I tried a very simple implementation, like this:
#implementation ScrollingTextField
- (void)scrollWheel:(NSEvent *)event {
self.doubleValue -= event.scrollingDeltaY;
}
#end
I bound the value of the scrolling text field to some other object. Scrolling now updates the visible text on the text field just fine. However, the bound value does not change.
Why does the bound value not change?
Or: How can I make the bound value recognize the change?
The bound value doesn't change by Apple's design. To propagate the value to the model yourself after a change, adapt this code:
NSDictionary *bindingInfo = [self infoForBinding:NSValueBinding];
[[bindingInfo valueForKey:NSObservedObjectKey] setValue:self.doubleValue
forKeyPath:[bindingInfo valueForKey:NSObservedKeyPathKey]];
(Thanks #DrummerB for that Apple link!)
Related
I have an NSPopupButton whose content is bound to an NSArray, let’s say the array is
#[
#"Option 1",
#"Option 2"
];
Its selected object is bound to User Defaults Controller, and is written to a preference file by the user defaults system.
In my code I check whether the preference is set to #"Option 1" or not, and perform actions accordingly.
This all worked well (though I did feel a little uneasy checking for what is essentially a UI value, but whatever...) until I needed to localize.
Because the value is the label, I’m having an issue.
If my user is in France, his preferences file will say #"L’option 1", which is not equal to #"Option 1". I need to abstract the presentation from the meaning and it's proving pretty difficult.
I split up the binding into two arrays, let's call them values and labels.
Let’s say they look like this:
values = #[
#"option_1",
#"option_2"
];
labels = #[
NSLocalizedString(#"Option 1", nil),
NSLocalizedString(#"Option 2", nil)
];
I’ve bound the NSPopUpButton’s Content binding to values and its Content Values binding to labels. However, the popup list is showing option_1 and option_2, it does not seem to want to use the labels array to label the items in the popup button.
How do I get the NSPopUpButton to use values internally and store that in the preferences file, but display labels to the user?
It doesn’t have to be architected this way, if you can think of a better solution. The point is I want to store and check one value, and have that value associated with a label that gets localized appropriately.
Cocoa bindings work very well with value transformers, because you can apply them directly in the bindings window, for example
#implementation LocalizeTransformer
+ (Class)transformedValueClass
{
return [NSArray class];
}
+ (BOOL)allowsReverseTransformation
{
return NO;
}
- (id)transformedValue:(id)value {
if (![value isKindOfClass:[NSArray class]]) return nil;
NSMutableArray *output = [NSMutableArray arrayWithCapacity:[value count]];
for (NSString *string in value) {
[output addObject:NSLocalizedString(string, nil)];
}
return [output copy];
}
#end
you have to register the transformer in awakeFromNib or better in +initialize
NSValueTransformer *localizeTransformer = [[LocalizeTransformer alloc] init];
[NSValueTransformer setValueTransformer:localizeTransformer
forName:#"LocalizeTransformer"];
then it appears in the popup menu of value transformers
Bind Selected Tag to your User Defaults Controller instead of Selected Object.
If the NSPopupButton choices are fixed add the NSMenuItems in Interface Builder and set their Tags. Otherwise bind an array of NSMenuItem, again with proper Tags.
Selected Index would also work but only until you change the order.
I am using a UIPickerView and currently their is only a single object in it. How can I display that single object on label.
It has this weird property that when we use pickerView the data is not set selected by default.Once we choose another object or roll it, then only any particular object is selected. Hence if only one object is their in pickerView. It does not count as selected even though when you tap on that single object.
I tried a lot but found that if their are more than one object then only you can display the selected object on label but not if their is only one object.
You need to make a code that is triggered when the UIPickerView changes, like this:
#pragma
-(void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
//Action that triggers following code:
{
NSString *nameString = [nameOnMutubaleArrayYouWannaGetDataFrom objectAtIndex:[picker selectedRowInComponent:0]]; //Or 1 if u have multiple rows
NSString *labelString = [[NSString alloc]initWithFormat:
#" %# ", nameString];
labelOutput.text = labelString;
Hope this helps.
I have a NSTextField which is nested by a custom view and I want to change the default behavior of multiple clicks in a row (double click, tripple click etc.), similarly to the behavior of text nodes MindNode (see the image below).
I want the first click to "activate" the text field and then go on from the beginning (like reseting the click count of the event).
I have following ideas, but I don't know how to implement them and if they actually make sense:
Somehow change the time using +[NSEvent doubleClickInterval] and slow down the second click.
Reduce the click count programmatically?
Make the NSTextField non-selectable using -hitTest:, forward the click to the superview, change some parameter of the text field and accept the next clicks. In this case, the click count of the second click is still 2.
Override -mouseDown: and not call super. This breaks the NSTextField's selection functionality.
I hope there is an easier way to achieve this, which I have overlooked.
Thanks for your answers!
Here is a graphical representation of the problem:
I would do this by embedding the text field and a custom view in an NSBox, which would be set to the custom type, initially with no background color or border (so it would be invisible). Initially, the custom view would be on top and it would have a mouseDown: method that would receive the first click. In that method you could rearrange the box's subviews so that the text field would then be on top and receive the next clicks. If you wanted, the box could be somewhat bigger than the text field so you could give it a background color or other drawing that would look like a custom activation ring around the text field. In the text field's controlTextDidEndEditing: method, you could reset the system back to the beginning state, so it would be ready for the next time you click on it.
After Edit: Here is the code I'm using in my overlay class:
#implementation Overlay
static NSComparisonResult rdComparator( NSView *view1, NSView *view2, void *context ) {
if ([view1 isKindOfClass:[NSTextField class]])
return NSOrderedDescending;
else if ([view2 isKindOfClass:[NSTextField class]])
return NSOrderedAscending;
return NSOrderedSame;
}
-(void)mouseDown:(NSEvent *)theEvent {
self.box.fillColor = [NSColor redColor];
NSView *contentView = self.box.subviews.lastObject;
[contentView sortSubviewsUsingFunction:rdComparator context:nil];
}
I've solved it by subclassing NSTextField and decrementing click count of mouse down events programmatically. Using a boolean property of the subclass I am able to turn this special behavior on and off.
- (void)mouseDown:(NSEvent *)theEvent
{
if (self.specialBehavior) {
theEvent = [NSEvent mouseEventWithType:theEvent.type
location:theEvent.locationInWindow
modifierFlags:theEvent.modifierFlags
timestamp:theEvent.timestamp
windowNumber:theEvent.windowNumber
context:theEvent.context
eventNumber:theEvent.eventNumber
clickCount:theEvent.clickCount - 1
pressure:theEvent.pressure];
}
[super mouseDown:theEvent];
}
To simplify this long method call, I wrote a category method for NSEvent which decrements the click count of an event.
How do I prevent a window title from displaying "Edited" for an NSDocument which is dirty?
I'm managing saving and autosaving myself, using a web service, and just don't want the distraction in the title bar.
I've tried overriding:
NSDocument's -isDocumentEdited and -hasUnautosavedChanges always to return NO.
-[NSWindowController setDocumentEdited] to do nothing, or always to use NO regardless of the parameter's actual value.
-[NSWindowController synchronizeWindowTitleWithDocumentName] to do nothing.
-[NSWindow setDocumentEdited] to do nothing, or always to use NO regardless of the parameter's actual value.
In all cases, the title bar still changes to Edited when I make changes to a saved document.
If I override -[NSDocument updateChangeCount:] and -[NSDocument updateChangeCountWithToken:forSaveOperation:] to do nothing, I can prevent this from happening, but it affects saving, autosaving, and other document behaviors, too.
I also tried this:
[[self.window standardWindowButton: NSWindowDocumentVersionsButton] setTitle:nil];
That displayed a blank string instead of Edited, but the dash still appeared – the one which normally separates the document name and Edited.
Any idea how to pry apart this part of the window from the document?
Several options:
To get a pointer to the "dash", look for a TextField in [window.contentView.superview.subviews] with a stringValue equals to "-". You can set its text to an empty string as well.
#implementation NSWindow (DashRetrivalMethod)
- (NSTextField*)versionsDashTextField
{
NSTextField* res = nil;
NSView* themeFrame = [self.contentView superview];
for (NSView* tmp in [themeFrame subviews])
{
if ([tmp isKindOfClass:[NSTextField class]])
{
if ([[(NSTextField*)tmp stringValue] isEqualToString:#"—"])
{
res = (NSTextField*)tmp;
break;
}
}
}
return res;
}
#end
You can override NSWindow's -setRepresentedURL:. This would also affect the NSWindowDocumentIconButton and the popup menu, but you can manually create it if you want by: [NSWindow standardWindowButton: NSWindowDocumentIconButton].
Override one of these three NSDocument's undocumented methods:
// Always return here NO if you don't want the version button to appear.
// This seems to be the cleanest options, besides the fact that you are
/// overriding a private method.
- (BOOL)_shouldShowAutosaveButtonForWindow:(NSWindow*)window;
// Call super with NO
- (void)_setShowAutosaveButton:(BOOL)flag;
// Here the button and the dash are actually created
- (void)_endVersionsButtonUpdates;
// Here Cocoa hide or unhide the edited button
- (void)_updateDocumentEditedAndAnimate:(BOOL)flag
Have you tried overriding NSDocuments - (BOOL)hasUnautosavedChanges in addition to overriding - (BOOL) isDocumentEdited?
Although this is a late answer, you can easily determine what is going to be the title of your NSDocument window by overriding
- (NSString *)windowTitleForDocumentDisplayName:(NSString *)displayName
in your NSWindowController and return the appropriate title.
You can do that also by overriding the property of your NSDocument:
- (NSString *)displayName
but this is not recommended by Apple, because that is normally used by the OS error handlers.
I added this answer, because none of the other answers really set me on the right path.
I'm working on a Core Data document application that dynamically creates NSTableColumns. The data cell type may be a checkbox, slider, etc. Programmatically binding to all cell types works, except for NSTextFieldCell.
All NSTextFieldCells fail to bind, and after editing they return to their default value. This happens no matter if they're binding to a string, a number (with an NSNumberFormatter applied), or a date (NSDateFormatter applied). I'm using the following format to do all bindings:
NSDictionary *textFieldOpts = [NSDictionary dictionaryWithObjectsAndKeys:#"YES", NSContinuouslyUpdatesValueBindingOption, #"YES", NSValidatesImmediatelyBindingOption, nil];
[aCell bind:#"value" toObject:[[entryAC arrangedObjects] objectAtIndex:0] withKeyPath:#"numberData" options:textFieldOpts];
Again, these statements work if the cell type is anything but an NSTextFieldCell.
I threw in an -observeValueForKeyPath method to log when the value changes... and for other cell types (NSSliderCell for instance) I can see the value changing, but with the NSTextFieldCell, it never, ever updates.
Turns out that I needed to implement the NSTableView data source method setObjectValue to manually get the change from the NSTableView (View) and then manually set the data in the array controller (Model) similar to the code below:
- (void)tableView:(NSTableView *)aTableView setObjectValue:(id)anObject forTableColumn:(NSTableColumn *)aTableColumn row:(NSInteger)rowIndex {
[[[entryAC arrangedObjects] objectAtIndex:rowIndex] setValue:(NSNumber *)anObject forKey:#"numberData"];
}
For some reason, the bindings to NSTextFieldCells, when set programmatically on a cell-by-cell basis, only work one way: to display the data only. Personally I would classify this as a bug...