Dragging a touch along a row of UIButtons - iphone

I have a row of say 10 UIButtons along the bottom of the iPhone screen. The user can TouchUpInside each of these. I'd also like to allow the user to drag their finger along the row, deselecting the previous button that was touched when the finger is over the next. This kind of behaviour is seen on iPhone's keyboard.
The obvious thing to try is UIControlEventDragOutside or UIControlEventDragExit to trigger the appropriate actions however these only work when the touch event is sufficiently far away from the button. As my buttons must sit flush against each other this is not good enough for me.
Suggestions?

Related

button highlight state and gestures

I've been struggling with this for a while already and some
help would be useful.
Imagine I have a UIButton, which starts in highlighted/selected state.
If a user taps it, then highlighted/selected state changes.
I've implemented this and it works fine. Problems start
for example if user taps inside the button region,
does not release her/his finger, and moves mouse
outside the button area -- at this time my Button
would usually lose highlighted/selected state.
Anyway, I have solved this issue too, by overriding UIControlEventTouchUpOutside
and making button keep the state it had before...
But now another problem comes in, similar to the above,
if a user taps the button, does not release his/her
finger, and moves the finger to the right say (horizontally,
which also makes my dialog for instance go to the right),
then I again lose "selected/highlighted" state....
I believe again some kind of gesture similar to - but different -
than UIControlEventTouchUpOutside is being called which
removes my selected state...
Do you know what can be going in here? Any advice appreciated.
ps. I have fixed all the issues by just setting different images
for normal/selected states using the interface builder.
For the highlighted effect you can use the: setHighlighted of UIButton class.
When you start touching the button set the highlighted property of button to YES.
when you start touch:
yourButton.highlighted = YES;
When you stop touch:
yourButton.highlighted = NO;
I have fixed all the issues by just setting different images for normal/selected states using the interface builder.

ccTouchesMoved and selector:#selector(ButtonTapped:)

Ill try and keep this as simple as possible.
I have a guy which you drag around the screen
I have a shoot button which fires bullets
To drag the guy around the screen im using ccTouchesMoved, basically get the users finger movement and set the guy to that place. Done.
I have a button which is a CCMenuItemImage and if it is tapped then is called a selector to run a method. The method simply fires some bullets. Done.
Now my problem is i cant have these two things work at the same time. I would like the player to be able to drag around the guy and shoot at the same time. Im assuming the button is not being tapped becuase the user is touching and dragging around the player.
How can i fix this? Still be able to drag around with one finger and press the shoot button with the other and they both work together?
You might want to implement your fire button using a sprite. You can handle ccTouchesBegan and ccTouchesEnded to check for a press within the bounds of your button, to swap it with a pressed state (on begin) or to implement the fire action (on end).
In your ccTouchesMoved handler, you can iterate over the set of touches and determine if the touch that moved is the one over the button, or the touch that should change the character position.

Cocoa Touch - Handling touches that get interrupted or lost

I have a couple places in my app where UI elements reset themselves when a touch ends on them. For example, hiding a dashed outline, sliding a view back to the default position.
The problem is that on occasion the app loses track of the touches. One example is if I slide the view upward and cause a UIAlertView to show, the view doesn't slide back, because the reset code is in touches ended. The touch ends during the time the UIAlertView is active, and the view doesn't reset. The same example works for hiding the dashed outlines.
My question is, where/how can I handle the reseting of these custom UI elements so that when a touch ends without being noticed it will still reset. TouchesEnded isn't always doing it for me.
Have you try touchesCancelled? I think it is called when the touch get interrupted.
EDIT: If this doesn't work then maybe you can manually add code that cancel the touch when you initiate the alert.

I have a UI Scroll View with UIButtons on top. How do i make it scroll when they touch and drag the buttons?

I want something similar to how the iPhone homescreen works. I have my scrollview inside my main view, which scrolls to the right, but when you touch on the UIButtons, they become highlighted and dragging means they don't end up getting pressed but also the scrollview doesn't end up scrolling. It doesn't do this on the homescreen. How can i make it similar to this?
A touch-down-drag is a completely different event. Apple doesn't support this directly—you'd have to code it in—start tracking the touches using the gesture responders as soon as a touch-down-inside is detected, then scroll the same amount, and stop scrolling at a touch-up-outside (or inside). This would most likely fall under the category of unusual use of interface elements, and could very well get you rejected.
I think this is a better answer to the question:
UIScrollview with UIButtons - how to recreate springboard?

Handling UITableCell move left (or move right) event?

I want to creat an UITableView which each cell (UITableCell) in this table can be moved left or moved right (System will be notified when user touchs down the cell and moves finger to left or right). Anybody can tell me how can i do it :) Thanks :)
I want to build a Table which each TableCell in it become a menu likes image bellow when user touch up TableCell and move finger to left or right!
I would guess this is done by watching for the touch events, being the first responder and monitor all touch events before you send them further to the UITableView under.
I think there is a source code from Apple that shows this.. think it's called Gestures or TableView Gestures... do a search on the Apple site.
Also, do read on the UIGestureRecognizer docs from the SDK. These can be attached to a certain view, I read.
Good luck, let us know if you're successful.