C# UITextField.AddTarget方法代码示例

        public override void ViewDidLoad()
        {
            base.ViewDidLoad ();
            //scrollView = stackView.Superview as UIScrollView;
            //scrollView.KeyboardDismissMode = UIScrollViewKeyboardDismissMode.OnDrag;
            //scrollView.ScrollEnabled = true;
            // Set up Navigation Bar
            var saveButton = new UIBarButtonItem (UIBarButtonSystemItem.Save, save);
            var cancelButton = new UIBarButtonItem (UIBarButtonSystemItem.Cancel, cancel);
            NavigationItem.Title = "New Medication:";
            NavigationItem.RightBarButtonItem = saveButton;
            NavigationItem.HidesBackButton = true;
            NavigationItem.LeftBarButtonItem = cancelButton;

            //NSNotificationCenter.DefaultCenter.AddObserver (this, new ObjCRuntime.Selector("keyboardDidAppear:"), UIKeyboard.DidShowNotification, null);
            //NSNotificationCenter.DefaultCenter.AddObserver (this, new ObjCRuntime.Selector ("keyboardWillDissapear:"), UIKeyboard.WillHideNotification, null);

            // Set up the date formatter
            dateFormat = new NSDateFormatter();
            dateFormat.DateStyle = NSDateFormatterStyle.None;
            dateFormat.TimeStyle = NSDateFormatterStyle.Short;

            // Set up new pet form
            nameField = new UITextField();
            nameField.Text = "Medication Name";
            nameField.BorderStyle = UITextBorderStyle.RoundedRect;
            nameField.ReturnKeyType = UIReturnKeyType.Done;

            medTypeLabel = new UILabel ();
            medTypeLabel.Text = "Type of Medication";
            medTypeButton = new UIButton (UIButtonType.RoundedRect);
            medTypeButton.AddTarget (editMedType, UIControlEvent.TouchUpInside);
            medTypeButton.SetTitle ("Pill", UIControlState.Normal);
            medTypeButton.TitleLabel.Font = medTypeButton.TitleLabel.Font.WithSize (medTypeLabel.Font.PointSize);
            medTypePicker = new UIPickerView ();
            medTypePicker.Delegate = new MedTypePickerDelegate (this);
            medTypePicker.DataSource = new MedTypePickerDataSource ();

            freqLabel = new UILabel ();
            freqLabel.Text = "Frequency";
            freqTextField = new UITextField ();
            freqTextField.Text = "1";
            freqTextField.KeyboardType = UIKeyboardType.NumberPad;
            freqTextField.BorderStyle = UITextBorderStyle.RoundedRect;
            freqTextField.Enabled = false;
            freqTextField.AddTarget (freqTextFieldChanged, UIControlEvent.EditingDidEnd | UIControlEvent.EditingDidEndOnExit);
            freqStepper = new UIStepper ();
            freqStepper.Value = 1;
            freqStepper.MinimumValue = 1;
            freqStepper.Enabled = false;
            freqStepper.AddTarget (freqStepperIncremented, UIControlEvent.ValueChanged);
            UIStackView freqStackView = new UIStackView (new UIView[] { freqTextField, freqStepper });
            freqStackView.Spacing = 8;
            freqStackView.Axis = UILayoutConstraintAxis.Horizontal;
            freqButton = new UIButton (UIButtonType.RoundedRect);
            freqButton.SetTitle ("Daily", UIControlState.Normal);
            freqButton.TitleLabel.Font = freqButton.TitleLabel.Font.WithSize (medTypeLabel.Font.PointSize);
            freqButton.AddTarget (editFrequency, UIControlEvent.TouchUpInside);
            freqPicker = new UIPickerView ();
            freqPicker.Delegate = new MedFreqPickerDelegate (this);
            freqPicker.DataSource = new MedFreqPickerDataSource ();

            timePicker = new UIDatePicker ();
            gregorian = new NSCalendar (NSCalendarType.Gregorian);
            timePicker.Date = gregorian.DateBySettingsHour (9, 0, 0, NSDate.Now, NSCalendarOptions.MatchNextTime);
            timePicker.Mode = UIDatePickerMode.Time;
            timePicker.AddTarget (timePickerChanged, UIControlEvent.AllEvents);

            UILabel timeLabel = new UILabel ();
            timeLabel.Text = "Time";
            timeButtons = new UIButton[1];
            timeDates = new NSDate[1];
            timeDates [0] = gregorian.DateBySettingsHour (9, 0, 0, NSDate.Now, NSCalendarOptions.MatchNextTime);
            timeButtons [0] = new UIButton (UIButtonType.RoundedRect);
            timeButtons [0].SetTitle ("9:00 AM", UIControlState.Normal);
            timeButtons [0].AddTarget (openTimePicker, UIControlEvent.TouchUpInside);
            timeStack = new UIStackView ();
            timeStack.Alignment = UIStackViewAlignment.Leading;
            timeStack.Distribution = UIStackViewDistribution.FillProportionally;
            timeStack.Spacing = 5;
            timeStack.Axis = UILayoutConstraintAxis.Vertical;
            timeStack.AddArrangedSubview (timeLabel);
            foreach (var button in timeButtons) {
                timeStack.AddArrangedSubview (button);
            }
            timeStack.AddArrangedSubview (timePicker);
            timePicker.Hidden = true;

            dayLabel = new UILabel ();
            dayLabel.Text = "Day";
            dayLabel.Hidden = true;
            dayButton = new UIButton (UIButtonType.RoundedRect);
            var day = gregorian.GetComponentFromDate (NSCalendarUnit.Weekday, NSDate.Now);
            dayButton.SetTitle (gregorian.WeekdaySymbols[day], UIControlState.Normal);
            dayButton.AddTarget (openDayPicker, UIControlEvent.TouchUpInside);
            dayButton.Hidden = true;
            dayPicker = new UIDatePicker ();
            dayPicker.Mode = UIDatePickerMode.Date;
            dayPicker.MinimumDate = NSDate.Now;
            dayPicker.MaximumDate = NSDate.Now.AddSeconds (604800);
//.........这里部分代码省略.........

		protected virtual void PrepareEntry(UITableView tableview){
			SizeF size = _computeEntryPosition(tableview);
			
			_entry = new UITextField (new RectangleF (size.Width+10, (ContentView.Bounds.Height-size.Height)/2-1, 320-size.Width, size.Height));
			
			TextLabel.BackgroundColor = UIColor.Clear;
			_entry.AutoresizingMask = UIViewAutoresizing.FlexibleWidth |
				UIViewAutoresizing.FlexibleLeftMargin;
			
			_entry.ValueChanged += delegate {
				if (_element != null)
					_element.Value = _entry.Text;
			};
			_entry.Ended += delegate {
				if (_element != null)
					_element.Value = _entry.Text;
			};
			
			_entry.AddTarget((object o, EventArgs r)=>{
				if (_element != null)
					_element.Value = _entry.Text;
				}, UIControlEvent.EditingChanged);
				
			_entry.ShouldReturn += delegate {
				Element elementToFocusOn = null;
				
				foreach (var c in ((Section)_element.Parent).Elements){
					if (c == _element)
						elementToFocusOn = c;
					else if (elementToFocusOn != null && c is EntryElement)
						elementToFocusOn = c as EntryElement;
				}
				if (elementToFocusOn != _element && elementToFocusOn!=null) {
                    var index = elementToFocusOn.GetIndexPath();
					var cell = tableview.CellAt(index);
                    tableview.ScrollToRow(index, UITableViewScrollPosition.Bottom, true);
					cell.BecomeFirstResponder();
				}
				else 
					_entry.ResignFirstResponder();

                if (_entry.ReturnKeyType == UIReturnKeyType.Go) {
                    _element.FireGo(this, EventArgs.Empty);
                }

				return true;
			};
			_entry.Started += delegate {
				EntryElement self = null;
				var returnType = _element.ReturnKeyType;

                if (returnType != UIReturnKeyType.Default) {
                    foreach (var e in (_element.Parent as Section).Elements){
                        if (e == _element)
                            self = _element;
                        else if (self != null && e is EntryElement)
                            returnType = UIReturnKeyType.Next;
                    }
                }
                _entry.ReturnKeyType = returnType;
			};
				
			ContentView.AddSubview (_entry);
		}