I´m new trying to make some apps using objective c, so I´ve an idea using uitableview but I don't imagine how can I get this.
I´m trying to do something like you do in a spreadsheet where you have a fixed header and the first column too
So when scroll the uitableview vertically the header will stay visible at top of the table and rows will change
And finally when you scroll in horizontal direction the first cell of the row will stay visible and will change the header depending of how you scroll the uitableview
I hope you could give me an idea how to get this, because I don't imagine how to do this, also I don´t have a lot of experience with this programming language.
Thanks!
In a non-grouped table, section headers "stick" at the top of the table as the table scrolls. You can provide a custom UIView (or sub-class thereof) for a section header through the delegate method –tableView:viewForHeaderInSection:. This header view could be created on-the-fly programmatically or loaded from a NIB file. Either way, you can have it contain whatever you want, even update it as the app runs (provided you have given yourself access through ivars or class variables to the views contained in your header view.) If you go this route, you'll want to be clever about allocating resources that comprise this view, so that you are not constantly allocating new resources! This delegate method can be called frequently, and on all but the first call you could simply return the previously created (but updated as and if necessary) header view.
UITableView isn't designed to do this, although I am sure you could figure out some way eventually.
My approach would be to use a fixed UIView of some sort (possibly a UILabel, etc) in a UIViewController's nib as the header/locked cell, and add the UITableView under that. You couldn't then use a UITableViewController, but would have to implement the delegate and dataSource methods in your UIViewController, and use a UISwipeGestureRecognizer to pick up the gestures from the tableView and update the other views.
I've done this by adding a UIView that mimics the first cell in my table. In my case I am using a subclass of UITableViewCell, but that is perhaps not relevant. Normally this view is hidden with an alpha of 0.
If you view controller is the delegate of the UITableView then it will also be the delegate for the inherited UIScrollView. So in your view controller you can implement scrollViewDidScroll. When the scrollView's contentOffset is positive I set my custom view's alpha to 1 (I also do some small size tweaks to make sure there is a perfect match), and when the contentOffset returns to 0 or negative, I reset the alpha back to 0.
prepend the first row of data in your array to what ever in the first row is your headings, put the text in bold with attributed text, It wont be sticky but you will have headings...
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I am building an app that requires a tableview control so that users can select multiple rows and act upon them in some way. I find it easy to load my data and display it using the UITableViewController but it seems when I do it this way I am unable to place any other controls on the page, such as a toolbar to give the user some actions to perform on the selected rows. I can place a toolbar control on the form in the storyboard, but it doesn't render in the emulator.
Using a UIViewController and placing a TableView on it seems to come with its own set of confusing challenges (that will make total sense once I conquer them).
Is there any advice for a smooth way of getting a table view with toolbar controls? Thanks!
don't use a TableViewController. Use a Standard ViewController, then add a UITableView to it, and adjust the size. This way you will be able to do whatever else you want on that view without limiting yourself to the tableView only functionality.
When you do this make sure you add the datasource and delegate to the connected table. Then add cellForRowAtIndex, number of sections, number of rows, and whatever other delegate methods you need for your table.
Good luck
Is there any advice for a smooth way of getting a table view with toolbar controls?
Yes there are few ways to accomplish this, one way would be adding a footerview to your tableviewcontroller check these
http://developer.apple.com/
UIButtons on tableFooterView not responding to events
Easier way to add this is using storyboard.
Just drag and drop a view in to your tableviewcontroller, then you can adjust the views size and put anything from objects menu to inside of the view.
Now the problem with that is view will not be stable position at the bottom of the page like a tabbar. Lets say you have only 1 row in your tableview, footer view will go up just below that 1 row, lets say you have hundreds of items in your tableview toolbar will be at the bottom of the rows.
The other solutions for your problem would be either create a custom view and adding it to current view or window (this is little bit adbance),but if you want this just google it.
Or just as you said, create a viewcontroller and put a uitableview inside. Dont forget to add <UITableViewDelegate,UITableViewDataSource> to your .h file and then you can call UItableview delegate methods.\
Good Luck.
For a simple example lets say I have a UITextView with a Button underneath it. These two controls are siblings both embedded in a parent UIView.
I now change the text within the UITextView and resize it accordingly. Is there a way to make the button automatically move to have the same relative distance to the bottom of the UITextView? This may seem trivial for this case, but I will have a longer hierarchy with multiple UITextViews that change and it would be nice not to have to calculate the height of every object manually.
One way to approach this would be with a table view: if you place each of your text views within its own table view cell, the table view will automatically calculate its total height from individual calls to its delegate’s -tableView:heightForRowAtIndexPath: method and lay itself out accordingly. Whenever the height of one of your text views needs to change, you can call -reloadData on the table view to make it lay itself out again. A disadvantage of this approach is that it’s really difficult to animate the height changes; if that’s essential to the effect you’re going for, I’m afraid you’re stuck with doing the entire layout manually.
Try the autoresizingMask property of UIView.
I need to create a screen that scrolls vertically - like the tableview but I need 3 columns and within those 3 columns I need to add images of varying height - so this will not fit into rows that a tableview can provide.
Should I create 3 tableviews and lay them out side by side - or something else. I think I could build this by simply positioning the images using coordinates but I wanted to benefit from methods that the table view can provide.
If you want the columns to act stuck together, so that they all scroll simultaneously, then I think best approach is to use UIScrollView with the images added in the correct placed "by hand." UITableView and friends is not built to handle non-lined up columns.
added If you do use a UIScrollView, and you have a large number of images you want to display (that is, the user can scroll for a long time), then it would be wise to recycle your UIImageView objects that are scrolled off the screen. This is what UITableView does with UITableViewCell objects, and that's why UITableView wins. You can win, too, if you code carefully.
Three table views would work, but in order to keep things neat and from the same datasource, I would consider using a subclassed UIPickerView and the UIPickerViewDelegate/UIPickerViewDataSource.
Particularly necessary methods:
// UIPickerViewDataSource
– numberOfComponentsInPickerView:
– pickerView:numberOfRowsInComponent:
// UIPickerViewDelegate
– pickerView:rowHeightForComponent:
- pickerView:viewForRow:forComponent:reusingView:
According to my opinion You should have to take three UITableView in xib file and take its IBOutlet then give each UITableView an unique tag and then implement UITableView's Delegate methods and in that Methods Check for Tag and then assign values.
Along With this, the other solution, you can also use UIPickerView and then implement UIPickerView's delegate methods also..
Happy Coding !!!
I have several parts in my app where I use custom table view cells.
Their content is created with subviews.
The problem is that on some of these cells, the content does not appear at all or does not appear correctly until after the cell was selected for the first time.
One example is a custom cell which has a custom subview which can be set after its creation. This view does not appear at all before I selected the cell and its views were redrawn. Calling -[setNeedsDisplay] in the subview's setter method does not help either.
The problems was that I was using the cells themselves to calculate their height. For some reason, the subviews (which were part of the cell used to calculate the height) weren't appearing correctly in the cells that were used for the actual displaying.
Therefore my advice: Never use a UITableViewCell to calculate its own height. This may work in principle (it doesn't crash), but might bite you later in unexptected and hard-to-debug ways.
I have a UIView (created in IB) with a grouped UITableView as a subview. Below this table view is a UIButton. The XIB containing the view will be loaded by a few different viewcontrollers, and so the contents of the table view can vary between one and four cells.
Here's what I want to achieve: when the view loads, the height of the tableview (tableView.frame.size.height) should be adjusted depending on the number of cells, and the button should be placed just beneath the table view.
Can this be done? Could it somehow be done if the view is created programmatically?
Thanks in advance
Edit: Pxl's suggestion was just what I was looking for. A while later, the need arose to have more than just a button below the table view - this was accomplished by creating a separate view containing everything I needed, and implementing the tableView:viewForFooterInSection: and tableView:heightForFooterInSection: functions.
A note for those of you trying to do the same thing: the tableview has to be programmatically created if you want different heights for the footers, or footers for only some of the sections. This is because the footer height set in IB will override the one returned from the tableView:heightForFooterInSection: function.
if there are only a handful of rows, may i suggest that you create a special UITableViewCell that contains just a button?
then make that button cell the bottom row of the last group all the time. make the group so that it will be unlabeled and appear as if the button is sitting at the bottom of your tableview. this way you won't have to muck around with recalculating the tableview's frame and redrawing it.
if the tableview will scroll due to there being many rows, then you'd be calculating the height of the tableview up to a set max (at which point the tableview will need to scroll to show more rows).
once you've determined the height of the tableview you'll need to display your rows, make a frame of the appropriate size, set the tableview's frame to it, position the button just under the tableview, and then redraw the view.
the layout and positioning in this case will need to be done programmatically.
UITableview is a subclass of UIView, so you can change its frame to suit your needs just like a UIView, and UITableView will manage drawing itself to whatever frame you give it.
Just use the methods UITableViewDataSource and UITableViewDelegate provides you.
height = [self tableView:numberOfRowsInSection]*[self tableView:heightForRowAtIndexPath:] + A_CONSTANT_FOR_HEADER_AND_FOOTER_HEIGHT
I agree with pxl that adding a cell with the button in it may be the easiest way to accomplish what you want.
Whether or not you do that, the table view's sizeToFit method should resize the view to (just) fit its contents. If that doesn't work, you can use numberOfSections and rectForSection: to build a loop that determines the height of the table's contents, and reset its frame manually. (And then position the button underneath.)