Paging in uitableview - iphone

I am using a UITableview.In that there are nearly 100 records.I want to show 10 records at a time after that i will click on a button or UIPageControl which will show the next 10 records.So,please suggest me how can i do it?

If you just wanna create a table like that you could follow the below outlines.
In your button click Append or change the data in your data source array of your tableview. (Depending upon your requirement)
[self.myDataSourceArray addObjects:#"obj", #"obj2", nil];
Reload the table
[self.tableView reloadData];
UPDATE FOR THE COMMENT:
OK let me add some code,
//Consider this method is called when you click the next button
- (void)nextButtonAction
{
//Remove the older objects
[self.myDataSourceArray removeAllObjects];
//Add your new objects to the array
[self.myDataSourceArray addObjects:#"obj", #"obj2", nil];
//Reload the table
[self.tableView reloadData];
}

You could have a forward and backward button in the navigation bar with the page number

Define a rect would you like to scroll and then call method scrollRectToVisible:newRect for UITableView
CGRect newRect = CGRectMake(0, 0, tableView.frame.size.width, tableViewCell.height*10);
[tableView scrollRectToVisible:newRect animated:YES];

I am not sure if it is a good thing to introduce a pagination mechanism in your case. Because a UITableView should be fine for handling around 100 records. Just think of your Addressbook which can easily contain more than 100 records.
If you have a big number of records in a UITableView filtering and the index on the right with the letters of the Alphabet can help you to quickly navigate to the desired entry.
However, if you do decide to add more records to one table a common practize is to add a "Load more entries" cell at the very bottom of the table view.
For Example: Check out the Top50 Apps in the AppStore-App.

This really goes against Apple's User Interface Guidelines. TableViews are designed with built in highly efficient pagination (reusable cells). I have TableViews with 4000 records and when the data model behind the TV is done right, it can be very responsive.
If you are dead set on this, you could use a button on the NavBar, Toolbar, etc and use that to call scrollToRowAtIndexPath.

you can keep a count of the number of times the button is pressed
int i=0;
-(void)buttonPressed{
i=i+10;
[table reloadData];
}
then in
cellForRowAtIndexPath
{
cell.textLabel.text = [NSString stringWithFormat:#"%#",[Arr objectAtIndex:i+indexPath.row]];
}

Related

constant tableviewcell at the beginning of the tableview

I would like to know if there is any sneaky way of getting a UITableViewCell to appear at the beginning of a UITableView no matter what the array that is going to populate the tableview contains?
I am having issues where I would like to have a "select all" cell at the top of the tableview but currently having issues trying to adjust the arrays I have going into the tableView:cellForRowAtIndexPath:
Not sure of your end goal, but there are many ways some easier (sneaky ways) than others depending on your needs. It sounds like your items are fairly static, so you can just insert them before you display or update the table row.
say you have a datasource called self.items and you did something to get data. Maybe in your app you are round tripping to some data source based upon input, like sort selectors or from the search bar delegate.
try something like this in the area where you load your datasource.
NSString *myCustomObject = #"Jump To Songs";
self.items = [self getGetMovieList];
[self.items insertObject:myCustomObject atIndex:0];
[self.tableView reloadData];
Another easy way would be to add sections to your table and just make the first section your navigation items.
Note: you may need to handle the actions in didSelectRowAtIndexPath......
there you go, not so sneaky, but pretty simple.
be well
You can make two types of UITableViewCell, then return the "select all" one if indexPath.row == 0.
On the other hand, how about just make a UIView for the "select all" functionality, and set it as the tableHeaderView of your table view?

How to handle references to UITextFields in dynamic UITableView (iPhone)

I have a UITableView that is broken up into a user defined number of sections. Within each of these sections there are always 2 rows. Each of these two rows contains a UITextField which the user is able to edit.
What I need is a way of being able to access the data in these UITextFields at a later point. I was hoping it would be a simple problem however it's causing me a great deal of grief.
So far I have tried two approaches:
Attempt 1
I created two NSMutableArrays in which I added the UITextField objects to at index i (corresponding to the section it came from). I then tried to access the values by iterating through the array. This didn't work since the UITextFields kept getting wiped clean. Every-time I scroll down the table and the UITextField is out of view, when I go back it's contents have been wiped clean.
Attempt 2
I tried to get hold of the number of sections in the UITableView (this was fine). I then wanted to iterate through each section of the UITableView, recording the values in the rows of each. This is where I became unstuck since I'm not sure how to do this or if it's even possible.
I apologise if this is a naive question to ask, however I'm really struggling and would appreciate any advice.
Keep in mind that the text fields get reused as you scroll, so you don't really want to store references to them.
What you do instead, is to capture the information as it is entered. The easiest way to do this is to implement the textFieldDidEndEditing protocol method in the delegate.
The tricky part is figuring out which row the text field is in. The best way is to create a UITableViewCell subclass which has a NSIndexPath property. You can then set that when you configure the cell with tableview:willDisplayCell:forRowAtIndexPath:.
Then, in textFieldDidEndEditing, access the tableViewCell indexPath property through its superview. i.e.:
NSIndexPath indexPathOfParentCell = [(MyUITableViewCellSubclass *)self.superview indexPath];
Doing it this way allows you to know both the section and row of the cell.
Create your TextField in the cellForRow of the Table like so and give it a tag
UITextField * userField = [[[UITextField alloc] initWithFrame:CGRectMake(0, 12, self.view.frame.size.width -20, 20)] autorelease];
userField.tag = 1001;
userField.font = [UIFont fontWithName:#"HelveticaNeue-Bold" size:14];
userField.textAlignment = UITextAlignmentCenter;
userField.delegate = self;
userField.autocorrectionType = UITextAutocorrectionTypeNo;
userField.autocapitalizationType = UITextAutocapitalizationTypeNone;
userField.clearButtonMode = UITextFieldViewModeWhileEditing;
if (indexPath.row == 0)
[cell.contentView addSubview:userField];
then access the TextField like so:
UITextField *userField = (UITextField *)[[(UITableViewCell *)[(UITableView *)tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:0]] contentView] viewWithTag:1001];
Your "Attempt 1" should work OK if you keep the text field's text in your arrays rather than the text field itself. (Anything that tries to make a view or control into a data object has a good chance of going wrong.)
Whatever acts as a data source for your table view should be able to re-populate the scrolled cells according to section and row if the content is stored separately.

How to fill UITableView after Initialization

I read tutorial here
http://adeem.me/blog/2009/05/19/iphone-programming-tutorial-part-1-uitableview-using-nsarray/
which shows how to fill a UITableView at initialization. I can't find tut to do so after initialization (for example when User has clicked on a button).
Any suggestion ?
You would just update the data source and reload the table view.
Following that tutorial, you would do it like so:
- (IBAction)myButtonPressed:(id)sender
{
self.arrayData = [[NSArray alloc] initWithObjects:#"iPhone", #"iPod", #"MacBook", #"MacBook Pro", #"iMac"];
[self.tblSimpleTable reloadData]
}
This will tell the UITableView to reload the data source and adjust the amount of sections, rows etc.
Note that you might prefer to use a NSMutableArray instead.
[self.mutableArrayData addObject:#"iMac"];

How to add data in UITableview at run time?

I want to add data or cells in UITableview when we scrolled to the last cell of the UITableView. In other words, as we have seen in many iPhone apps, that when we reached to the last cell of the UITableview the more cells get added to it at runtime. I want to achieve that functionality in my project.
Means Add some more cells to the UITableview when we reached to the previously added last cell.
Please tell me the sample code or any tutorial for it.
I think that there are 2 questions here.
First, how to detect the end of tableVeiw? Second, how to add cells dynamically?
First question, I think it can be done by observing the value of content offset of scrollView or current indexPath of tableView cell. The content offset of scrollView can be observed by following method of UIScrollViewDelegate. The content offset is a property of scrollView.
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
CGFloat currentOffset = scrollView.contentOffset;
// Detect scrolling to bottom by this offset value.
....
}
The index of cell may be decided by the method of UITableViewDataSource.
- (UITableViewCell *)cellForRowAtIndexPath:(NSIndexPath *)indexPath
Second question can be overwhelmed by the methods of UITableView.
beginUpdates
endUpdates
insertRowsAtIndexPaths:withRowAnimation:
deleteRowsAtIndexPaths:withRowAnimation:
insertSections:withRowAnimation:
deleteSections:withRowAnimation:
I remember the sample codes in this official document will teach how to use above methods. They don't reload all cells, but careless operations will result in crash easily.
If you have data stored in an array, then you would definitely have the count of how many cells you want.
Use the below code for your help
-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{ return [array count];}
i believe this would have helped you.
Populate the tableView by using an array (as you should always do). When the delegate method cellForRowAtIndexPath ask your for the last cell, repopulate your array with new (more) data and make a [tableView reloadData].
you just want to add data in table?
Then, first you may need to add one more view, modal view. You should write some specification about what you want to add in this view.
Next you send a message to existing data array(Assume you use array)
[ExistingArrayData addObject:TemporalilyNewObject];
And you can sort the data by using NSSortDescriptor.
NSSortDescriptor *nameSorter = [[NSSortDescriptor alloc] initWithKey:KEY_VALUE ascending:YES selector:#selector(caseInsensitiveCompare:)];
[ExistingArrayData sortUsingDescriptors:[NSArray arrayWithObject:nameSorter]];
In this case, this method sorts the data by KEY_VALUE, ascending.
Finally, you shoule add this code in RootView's viewWillAppear method.
[self.tableView reloadData];
This code notifies app of change of data.
-(void) tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath{
int i=0;
i=indexPath.row;
int count=[urTablearray count];
if (count == (++i)) {
//do ur stuff here
here add object to urTablearray
[urTablearray addObject:#"vijay"];
}
}
Note: urTablearray is NSMutableArray type not NSArray

how to add smooth scroll to UITbaleview when we adding new row to table view

i am getting images with messages from .net webserver by giving xml input.
that's working fine.
i am sending request for every 3 sec and if any new messages and images are there i just add those messages and images to the array and reload the table view.
That is also fine,But what i need is when i reload table view when ever there is new messages that will be displayed on table view by smooth scrolling the existing row.
same as twitter.
can any one please help me.
Thank u in advance.
if you know the indexPath of newly added row , you could use the below function of UITableView to scroll upto new row with animation (smooth effect).
- (void)scrollToRowAtIndexPath:(NSIndexPath *)indexPath atScrollPosition:(UITableViewScrollPosition)scrollPosition animated:(BOOL)animated
Instead Of completely reloading the table, you should call insertRowsAtIndexPaths:withRowAnimation:
The second option will let you specify how you want it animated
(this will also be much more efficient than reloading all the data every time)
You can do something like the following:
(this makes the assumptions that recievedImageFrom server will be called after the data has already been loaded into the data source object. Also, myDataSourceArray is the array where the data is being stored for the table and myTableView is the UITableView.
-(void)recievedImageFromServer
{
NSUInteger row = [myDataSourceArray count]-1; // This can also be set to 0 if you want
// to insert at the top of the table
NSIndexPath* newIndex = [NSIndexPath indexPathWithIndex:row];
[myTableView insertRowsAtIndexPaths:[NSArray arrayWithObject:newIndex]
withRowAnimation:UITableViewRowAnimationTop];
}
It will then request the cell from its data source.