location>.GetExtension<LocationExt>(location);
if (locationExt.UsrResidentialValidated == false)
{
PXLongOperation.StartOperation(Base, delegate
{
CheckResidential(location);
});
}
}
public void CheckResidential(Location location)
{
CustomerLocationMaint graph = PXGraph.CreateInstance<CustomerLocationMaint>();
graph.Clear();
graph.Location.Current = location;
LocationExt locationExt = location.GetExtension<LocationExt>();
locationExt.UsrResidentialValidated = true;
try
{
// Residential code using API (this will change the value of the location.CResedential field)
} catch (Exception e)
{
throw new PXOperationCompletedWithErrorException(e.Message);
}
graph.Location.Update(location);
graph.Persist();
}
PXLongOperation is meant to be used in the context of a PXAction callback. This is typically initiated by a menu item or button control, including built-in actions like Save.
It is an anti-pattern to use it anytime a value changes in the web page. It should be used only when a value is persisted (by Save action) or by another PXAction event handler. You should handle long running validation when user clicks on a button or menu item not when he changes the value.
For example, the built in Validate Address feature is run only when the user clicks on the Validate Address button and if validated requests are required it is also run in a Persist event called in the context of the Save action to cancel saving if validation fails.
This is done to ensure user expectation that a simple change in a form/grid value field doesn't incur a long validation wait time that would lead the user to believe the web page is unresponsive. When the user clicks on Save or a specific Action button it is deemed more reasonable to expect a longer wait time.
That being said, it is not recommended but possible to wrap your PXLongOperation call in a dummy Action and asynchronously click on the invisible Action button to get the long operation running in the proper context from any event handler (except Initialize):
using PX.Data;
using System.Collections;
namespace PX.Objects.SO
{
public class SOOrderEntry_Extension : PXGraphExtension<SOOrderEntry>
{
public PXAction<SOOrder> TestLongOperation;
[PXUIField(DisplayName = "Test Long Operation", Visible = false, Visibility = PXUIVisibility.Invisible)]
[PXButton]
public virtual IEnumerable testLongOperation(PXAdapter adapter)
{
PXLongOperation.StartOperation(Base, delegate ()
{
System.Threading.Thread.Sleep(2000);
Base.Document.Ask("Operation Done", MessageButtons.OK);
});
return adapter.Get();
}
public void SOOrder_OrderDesc_FieldUpdated(PXCache sender, PXFieldUpdatedEventArgs e)
{
if (!PXLongOperation.Exists(Base.UID))
{
// Calling Action Button asynchronously so it can run in the context of a PXAction callback
Base.Actions["TestLongOperation"].PressButton();
}
}
}
}
So I have a user control with six textboxes and a few buttons. One of those buttons is 'clear'. When I click the clear button, in the btnClear_Click handler, I want to find all the textboxes in my user control (and ONLY in my user control). And then set them to an empty string. That's it. That's all.
This is turning out to be a herculean, insurmountably difficult thing to do. Finding an answer is like trying to map the human genome. I just want to ITERATE THROUGH THE CONTROLS. Nothing more.
I'm not interested in hearing about the merits of what I'm trying to do. Just the mechanics of how to do it. Something like this:
public partial class myUserControl: UserControl
{
private void btnClear_Click(object sender, RoutedEventArgs e)
{
var allMyControls = SomeMiraculousOperationToGetAllControlsThatOnlyExistInMyUserControl();
foreach (var control in allMyControls)
{
if (control is TextBox)
((TextBox)control).Text = string.Empty;
}
}
}
You can use the VisualTreeHelper to enumerate the child controls of your user control.
You can find an extension method base on this class here
public static T GetChildOfType<T>(this DependencyObject depObj)
where T : DependencyObject
{
if (depObj == null) return null;
for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
{
var child = VisualTreeHelper.GetChild(depObj, i);
var result = (child as T) ?? GetChildOfType<T>(child);
if (result != null) return result;
}
return null;
}
I am using MVVMCross 3.2.2 as part of an iOS/Android app. One of my screens has multiple views that are displayed depending upon the selection in a Tab bar like row of buttons. Different data is displayed in each of these these views individual UITableView. The data binding works perfectly.
I also have a menu, that has a "profile" selection. Changing the profile fires an MvxMessage that my HomeView receives and then uses the message to set the ViewModel up to filter the data to be displayed. This all seems to work perfectly and the data is displayed correctly.
If I do something in the HomeView that displays another view using ShowViewModel(). When I return back to the home view the binding no longer works properly when a profile changes is made. The message gets handled, the data gets filtered, but a call to ReloadDataTable on the UITableView does not change the data.
ViewModel
#region Groupings
public IList<Group> Groups{
get { return _groupService.GetAll(); }
}
public void SetupSubGroups(Group group)
{
if (group == null)
{
_groups = new ObservableCollection<Group> ();
if (_profileService.SelectedProfile != null)
{
var grp = _groupService.GetByGroupName (_profileService.SelectedProfile.Name);
if (grp == null)
grp = new Group { Name = _profileService.SelectedProfile.Name };
_groups.Add (grp);
}
}
else
{
var litsOfGroups = _groupService.GetSubGroups (group);
foreach (var grp in litsOfGroups)
_groups.Add (grp);
}
RaisePropertyChanged(() => AvailableGroups);
}
private ObservableCollection <Group> _groups;
public ObservableCollection<Group> AvailableGroups {
get { return _groups; }
}
#endregion
ViewController
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
var groupSource = new GroupTableViewDataSource (TableViewGroups);
TableViewGroups.Source = groupSource;
_localViewModel.SetupSubGroups (null);
_bindingSet = this.CreateBindingSet<HomeViewController, HomeViewModel> ();
_bindingSet.Bind (groupSource).To (vm => vm.AvailableGroups);
_bindingSet.Apply ();
TableViewReportTags.ReloadData ();
NavigationController.NavigationBarHidden = false;
}
private void OnProfileChanged(ProfileChangedMessage message)
{
_localViewModel.SetupSubGroups (null);
TableViewGroups.ReloadData ();
}
private HomeViewModel _localViewModel { get { return ViewModel as HomeViewModel; } }
Any ideas what I can look at, or change would be really useful. I have spend many hours on this, and have made no progress.
I am trying to do per-keystroke validation in a JavaFX TextFieldTableCell but I do not know how to capture the text-changed events from the embedded TextField control.
If the object in question were simply a TextField, then textField.textProperty().addListener(myChangeListener) would do the trick. TextFieldTableCell also exposes textProperty(), but this property behaves quite differently on TextFieldTableCell. It does not generate change events on a per-keystroke basis. Rather, I see lots of events when the TableView is first displayed, and I see one event each time I begin editing in a cell.
First of all, about textProperty().
Look here to see :
http://docs.oracle.com/javafx/2/api/index.html
TextProperty() is a property of labeled parent class, you will learn nothing from it, because it is not used. It is tricky thing : cell - inheritant of labeled control. TextField, which you see, when start editing, it is a graphic node of cell (graphicProperty()) (as far as I remember documentation).
And, this graphic node is assigned by a text field, only when editing starts.
AFAIK, there is no direct access to editable node.
The way to solve the issue - implement editable cell by your self.
Let me talk to developer, to learn more...
Supposing, you have DataItem class, which contains String, and supposing that TableView has encapsulated data type DataItem, and the only column has the same encapsulated data type, you may use this implementation as basis :
public class TextFieldTableCell extends TableCell<DataItem, DataItem> {
private TextField textField;
public TextFieldTableCell() {
}
#Override
public void startEdit() {
super.startEdit();
if (isEmpty()) {
return;
}
if (textField == null) {
createTextBox();
} else {
textField.setText(new CellCustomStringConverter().toString(getItem()));
}
setGraphic(textField);
setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
textField.requestFocus();
textField.selectAll();
}
#Override
public void cancelEdit() {
super.cancelEdit();
setContentDisplay(ContentDisplay.TEXT_ONLY);
}
#Override
public void updateItem(DataItem item, boolean empty) {
super.updateItem(item, empty);
if (!isEmpty()) {
if (textField != null) {
textField.setText(new CellCustomStringConverter().toString(item));
}
setText(item.toString());
}
}
private void createTextBox() {
textField = new TextField(new CellCustomStringConverter().toString(getItem()));
textField.setId(TABLE_EDIT_ID);
textField.setOnKeyReleased(new EventHandler<KeyEvent>() {
#Override
public void handle(KeyEvent t) {
if (t.getCode() == KeyCode.ENTER) {
commitEdit(new DataItem(textField.getText()));
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
}
});
}
}
I have a usercontrol that I want to have the grid inside so I don't have to duplicate that grid on every page. Except when I sort, page, or anything that does a post back the usercontrol reloads and loses its datasource. My plan is to retrieve the search criteria from the parent page(since it already has it from the criteria controls). That way when the NeedDataSource is called it still has the criteria to pass back the right results.
How do I get where you see SuperSearch to be whichever page might be the parent like StateToState.
public SearchCriteria SearchCriteria
{
get
{
Page parent = this.Page;
if (parent != null)
{
var superSearch = parent as SuperSearch;
if (superSearch != null) return superSearch.SearchCriteria;
}
return new SearchCriteria();
}
}
Create an event handler 'event EventHandler NeedSearchCriteria' on your usercontrol that gets fired on your parent page
On your aspx page:
<UC:Grid runat="server" ID="ucGrid" OnNeedSearchCriteria="ucGrid_OnNeedSearchCriteria" />
In the code behind:
public void ucGrid_OnNeedSearchCriteria(object sender, EventArgs e)
{
ucGrid.Criteria = Criteria;
}
And on the usercontrol code behind:
public event EventHandler NeedSearchCriteria;
private SearchCriteria _criteria;
public SearchCriteria Criteria
{
get
{
if (_criteria == null && NeedSearchCriteria != null)
{
NeedSearchCriteria(this, new EventArgs());
}
return _criteria ?? new SearchCriteria();
}
set
{
_criteria = value;
}
}