I'm rather new to programming in Cocoa, but I've been working on learning the language quite diligently up until I hit this snag that I can't seem to circumvent/hack my way around, (not that I'd want to. I'd prefer to do it right!)
Where I stand, In IB I have a toolbar that has a button and what I'm trying to do is mimic the maps app. I want to be able to press the button and then have my location pop up, while keeping the button selected, then when it's pressed again, deselect it and thus remove the blue blip location from the map.
ideally, I would like to use the following code, but the if statement doesn't seem to want to work on the simulator (which I presume wouldn't change if I tried on the iPhone.)
-(IBAction) showLocation: (id) sender
{
if([sender isSelected]) // this doesn't work!!
{
[sender setSelected:NO];
mapView.showsUserLocation = FALSE;
}
else
{
[sender setSelected:YES];
mapView.showsUserLocation = TRUE;
}
}
obviously if I get rid of the if statement, I know that I can show the location and set the selected as I liked, but I can't seem to "get" the selected property from the button... what's the right way of doing this?
try
- (void)methodName:(UIButton *)sender
{
if (sender.selected == YES) ...
Related
I have search and can't find any information so I would like some help here. I am new to Xcode and objective c. I have 10 NSButtons set in Interface Builder to be Push On Push Off type. I am trying to figure out how when one of the buttons is clicked and highlighted, how do I unhightlight the other nine. I am use to Java, in java you can just make an if statement to turn off the highlight of the buttons not clicked. In IB I don't see how to send a message to the other buttons because I don't know their "names" or addresses. Can you please help me figure this out, explain it or send me to a link or video. Thank you.
This is what I've used in the past.
Create an NSArray with all your buttons in it, something like:
NSArray* buttons = #[button1, button2, button3, button4];
Then create a method like this.
- (void) toggleButtons: (id) sender {
for (Button *item in buttons) {
if (item == sender) {
item.selected = !item.selected;
} else {
item.button.selected = NO;
}
}
}
Now call it from each of your button handlers:
- (IBAction) handleButton1:(id) sender {
[self toggleButtons:sender];
<...rest of your code...>
}
I'm using the doubleClickAction of a NSTableView to display a NSPopover. Something like this:
NSInteger selectedRow = [dataTableView clickedRow];
NSInteger selectedColumn = [dataTableView clickedColumn];
// If something was not selected, then we cannot display anything.
if(selectedRow < 0 || selectedColumn < 0)
{
NSLog(#"Invalid selected (%ld,%ld)", selectedRow, selectedColumn);
return;
} // End of something was not selected
// Setup our view controller, make sure if there was already a popover displayed, that we kill that one off first. Finally create and display our new popover.
DataInspectorViewController * controller =
[[DataInspectorViewController alloc] initWithNibName: #"DataInspectorViewController"
bundle: nil];
if(nil != dataPreviewPopover)
{
[dataPreviewPopover close];
} // End of popover was already visible
dataPreviewPopover = [[NSPopover alloc] init];
[dataPreviewPopover setContentSize:NSMakeSize(400.0f, 400.0f)];
[dataPreviewPopover setContentViewController:controller];
[dataPreviewPopover setAnimates:YES];
[dataPreviewPopover showRelativeToRect: [dataTableView frameOfCellAtColumn: selectedColumn row: selectedRow]
ofView: dataTableView
preferredEdge: NSMinYEdge];
Which works just fine. My popovers get created and removed on the cells that I double click on . The problem is, I want to the popover to go away if I click anywhere outside of it (like a single click on another cell). I have been looking around, but for the life of me cannot figure out how to do it.
This is something I would assume is built into a popover, (I'm fairly certain it was in the iOS UIPopoverController class) so I'm just wondering if im missing something simple.
You need to change the property behavior of your popover (in code or on interface builder) to:
popover.behavior = NSPopover.Behavior.transient;
NSPopover.Behavior.transient
The system will close the popover when the user interacts with a user interface element outside the popover.
Read more about this in Apple's documentation.
the .transient flag doesn't work for me.
However I can make things work by the following:
1) Whenever I show my popover I make sure I activate the app
(my app is a menu-bar app, so this doesn't happen automatically)
NSApp.activate(ignoringOtherApps: true)
2) When I click outside the app, then my app will be deactivated. I can detect this in the AppDelegate
func applicationWillResignActive(_ notification: Notification) {
print("resign active")
}
and act accordingly
After calling show(relativeTo:of:preferredEdge:) method,
Add below line
popover.contentViewController?.view.window?.makeKey()
And make sure you set
popover.behavior = .transient
Sorry, I've added solution in Swift.
While transient worked for most cases, it was an issue when the user interacted with elements outside of the application, as the popover would hide but not close.
What finally ended working for me was:
popover.behavior = .semitransient
Now the popover closes when changing app, or interacting with any other element outside of the app. But will not close when interacting with a NSMenu, and maybe won't close either with other interactions.
Quoting from the documentation for NSPopover.Behavior.semitransient:
The exact interactions that cause semi-transient popovers to close are not specified.
Similar to the documentation for NSPopover.Behavior.transient:
The exact interactions that will cause transient popovers to close are not specified.
I am kind of new to IOS app development. I have a map view and when a user taps on the MKMapView, i want to pop a text box there so that user can tag the place. I figured out the part on how to handle tap events on map. But I couldn't really understand how to get the textbox up there on map. I think I should use overlays, but I am not sure how to put a text box in an overlay. Can someone please give me sample code to put textbox in overlay?
Here is my code which handles tap events and this overlay display might have to go in the if loop.
-(void)handleTapOnMap:(UITapGestureRecognizer*)sender
{
if (sender.state == UIGestureRecognizerStateRecognized)
{
NSLog(#"Tapped on the map");
return;
}
else {
return;
}
}
If you want to add custom overlays you can see this project on overlays on github
Or if you want to add the overlay yourself you will have to create a custom view and use the delegate method :
- (MKOverlayView *)mapView:(MKMapView *)mapView viewForOverlay:(id )overlay
{
yourOverLayView *view = [[[yourOverLayView alloc] initWithOverlay:overlay] autorelease];
return view;
}
You can also go through the mkmapview tutorial :
I'm using a UIPanGestureRecognizer to recognize horizontal sliding in a UITableView (on a cell to be precise, though it is added to the table itself). However, this gesture recognizer obviously steals the touches from the table. I already got the pangesturerecognizer to recognize horizontal sliding and then snap to that; but if the user starts by sliding vertical, it should pass all events from that touch to the tableview.
One thing i have tried was disabling the recognizer, but then it wouldn't scroll untill the next touch event. So i'd need it to pass the event right away then.
Another thing i tried was making it scroll myself, but then you will miss the persistent speed after stopping the touch.
Heres some code:
//In the viewdidload method
UIPanGestureRecognizer *slideRecognizer = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(sliding:)];
[myTable addGestureRecognizer:slideRecognizer];
-(void)sliding:(UIPanGestureRecognizer *)recognizer
{
if (recognizer.state == UIGestureRecognizerStateBegan)
{
CGPoint translation = [recognizer translationInView:favoritesTable];
if (sqrt(translation.x*translation.x)/sqrt(translation.y*translation.y)>1) {
horizontalScrolling = YES; //BOOL declared in the header file
NSLog(#"horizontal");
//And some code to determine what cell is being scrolled:
CGPoint slideLocation = [recognizer locationInView:myTable];
slidingCell = [myTable indexPathForRowAtPoint:slideLocation];
if (slidingCell.row == 0) {
slidingCell = nil;
}
}
else
{
NSLog(#"cancel");
}
if (recognizer.state == UIGestureRecognizerStateEnded || recognizer.state == UIGestureRecognizerStateCancelled)
{
horizontalScrolling = NO;
}
if (horizontalScrolling)
{
//Perform some code
}
else
{
//Maybe pass the touch from here; It's panning vertically
}
}
So, any advice on how to pass the touches?
Addition: I also thought to maybe subclass the tableview's gesture recognizer method, to first check if it's horizontal; However, then i would need the original code, i suppose... No idea if Apple will have problems with it.
Also: I didn't subclass the UITableView(controller), just the cells. This code is in the viewcontroller which holds the table ;)
I had the same issue and came up with a solution that works with the UIPanGestureRecognizer.
In contrast to Erik I've added the UIPanGestureRecognizer to the cell directly, as I need just one particular cell at once to support the pan. But I guess this should work for Erik's case as well.
Here's the code.
- (BOOL)gestureRecognizerShouldBegin:(UIPanGestureRecognizer *)gestureRecognizer
{
UIView *cell = [gestureRecognizer view];
CGPoint translation = [gestureRecognizer translationInView:[cell superview]];
// Check for horizontal gesture
if (fabsf(translation.x) > fabsf(translation.y))
{
return YES;
}
return NO;
}
The calculation for the horizontal gesture is copied form Erik's code – I've tested this with iOS 4.3.
Edit:
I've found out that this implementation prevents the "swipe-to-delete" gesture. To regain that behavior I've added check for the velocity of the gesture to the if-statement above.
if ([gestureRecognizer velocityInView:cell].x < 600 && sqrt(translate...
After playing a bit on my device I came up with a velocity of 500 to 600 which offers in my opinion the best user experience for the transition between the pan and the swipe-to-delete gesture.
My answer is the same as Florian Mielke's, but I've simplified and corrected it some.
How to use:
Simply give your UIPanGestureRecognizer a delegate (UIGestureRecognizerDelegate). For example:
UIPanGestureRecognizer *panner = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(panDetected:)];
panner.delegate = self;
[self addGestureRecognizer:panner];
Then have that delegate implement the following method:
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer {
CGPoint translation = [(UIPanGestureRecognizer *)gestureRecognizer translationInView:gestureRecognizer.view.superview];
return fabsf(translation.x) > fabsf(translation.y);
}
Maybe you can use the UISwipeGestureRecognizer instead? You can tell it to ignore up/down swipes via the direction property.
You may try using the touch events manually instead of the gesture recognizers. Always passing the event back to the tableview except when you finally recognize the swipe gesture.
Every class that inherits from UIResponder will have the four touch functions (began, ended, canceled, and moved). So the simplest way to "forward" a call is to handle it in your class and then call it explicitly on the next object that you would want to handle it (but you should make sure to check if the object responds to the message first with respondsToSelector: since it is an optional function ). This way, you can detect whatever events you want and also allow the normal touch interaction with whatever other elements need it.
Thanks for the tips! I eventually went for a UITableView subclass, where i check if the movement is horizontal (in which case i use my custom behaviour), and else call [super touchesMoved: withEvent:];.
However, i still don't really get why this works. I checked, and super is a UITableView. It appears i still don't fully understand how this hierarchy works. Can someone try and explain?
I have a NSTableView as a very central part of my Application and want it to integrate more with the rest of it. It has only one column (it's a list) and I draw all Cells (normal NSTextFieldCells) myself.
The first problem is the highlighting. I draw the highlight myself and want to get rid of the blue background. I now fill the whole cell with the original background color to hide the blue background, but this looks bad when dragging the cell around. I tried overriding highlight:withFrame:inView: and highlightColorWithFrame:inView: of NSCell but nothing happened. How can I disable automatic highlighting?
I also want all rows/cells to be deselected when I click somewhere outside my NSTableView. Since the background / highlight of the selected cell turns gray there must be an event for this, but I can't find it. I let my cells expand on a double click and may need to undo this. So getting rid of the gray highlight is not enough.
EDIT: I add a subview to the NSTableView when a cell gets double clicked and then resignFirstResponder of the NSTableView gets called. I tried this:
- (BOOL)resignFirstResponder
{
if (![[self subviews] containsObject:[[self window] firstResponder]])
{
[self deselectAll:self];
...
}
return YES;
}
Besides that it's not working I would need to implement this method for all objects in the view hierarchy. Is there an other solution to find out when the first responder leaves a certain view hierarchy?
I wanted to achieve a similar solution (with an NSOutlineView but this has no difference): when clicking inside the outline view BUT not in a row with a cell (for instance at the empty bottom of a source list), I wanted the currently selected row to be deselected. I ended up with this little piece of code that might be of some help.
In a NSOutlineView subclass, I've put:
#implementation ClickOutlineView
- (void)mouseDown:(NSEvent *)theEvent
{
NSPoint pointInWindow = [theEvent locationInWindow];
NSPoint pointInOutlineView = [self convertPoint:pointInWindow toView:nil];
int rowIndex = [self rowAtPoint:pointInOutlineView];
if ([theEvent clickCount] == 1 && rowIndex == -1) {
[self deselectAll:nil];
}
else {
[super mouseDown:theEvent];
}
}
#end
No doubt it's too late to help the question's poster, but this may help others who come across this on Google (as I did).
You can prevent row selection by selecting 'None' in the 'Highlight' drop-down menu, in the attributes inspector in Xcode 4.
There is also an answer on SO here for setting this programmatically.
Overloading -highlight:withFrame:inView: should be correct. How did you do the overload? Does an NSLog() statement indicate that your code is running? You should also look at NSTableView's -highlightSelectionInClipRect:, which may be more convenient for this.
In order to do something (such as unselect the current selection) when the user clicks outside the table view, overload -resignFirstResponder on NSTableView.