Height of UIScrollView get changed? - objective-c

I am adding UITableView and UIButton in UIScrollView. button is placed below tableview.
Well, when i select any row from table it add a button on that row and every thing is ok till now, but when i click that row second time it remove button added on it but the problem is that along with removing that button it also scroll my table up and button bellow the table reside on its place ie. it leaves gap between table and button.
my table is reloaded every time when a row is clicked.
code for add UIButtonbelow the UITableView
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
mainTable.frame = CGRectMake(mainTable.frame.origin.x, mainTable.frame.origin.y,
mainTable.frame.size.width,
([menuItemsArray count] * 60) + 380);
[scrollView setContentSize:CGSizeMake(320,([menuItemsArray count] * 60) + 80 + 350)];
reserverBtnBottom = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[reserverBtnBottom setFrame:CGRectMake(20.0f,mainTable.frame.size.height,280, 40)];
[reserverBtnBottom addTarget:self action:#selector(reserveBtnAction) forControlEvents:UIControlEventTouchUpInside];
[reserverBtnBottom setBackgroundImage:[UIImage imageNamed:#"normal.png"] forState:UIControlStateNormal];
[reserverBtnBottom setAlpha:1];
[reserverBtnBottom setTitle:#"Reserve this table" forState:UIControlStateNormal];
[reserverBtnBottom setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
[scrollView addSubview:reserverBtnBottom];
rest thing goes here
}
What am i missing?
Thanks in advance.

heightForRowAtIndexPath is a bad place for such calculation, as you are changing a single row state this method might be called once to calculate the new height. When it is called the cell still has an old height value, so does the table.
The button position calculation should be moved to layoutSubviews: method of the table and button superview which is a scrollView in your example. The way it should work is that the superview recalculates all the subviews frames once any of them changes it's frame.
Sometimes instead of overriding the layoutSubviews: the frame calculation is handled with the viewController , that's what you were trying to do but you did it in a wrong way. You'll need to find a better place for the frame calculation if you don't want to override scrollView layoutSubviews:.
If you only need the scrollView to add the button below the table, it would be better from my experience to get rid of the scroll view (at least because you do have scroll view in another scroll view which is Never a good practice) and add the button to the table footerView. The footer view is displayed below the table and scrolls together with it.

After long time i resolve my problem. put this code in viewWillAppear instead heightForRowAtIndexPath-
mainTable.frame = CGRectMake(mainTable.frame.origin.x, mainTable.frame.origin.y,
mainTable.frame.size.width,
([menuItemsArray count] * 60) + 380);
[scrollView setContentSize:CGSizeMake(320,([menuItemsArray count] * 60) + 80 + 350)];
and move my reserveBtnBottom to footer of UITableView.
Thanks to A-Live for his great help.

Related

Set a UIPickerView to bottom of UITableview regardless of scroll position

I'd like to present a UIPickerView snapped to the bottom of a UITableView regardless of where it is scrolled.
Currently I have a UIPickerView added to a UITableView that I present when a button is pressed, but when I scroll the table the UIPickerView goes out of view, and if I'm scrolled out of range of where I've presented it, the UIPickerView appears to have never been called.
Does anyone know how to accomplish this?
Thank
The use of UITableViewController is great unless you need to add subview that don't scroll with the table view. It can't really be done. The solution is to use a UIViewController instead and add your own table view, setup the table view dataSource and delegate protocols and replicate the basic table view controller plumbing.
Once your view controller works like a normal table view controller again, you can now add subviews to the view controller's view that won't scroll with the table.
if u add tableview programatically
SearchtableView.frame = CGRectMake(450, 90, 318, 600);
SearchtableView = [[UITableView alloc] initWithFrame:CGRectMake(623, 90, 400, 400)style:UITableViewStyleGrouped];
[self.view addSubview:SearchtableView];
//belove the tableview//
//Add UIPickerView to the self.view]//
Something told me that there must be a simpler alternative to the answers that I'd been given, and I found a solution.
I decided to find the y coordinate of the scroll point using scrollViewDidScroll: and then animating the UIPickerView to the desired location.
...
[UIView beginAnimations:nil context:NULL];
CGFloat pointY = self.scrollPoint.y;
[self.sortPicker setFrame:CGRectMake(0, pointY + 200, 320, 216)];
[UIView commitAnimations];
...
The UIPickerView will only appear if the scroll has been stopped so it's necessary to implement a method to stop the scroll on touch:
- (void)stopScroll:(UITableView *)tableview
{
CGPoint offset = tableview.contentOffset;
[tableview setContentOffset:offset animated:NO];
}
This will allow you to display and dismiss the UIPickerView at any moment at any given destination.

UIButton not clickable after UITableView scrolled

I have a UITableView which is populated with some cells. I have created a UIButton using the following snippet, it is placed next to one of the section headers.
UIButton *addButton = [UIButton buttonWithType:UIButtonTypeCustom];
[addButton addTarget:self action:#selector(addButtonPressed) forControlEvents:UIControlEventTouchUpInside];
[addButton setBackgroundImage:[UIImage imageNamed:#"add.png"] forState:UIControlStateNormal];
addButton.backgroundColor = [UIColor clearColor];
addButton.frame = CGRectMake(270, 150, 29, 29);
The button is placed and works correctly. However, after the view is scrolled (even slightly - like 1 pixel), the button works once and then ceases to respond. When it fails to respond the action for when it is clicked is not triggered and the button doesn't give the 'depressed' shadow. The rest of the application runs as normal and it does not crash.
This seems odd because after I scroll the button is clickable once more before it stops working. The button is used to insert rows into the table, so after it is pressed there is an extra row, possibly this is breaking the bounds or something?
Button pressed function:
- (void)addButtonPressed {
self.addClientTable.editing = YES;
// First figure out how many sections there are
NSInteger lastSectionIndex = [self numberOfSectionsInTableView:self.addClientTable] - 1;
// Then grab the number of rows in the last section
NSInteger lastRowIndex = [self.addClientTable numberOfRowsInSection:lastSectionIndex];
[self.addClientTable insertRowsAtIndexPaths:[NSArray arrayWithObject:[NSIndexPath indexPathForRow:lastRowIndex inSection:lastSectionIndex]] withRowAnimation:UITableViewRowAnimationRight];
self.addClientTable.editing = NO;
}
Where addClientTable is the UITableView.
What could cause a UIButton to stop responding to clicks and where in my scenario would this be caused by?
I am almost sure that your problem is that your button is out of it superview, and you are not using the clip subviews option in your view that contains the button, or in one of it superviews.
Set to true all the views property clip subviews and see if it appears your button. (We expect that the button disappear)
If you provide more code I can try to help you to solve this problem.
-
Reading again your question, another probable problem to it is that you have one view in front of your button. You can test it changing the background of your view, or something like that.

How to add an image in UITableView's content view while we reodering cells?

I have a tableview where I provide the option to reoder the cells. But, I don't want to show the delete icon when the user doing rearranging cells. So I did like this to remove the delete button.
In normal mode..
After edit mode (That is, non deletable but rearrangable mode)..
Here, two things are happening. One is the accessoryview of each cell has a image(that represents rearrangement). Second thing is, all strings are moved some points from the left screen. This gap is actually for the deletion symbol. Since I hide the delete button, an empty space appears.
Ok, here is the problem comes. I now want to add some custom button with an image in each cell's content view.
So, I added the following code in my tableView: cellForRowAtIndexPath:
if (isEditable)
{
selectionButton = [UIButton buttonWithType:UIButtonTypeCustom];
UIImage *img = [UIImage imageNamed:#"blue_button.png"];
selectionButton.frame = CGRectMake(-25, 10, img.size.width, img.size.height);
[selectionButton setBackgroundImage:img forState:UIControlStateNormal];
[selectionButton addTarget:self action:#selector(buttonClickAction:) forControlEvents:UIControlEventTouchUpInside];
[cell.contentView addSubview:selectionButton];
}
The blue button was 24*24 pixels.
The reason why I used -25 as "x" value:
If I give a positive value or zero, the button will overlapped with cell text. Below image represents when the x value is 0.
But for x=-25,
What I need:
Since I added the button with negative x value, the whole image width (24 pixels) will be hiden in the x value (25 pixels). So the button action buttonClickAction: was not called. I want to change the image when the user tapping on it(switching between selected/unselected mode).
Is there any way to call the button's action method? Or should I create a custom cell?
Just confused..
Add this to your Table View Controller
- (BOOL) tableView:(UITableView *)tableView shouldIndentWhileEditingRowAtIndexPath:(NSIndexPath *)indexPath {
return NO;
}
It will remove empty space.

UIScrollView not scrolling when adding item in IB and code

When I create a Scrollview on my scene, and then add a button to scene in IB. Then I go into the code, set the content size, enable user interaction and add another button. When I run the program in the simulator the Scrollview does not work, if I remove the button that is in IB on the scene it works just fine. Is it not possible to add items to the scrollview both in IB and programmatically?
EDIT: I thought it may be something in the app I already had. So I decided that I would create anew project and all it has in it is code, and the scene picture below. It is indeed added below the ScrollView.
UIButton *myButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[myButton setTitle:#"My Button" forState:UIControlStateNormal];
myButton.frame = CGRectMake(100, 100, 150, 50);
[scrollView addSubview:myButton];
scrollView.userInteractionEnabled = YES;
[scrollView setContentSize:CGSizeMake(320, 1000)];
Here your scrollView is not scrolling due to the autoLayout, uncheck the auto Layout if you are not using.
I Just made a similar to your requirement. It is working fine, and after allowing autoLayout it just stopped scrolling.
The auto layout constraints fits to the visible part of the screen, if the objects in scrollView are more then screen size, it will scroll.
So my suggestion if you are not using autoLayout just uncheck it, and works fine.
Here is an helpful link: http://developer.apple.com/library/ios/#releasenotes/General/RN-iOSSDK-6_0/_index.html#//apple_ref/doc/uid/TP40012166-CH1-SW19
Basically what this says is that, with auto-layout you don't and shouldn't have to use setContentSize:. Instead your inner view should have it's edges snapped to the edges of the scrollview. Let me demonstrate how I solved it.
scrollBackground : a view that contains every other view that needs to scroll in the scrollview.
[scrollview addSubview:scrollBackground];
[scrollview addConstraints:[NSLayoutConstraint
constraintsWithVisualFormat:#"V:|[scrollBackground(1000.0f)]|"
options:0 metrics:nil
views:NSDictionaryOfVariableBindings(scrollBackground)]];
[scrollview addConstraints:[NSLayoutConstraint
constraintsWithVisualFormat:#"H:|[scrollBackground(==scrollview)]|"
options:0 metrics:nil
views:NSDictionaryOfVariableBindings(scrollBackground)]];
The key here being those | at beginning and end of the VisualFormat String. These will tell the scrollview what is the contentSize. Of course if you have a contentSize smaller than the frame size of the scrollview it won't scroll in that direction. In my example this is true for width. It only scrolls up and down.
Make sure you set your content size in viewDidLoad or at some point after the view has already been loaded from the nib file.
As vishy Pointed out, your Button should be part of the ScrollView's Hierarchy, else you'll just be scrolling an empty view.
In the case you posted, the scrollview will not scroll because all of the content is visible. Try changing that last line to:
[scrollView setContentSize:CGSizeMake(50, 50)];
and it will start scrolling, because the content size is smaller than all of the content in the view.
check d2burke answer in this question
you should place your code in viewWillLayoutSubviews instead of viewDidAppear

Adding a button (UIButton) to a custom tableview cell drawn with drawRect:

I am currently working a on project where I have lots of custom table view cells. Part of the requirements is that the cells be able to expand if their default size can not hold all of the content. If they need to be able to expand I have to add a UIButton to the cell and when it is tapped redraw it in a bigger view where all the data fits. Currently in draw rect I essentially do this:
if([self needsExpansion]) {
[self addExpansionButton];
}
-(void)addExpansionButton {
self.accessoryButton = [UIButton buttonWithType:UIButtonTypeCustom];
[self.accessoryButton setShowsTouchWhenHighlighted:YES];
UIImage *buttonImage = [UIImage imageNamed:#"blue_arrow_collaps_icon.png"];
[self.accessoryButton setFrame:CGRectMake(280, 82, buttonImage.size.width, buttonImage.size.height)];
[self.accessoryButton setImage:buttonImage forState:UIControlStateNormal];
[self.accessoryButton addTarget:self action:#selector(toggleExpanded) forControlEvents:UIControlEventTouchUpInside];
[self addSubview:self.accessoryButton];
}
This works fine, except for when I click anywhere else in the cell the button flickers and disappears. Anyone know how to propertly do this?
From the UITableViewCell Class Reference:
You have two ways of extending the
standard UITableViewCell object beyond
the given styles. To create cells with
multiple, variously formatted and
sized strings and images for content,
you can get the cell's content view
(through its contentView property) and
add subviews to it.
Instead of adding the accessory button as a subview of the UITableViewCell, you should add it as a subview of the contentView:
[[self contentView] addSubview:self.accessoryButton];
Have you worked out the following problem in your design approach?: Let's say one of your cells (let's call it A) determines it needs expansion, so you add a button to it. What happens when the user scrolls through the UITableView? For performance reasons, your UITableView delegate should be using dequeueReusableCellWithIdentifier in tableView:cellForRowAtIndexPath:. So you'll be reusing A to display a different row of the table. Do you really want A to have an accessory button? Probably not, since it's now representing a different object.
You're probably better off doing the cell customization at the UITextViewDelegate. In tableView:cellForRowAtIndexPath:, you can determine if the object being displayed at the row specified needs a button, and if it does add it as a subview to the contentView.
Then again, if your table size is always relatively small (say < 50), you can use this approach Jeremy Hunt Schoenherr suggests.