I have built a large IOS app and whilst testing noticed that a uiScrollview within a static page has stopped scrolling - to explain the setup of the page - the structure is as follows -
the scrollview is connected to the header file as scwollMa (as in above doc).
it has the following properties in storyboard -
I have applied the following into the .m page -
- (void)viewDidLoad
{
[super viewDidLoad];
//Set Scroller
[_scwollMa setScrollEnabled:YES];
self.scwollMa.contentSize = CGSizeMake(320, 1100);
Yet it does nothing! no error either - big head scratcher! Any advice at all?
You have set the height of the scrollview at the same height as the content size. To scroll set the height of the scroll view to fit into the visible screen area (like self.view.frame.size.height).
If the scroll view and the content view have the same height, there's nothing to scroll for.
contentSize.Height must be greater to actual.height:
Change the following line of code to
self.scwollMa.contentSize = CGSizeMake(320, 1500);
will work for you.
and in interface builder keep height which is visible inside your view.
Related
I have a scrollview where I have added different views (like tutorial).
What I wanted to have is slider with below design where on scroll I will see previous tut on left side and next on right side.
For this what I have added is scrollview with paging enabled and adding UILabel (for now) in for loop. After adding label in scrollview below is what I had.
To see the data on the left & right, what I did is uncheck clip subviews from storyboard.
However what I noticed is I can scroll only in scrollview area and not outside.
Any idea how can I make UILabel make scrolling outside & inside scrollview.
As of now to make it working, what I have done is added swipe gesture on view and making scrolling programmatically. However what I was looking is if I scroll outside scrollview, it should scroll scrollview little too.
Phewww...
Finally I managed to make it done..
What I did is added one more scrollview (dummyScrollView) with full screen width above main scrollview (mainScrollView) (which I am using to show label).
Now I enabled paging for the dummyScrollView too and implement below where I am scrolling my mainScrollView based on the factor calculation for the dummyScrollView
#pragma mark - UIScrollView Delegate
- (void) scrollViewDidScroll:(UIScrollView *)sender
{
float myFactor = 0;
// 44232 is tag for new scrollview
if (sender.tag==44232) {
myFactor = mainScrollView.frame.size.width/duplicateSV.frame.size.width;
myFactor = duplicateSV.contentOffset.x*myFac;
CGRect mCC = CGRectMake(myFactor, 0, mainScrollView.frame.size.width, mainScrollView.frame.size.height);
[mainScrollView scrollRectToVisible:mCC animated:NO]; // NO is very important... YES will not work
}
// 44231 is main scrollview tag where I won't be doing anything...
if (sender.tag==44231) {
}
}
I'm loading a view from a storyboard programatically, but there's an issue with my subview heights (I'm using Autoresize Subviews etc).
When the view loads, the main UIView appears to be the correct size, but the subviews that depend on the constraints to dynamically calculate their final height don't seem to be resizing from the sizes they were set at in interface builder.
Loading the view like so:
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
ApplicationRecordingViewController* recordingController = (ApplicationRecordingViewController*)[storyboard instantiateViewControllerWithIdentifier:#"recordView2"];
[self presentViewController:recordingController animated:NO completion:nil];
Orange area's height is from top of main view to top of grey area. Grey area is fixed height
The strange thing is, if I set the simulated size in interface builder as the correct view for my phone, the sizes work out. I guess the initial heights for subviews are 'baked' into the view, but then (usually) resized when the view actually loads?
Note: The orange area should be completely filled by the camera view I'm loading into it.
Incorrect height
Correct height if I change simulated layout
Would love to know what I'm doing wrong!
Edit 1: Constraints
Camera is the orange bit. The Camera bottom constraint is currently set as the bottom of the view + enough room for the gray bar. Have also tried setting the bottom to match the top of the gray bar!
Link to Storyboard with Scene
I know you're all better than me, but I experienced the same in my last project. My Camera View inside a UIView is not in full screen or resizing and fitting the whole UIView, and I also posted it on my daily blog.
Implement viewDidLayoutSubviews -- Inside that method, layout again your video preview layer.Do not alloc init anything inside that method, just re-layout your views. After that, your video preview will fill the height and width of its parent, or whatever you've been targetting.
The issue also has something to do with the hierarchy of the constraints and views.
You already got the answer.
'if I set the simulated size in interface builder as the correct view for my phone, the sizes work out.'
You may call some functions to get height in viewDidLoad or viewWillAppear.
Change Code like this
- (void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
[self.view setNeedsLayout];
[self.view layoutIfNeeded];
CGFloat height = [self getHeight];
}
or
- (void) viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
CGFloat height = [self getHeight];
}
As i can see in your storyboard constrain you have set bottom space to bottom layout guide 150 . i think this is the issue . if you give fixed height to bottom view then no need to set constant as from bottom layout guide --> 150 .
Your old constrain :- >
Just set bottom space of orangeview from greenview = 0.
Check new constrain ,
Here is your storyboard link ,
Storyboard Download link
Here is your output,
After investigating the layout a little more, I found the camera view (orange) seemed to be the correct size, but the live camera preview wasn't.
Solution was to move the camera library (SCRecorder)'s init method into viewDidAppear (was in viewDidLoad before).
My thinking is iOS doesn't autolayout the camera preview view in the same way as normal UIViews, etc.
#interface ApplicationRecordingViewController () {
SCRecorder *_recorder;
}
#end
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
_recorder.previewView = _previewView;
}
Perhaps you can try to get rid of these two hook.
I have two questions related to UITableViews.
1) The first one is, what is the gap at the top of the UITableView? My app always starts with the top cell not flush with the top of the tableview (as shown in the second image), it starts about one cell lower, i.e. where that gap is in the interface builder. I can't find where that is coming from, or why.
2) I can't seem to resize the uitableview programmatically, I'm trying to reduce the height after a popup appears. I've shown an example of it not working in the second picture.
Here is (an example of) what I am trying at the moment:
- (void)viewDidLoad
{
[super viewDidLoad];
self.table_view.delegate = self;
CGRect tableBounds = self.table_view.bounds;
tableBounds.size.height -= 100;
self.table_view.bounds = tableBounds;
CGRect tableFrame = self.table_view.frame;
tableBounds.size.height -= 100;
self.table_view.frame = tableFrame;
}
Thanks!
UITableView Selected:
Simulation:
In your xib (or storyboard) put your UITableView at position (0,0). ( the same position as the navigation bar).
The first image shows that your table view has problems even in Interface Builder. It looks as if you've set the top inset incorrectly; check your edge insets.
The reason your resizing code is not working is probably that it is too early (viewDidLoad); put it in viewDidAppear: and see if that works, and if it does, try moving it back to viewWillAppear: so the user doesn't see the resizing. If it doesn't work, it might be because you're using auto layout; you can't manually alter the frame of something whose frame is dictated by auto layout. (Your resizing code is also silly; you want to set the frame, not the bounds.) But it might also be because you're using a UITableViewController in a UINavigationController; if you do that, the table view is under the navigation controller's direct control and its size is not up to you.
My problem are:
I implement a UIScrollView (DrawView)to draw something on it(Task is ok).
I drag a ScrollView to ViewController using storyboard and assign DrawView class to it.
I using pink gesture to zoom one element in DrawView, it is correct, but when element out of size DrawView i cant scroll it to see part of element.
In file ViewController.m
- (void)viewDidLoad
{
[super viewDidLoad];
[self.drawingView setScrollEnabled:YES];
[self.drawingView setContentSize:CGSizeMake(100, 200)];
}
Can you give me way to solution problem or some tutorial same?
Thank for all
Sorry for bad grammar
Set content size of the scrollView as the size of the element which you are adding to it.
Say elementView is the view that you are adding to scroll view then,
[self.drawingView setContentSize:elementView.size];
According to your comment, drawingview size is 700x900 which is less than your content size 100 x 200. That's why, it couldn't get scroll. Content size should be greater than size, then only it will get scroll even scrolling enabled.
I want to have a text title scroll above a text view, but can't find information on how to do it. I've been looking for days, but can't even figure out how to look for the info. I want the function to work like the Apple Notes app where the date text is positioned above the text entry location and scrolls off the screen with the text but is not editable.
I've tried placing labels above UITextView, but the label does not scroll with the textView. I have a sample Xcode project I'm work with, but not sure if it can be uploaded for others to see what I'm doing. I almost had success with the project, but the labels only scroll with the text in the landscape view, not the portrait view for some reason.
I've read Apple developer docs on TextViews and several other sources without finding any discussion on how to do this or examples to follow.
Can anyone point me in the right direction?
I'm sure there must be a better way to do this, but this is the only approach I've found to work after more than a week of trying to find a solution. If I can figure out how to upload the entire Xcode example project I will do that.
This is the explanation of the approach I found to work under iOS 6.1 and Xcode 4.5. I have only tired this on the iPhone 6.1 simulator.
After creating a full screen text view and placing a label at the top of the text view,
To get the label to scroll off screen with the editable text view you need to:
turn off autolayout in interface builder (uncheck Use Autolayout). (there appears to be a problem with autoLayout and scrollViews in iOS 6.x)
turn off the text view scrolling in interface builder (uncheck Scrolling Enabled)
set the text view content insets height (Top) to the label height
embed the text view and label in a scroll view.
set properties for the scroll view and text view to be able to access their properties
in viewDidAppear:animated:
a. set the scroll view content size height to 20 plus the greater of the screen view height or the text view content height plus the label height
b. set the text view delegate to self
-(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
float screenHeight = self.view.bounds.size.height;
// set the scroll view content height to 20 plus the greater of the view height or the text view content size height plus the label height
screenHeight = MAX(screenHeight, self.textView.contentSize.height + 20);
self.scrollView.contentSize = CGSizeMake(self.view.bounds.size.width, 20 + screenHeight);
// set the text view delegate
self.textView.delegate = self;
}
set the text view height dynamically in textView delegate method textViewDidChange:
a. if the text view content height is greater than the view bounds height less the label height:
1. set the text view frame to the view bounds width and the text view content height plus the lable height
2. set the scroll view content height to the view bounds width and the text view bounds height plus the label height
// dynamically set the text view content size height
-(void) textViewDidChange:(UITextView *)textView {
if (self.textView.contentSize.height > self.view.bounds.size.height - 20) {
self.textView.frame = CGRectMake(0.0, 0.0, self.view.bounds.size.width, self.textView.contentSize.height + 20);
self.scrollView.contentSize = CGSizeMake(self.view.bounds.size.width, self.textView.bounds.size.height + 20);
}
}
set the struts and springs in interface builder
1. set the scroll view and text view struts for left, right and bottom
2. set the scroll view and text view springs for width and height
3. set the label struts for left, right and top
4. set the label spring for width
The same settings need to be made every time the view changes orientations.
There might be a way to do this by setting constraints in code under autolayout, but I barely understand constraints, much less setting them successfully in code.
Hope this helps someone else.
What you are looking for is called UIScrollView. Take a look at the Apple documentation here.
A good tutorial on UIScrollView can be found on the Ray Wenderlich site.