hi i am working with NSTableView in my app.
I want to display grid lines depending on the number of rows but it shows many lines even when the number of rows are very less.
Is this a usual behavior?
Or am i doing something wrong?
I have checked the horizontal grid lines option from xib.
cannot understand how to achieve this using code.
What I found to work best for me so far is the following code.
Just fool the original grid drawing code to draw only on populated rows.
Subclass NSTableView, if needed and override drawGridInClipRect:(NSRect)clipRect as following:
- (void)drawGridInClipRect:(NSRect)clipRect
{
NSRect lastRowRect = [self rectOfRow:[self numberOfRows]-1];
NSRect myClipRect = NSMakeRect(0, 0, lastRowRect.size.width, NSMaxY(lastRowRect));
NSRect finalClipRect = NSIntersectionRect(clipRect, myClipRect);
[super drawGridInClipRect:finalClipRect];
}
If I understood your issue I may say: "YES". It's expected from the NSTableView to be fulfilled of stripes even when empty if you set it so.
I realize that you want also to manage those lines programmatically. Consider check out this method setGridStyleMask: on the NSTableView Class Reference.
Good luck.
Related
I'm trying to make a rotation on a tableview to tilt the table (to give the effect of a 3d text crawl similar to the star wars opening crawl).
After looking around I found this question objective-с CALayer UIView real rotation
and the accepted answer seems to do what I want, however when I apply the code to my TableView it does nothing and the table appears as usual.
This is the code I am copying:
float distance = 50;
CATransform3D basicTrans = CATransform3DIdentity;
basicTrans.m34 = 1.0 / -distance;
_tableView.layer.transform = CATransform3DRotate(basicTrans, M_PI_4, 1.0f, 0.0f, 0.0f);
I'm placing this in my viewDidLoad method after creating my array of Strings (that populate the tableView)
I currently only have three other methods in the Controller:
didReceiveMemoryWarning (automatically addd when project created)
tableView: numberOfRowsInSelection (used for setting up the table view)
tableView: cellForRowAtIndexPath (used for setting up the table view and setting the cells text form the array)
My understanding is that the tableview has a CALayer, and that the CATransform3D manipulates this to give the representation of the view in a 3d space. If my understanding is correct then I don't get why the list is shown normally on screen? I appreciate the numbers my not give the effect I want yet but they should at lest effect the appearance of the tableView on screen.
Also I have imported QuartzCore etc and added it in linked frameworks
Solution is to use the code marked as OLD answer in the the - (UITableViewCell *)tableView: cellForRowAtIndexPath: method after the cell is checked for being null.
Since the approach suggested below has not worked, another thing I would try out is applying the transform to the UITableView's subviews. Actually, UITableView is a UIScrollView, so it is just a container for subviews that make up the real content of the table view. I would try something like this:
for (UIView* subview in tableView.subviews) {
subview.layer.transform = ...;
}
I have never inspected a table view subviews hierarchy, so I cannot say whether this will work or you should rather apply the transform to just one of the subviews, but I hope this can lead you in the right direction.
OLD ANSWER:
You could try setting your table view's layer sublayerTransform instead of `transform':
You typically use this property to add perspective and other viewing effects to embedded layers. You add perspective by setting the sublayer transform to the desired projection matrix. The default value of this property is the identity transform.
(source).
I am suggesting this based on the hypothesis that a UITableView has quite a complex structure in terms of subviews, so transforming just the view's layer might have no effect. I haven't tried it, though, so I cannot guarantee it will work.
I am working on TV guide project, I want to know how to form a grid i.e I want to split the cells and construct it just like a grid. I know that I have to use UITableview, but I want to know how to do it.
If any one please provide the concept with sample project or code will be appreciated.
You can use custom cells, each cell with some around 4 to 5 buttons based on your requirement.
I hope you have idea on creating custom table cells & using them.
providing code is bit clumsy thing here
I have implemented something like this before, my approach was to subclass UIScrollView and implement some custom view recycling and layout. It was pretty simple to implement, although things got a bit complicated when I started implementing animations. Basically, the idea is to override - (void)layoutSubviews with something like:
- (void)layoutSubviews
{
[super layoutSubviews];
CGRect visibleBounds = [self bounds];
// calculate the range of visible views
// recycle any no longer visible views
// for any missing views, request them from the data source
}
You will need to implement your own data source and delegate protocols for whatever needs you have, mine were pretty simple.
This sort of project already exists look into AQGridView.
The Transporter iPhone app does this in a great way; you can check out their code on GitHub here.
Here's what the tableview looks like in their app:
I am trying to setup a NSTableView with a custom cell using an ArrayController and Bindings. To accomplish this I added a subview to the custom cell. The data connection seems to work somewhat. Though, there seems to be a redraw problem which I cannot fix. When I load the application only some of the cells are rendered. When I scroll through the rows or select one the rendering changes.
I created an example project on github to illustrate what the problem is.
The actual source code for the cell rendering can be found here:
// CustomCell.m
- (void)drawInteriorWithFrame:(NSRect)cellFrame inView:(NSView*)controlView {
if (![m_view superview]) {
[controlView addSubview:m_view];
}
// The array controller only gets wrapped data items pack by the NSObjectTransformer.
// Therefore, objectValue returns a NSObjectWrapper.
// Unpack the wrapper to retreive the data item.
DataItem* dataItem = [(NSObjectWrapper*)[self objectValue] original];
[[m_view name] setStringValue:dataItem.name];
[[m_view occupation] setStringValue:dataItem.occupation];
[m_view setFrame:cellFrame];
}
It seems as if the parent controlView does not redraw. Can I force it somehow?
This is almost certainly not a best practice way of doing this, and I'll explain why afterwards: however, it does seem to work. Replace your cell class's drawInteriorWithFrame:inView: method with the following:
- (void)drawInteriorWithFrame:(NSRect)cellFrame inView:(NSView*)controlView {
DataItem* dataItem = [(NSObjectWrapper*)[self objectValue] original];
[[m_view name] setStringValue:dataItem.name];
[[m_view occupation] setStringValue:dataItem.occupation];
[m_view setFrame:cellFrame];
NSData *d = [m_view dataWithPDFInsideRect:[m_view bounds]];
NSImage *i = [[NSImage alloc] initWithData:d];
[i setFlipped:YES];
[i drawInRect:cellFrame fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1.0];
}
The problem is that only one NSCell is created for the entire table. That's how cells are meant to work: the table view creates a cell, and calls setObject… followed by drawInterior… over and over again to get the cell to draw the whole table. That's great from an efficiency perspective (the NSCell class was designed back when 25mhz was a fast computer, so it aimed to minimise the number of object allocations), but causes problems here.
In your code, you populate a view with values, and set its frame, adding it as a subview of the table view if needed. However, since you've only got one instance of NSCell, there can only be one view: you took the single view that you had and merely moved it down the rows of the table.
To do this properly, you'd need some data structure to track all the views you added as subviews of your NSTableView, and when the cell is updating one in the drawInterior… method you'd need to look up which the correct one was and update that. You'd also need to allocate all these views in code (or at least move the view to a separate nib which you could load multiple copies of), because as it is you've only got one in your nib and copying a view is a pain.
The code I wrote is a kludge, since it's really inefficient. What I did was each time the view needs to draw, I drew the view into an off screen image buffer, and then drew the buffer into the correct place in the table view. In doing so, I avoided the problem of only having one view, since the code just takes and draws a new copy of its contents whenever it is needed.
EDIT: See my other answer for explanation
Have you implemented copyWithZone:? You'll need to ensure you either copy or recreate your view in that method, otherwise different cells will end up sharing a view (because NSTableView copies its cells).
I'm working on an an app that updates both a UITableView and a UIScrollView. I like how UITableView updating works. As I add, remove, or update items, I call insertRowsAtIndexPaths:withRowAnimation:, reloadRowsAtIndexPaths:withRowAnimation:, and deleteRowsAtIndexPaths:withRowAnimation: as appropriate. However, updating the UIScrollView has turned out to be more of a challenge.
So how can I do it? My UIScrollView contains images, and I want to be able to insert, update, and remove individual images -- with animation -- efficiently and smoothly, and perhaps in random order. How does one do this sort of thing?
As an example, I have code like this in my UIScrollViewDelegate implementation for adding a new image:
if (newImageindex == currentImageIndex) {
[scrollView setNeedsDisplay];
[scrollView setContentOffset:portalView.contentOffset animated:YES];
} else if (newImageIndex < currentImageIndex) {
currentImageIndex++;
CGPoint offset = portalView.contentOffset;
offset.x += portalView.frame.size.width;
portalView.contentOffset = offset;
}
This is close, I think, but not quite right. I end up with the images added, but the UIScrollView seems to scroll to a position before the first image in the view. If I start scrolling it by hand, the first image appears. It's like it's scrolled to position -1 in my images.
The example may not help to highlight my problem much, but surely it's a common need to dynamically rejigger the images appearing in a UIScrollView. What's the state of the art on this?
A UIScrollView is not so specialized and structured as a UITableView. The former is a generic view that scrolls and zooms anything you put in it, and you can put any subviews into it anywhere, whereas the latter is made especially to display lists of cells stacked on top of each other.
So the answer is: you need to animate the subviews in the scrollview yourself. There are various libraries like Three20 which provide frameworks for creating more advanced views, you'll need to use a suitable component from one of those or roll your own.
I am new to iPhone programming and working on my first real application (i.e. one not written in a book or online) and I've run into a small problem which I could solve a multitude of ways, but feel like there should be a good solution that perhaps I am just missing.
Here is the scenario: I have a UITableView with a bunch of standard UITableViewCells in it. What I want to do is toggle a green check mark when the cell is selected and I have that part working (note: I'm already using the accessoryType for something else, so I can't use it for the checkmark...besides, it's not as pretty). Unfortunately, when I toggle the checkmark like so:
if (...) {
cell.imageView.image = [UIImage imageNamed:#"checkmark.png"];
} else {
cell.imageView.image = nil;
}
It makes the cell's label bounce back and forth depending on whether it is checked or not. What is the proper way to align the cell's text (set via cell.textLabel.text) regardless of whether or not it has an image set? The solutions I have come up with are:
Create a blank 40x40 png image in Photoshop and set the unchecked to that
Create a blank 40x40 image solely in code
Set some setting that I don't know about that will align it for me
Create a subclass of UITableCellView that does what I need (which would be stupid, I'd just go with option 1...)
Suggestions? Thoughts? Comments? Thank you very much :-)
P.S. I'd like the solution to work with OS 3.0 and 4.0 if that makes any sort of difference.
Option 1 is the way to go for a standard cell.
Strictly speaking, you do not have to subclass UITableViewCell to customize the layout. You can add any views you wish to the contentView. So you can add a UILabel and UIImageView to the contentView instead of using the imageView and textLabel properties.