Hey Simple little app for educational purposes, its a simple uitableview and I want users to be able to use a uislider to adjust the font size as needed. The code I have now works to change the font but only when the view is updated, ie when i pull up or down the table view to reveal other cells. I'd like the font change to be reflected immediately as a user moves the uislider if possible, here's the code that I have working half way:
-(UITableViewCell *) tableView: (UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *) indexPath {
static NSString *SimpleTableIdentifier = #"SimpleTableIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier: SimpleTableIdentifier];
if (cell == nil)
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier: SimpleTableIdentifier] autorelease];
NSUInteger row = [indexPath row];
cell.text = [listData objectAtIndex:row];
UIImage *image = [UIImage imageNamed:#"star.png"];
cell.font = [UIFont systemFontOfSize:[fontSlider value]];
cell.image = image;
return cell;
}
You could make an IBAction for the fontSlider for the "Value Changed" option as follows:
-(IBAction) refreshResize
{
[self.view setNeedsDisplay];
}
That should work. setNeedsDisplay refreshes the screen.
Related
Im working on Multiple checkbox Functionality in tableview, I have to search in google finally i got it one solution.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
}
if ([selectedRowsArray containsObject:[contentArray objectAtIndex:indexPath.row]]) {
cell.imageView.image = [UIImage imageNamed:#"checked.png"];
}
else {
cell.imageView.image = [UIImage imageNamed:#"unchecked.png"];
}
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleChecking:)];
[cell.imageView addGestureRecognizer:tap];
cell.imageView.userInteractionEnabled = YES; //added based on #John 's comment
//[tap release];
cell.textLabel.text = [contentArray objectAtIndex:indexPath.row];
return cell;
}
- (void) handleChecking:(UITapGestureRecognizer *)tapRecognizer {
CGPoint tapLocation = [tapRecognizer locationInView:self.tableView];
NSIndexPath *tappedIndexPath = [self.tableView indexPathForRowAtPoint:tapLocation];
if ([selectedRowsArray containsObject:[contentArray objectAtIndex:tappedIndexPath.row]]) {
[selectedRowsArray removeObject:[contentArray objectAtIndex:tappedIndexPath.row]];
}
else {
[selectedRowsArray addObject:[contentArray objectAtIndex:tappedIndexPath.row]];
}
[self.tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:tappedIndexPath] withRowAnimation: UITableViewRowAnimationFade];
}
In that code i have one doubt. what is selectedRowsArray and what is ContentArray Please explain anyone. Thanks in advance.
The selectedRowsArray is another array maintained beside your contentArray which is used to hold the content for of the cells that are currently selected in the UITableView. The contentArray holds the actual content which is populated the cells.
Make note of the following lines:
if ([selectedRowsArray containsObject:[contentArray objectAtIndex:indexPath.row]])
{
cell.imageView.image = [UIImage imageNamed:#"checked.png"];
}
else
{
cell.imageView.image = [UIImage imageNamed:#"unchecked.png"];
}
The cell contents are checked for their presence in the selectedRowsArray which means that the cell is selected.
The selection and deselection is handled by the handleChecking: method which adds or removes the object from the same index in the contentArray into the selectedRowsArray.
You must have understood by now that cells in a UITableView are reused, so the actual number of UITableViewCells in the memory are most probably less than the number of cells to be shown in the UITableView. Hence the need for a system which can actually determine whether the cell is currently selected so this status can be populated when the cell is rendered again in the view.
Alternative methods to achieve the same involve using Booleans in an array representing the status of each cell, or simply the indexes of each selected cell in an array.
I am having trouble trying to make an image inside a TableView to not to be oversized. I drag and drop the UIImageView in the UITableViewCell and set the height and width visually (I am using Storyboards). But when I ran the app, the image looks oversized. No matter what i do (set constraints, CGRectMake among other methods), the image always looks the same).
This is my tableView cellForRowAtIndexPath method:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellID = #"cell";
TFGResultsTableViewCell *cell= [tableView dequeueReusableCellWithIdentifier:cellID forIndexPath:indexPath];
if(cell == nil) {
cell = [[TFGResultsTableViewCell alloc]
initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:cellID];
}
// Configure the cell...
cell.eventnamelabel.text = [eventnameArray objectAtIndex: [indexPath row]];
cell.userLabel.text = [userArray objectAtIndex: [indexPath row]];
cell.sportnameLabel.text = [sportnameArray objectAtIndex: [indexPath row]];
if([cell.sportnameLabel.text isEqualToString:#"Soccer"]){
// Here I should do something to resize the image!
cell.imageView.image = [UIImage imageNamed:#"icon.png"];
}
return cell;
}
These are screenshots of my current image setup:
Finally i got the solution:
cell.imageView.image = [UIImage imageNamed:#"icon.png"];
should be rewritten like:
cell.eventImage.image = [UIImage imageNamed:#"icon.png"];
In your UITableViewCell you create an IBOutlet to eventImage. But in cellForRowAtIndexPath you doing like this,
cell.imageView.image = [UIImage imageNamed:#"icon.png"];
Above way is wrong. you should do as below.
cell.eventImage.image = [UIImage imageNamed:#"icon.png"];
Why it doesn't show the contents of the cells in a UITableView filtered by a uisearchdisplaycontroller.
In practice when I execute the search in the Searchbar, the cells are decoded correctly (in fact the number of cells sorted by the search is exact) but also configuring them in cellForRowAtIndexPath cell content is not shown (image and text).
In addition, if I click on one of the cells searched, the exact way in prepareForSegue performs the transition to the corresponding viewController.
So the problem is just that it doesn't show text and image in my cell.
Considering that the array configuration (array searchResults) is correct, I show you my method cellForRowAtIndexPath:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *identifier = #"MyCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:identifier];
cell.backgroundView = [[UIImageView alloc] initWithImage:myImage];
if ( cell == nil ) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier];
}
if (tableView == self.searchDisplayController.searchResultsTableView) {
UIImage *profileSnap = myProfImage;
NSString *name = [searchResults objectAtIndex:indexPath.row];
UILabel *cellLabelName = (UILabel *)[cell viewWithTag:1];
cellLabelName.text = name;
UIImageView *cellImage = (UIImageView*)[cell viewWithTag:2];
[cellImage setImage:profileSnap];
}
else{
//here it all works
UIImage *profileSnap = [self.arrProfileSnaps objectAtIndex:indexPath.row];
NSString *name = [self.arrNames objectAtIndex:indexPath.row];
UILabel *cellLabelName = (UILabel *)[cell viewWithTag:1];
cellLabelName.text = name;
UIImageView *cellImage = (UIImageView*)[cell viewWithTag:2];
[cellImage setImage:profileSnap];
}
return cell;
I'm having a problem with my current App. It has one UITableView in the UIViewController. I have one UIButton at the bottom (out of the UITableView). It works in that way:
if ([[NSUserDefaults standardUserDefaults] boolForKey:#"bla"]) {
[[NSUserDefaults standardUserDefaults] setBool:FALSE forKey:#"bla"];
[tableView reloadData];
} else {
[[NSUserDefaults standardUserDefaults] setBool:TRUE forKey:#"tasks2do"];
[tableView reloadData]; }
This worked when I had the cell.textLabel.text Method in this way:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *ident = #"indet";
cell = [tableView dequeueReusableCellWithIdentifier:ident];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:ident] autorelease];
}
if (![[NSUserDefaults standardUserDefaults] boolForKey:#"bla"]) {
cell.textLabel.text = [firstArray objectAtIndex:indexPath.row];
} else {
cell.textLabel.text = [secondArray objectAtIndex:indexPath.row];
}
return cell; }
Now I want to use an UILabel instead of cell.textLabel, because I need it for some reasons (eg. setting the labels frame)
For that I used the following code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *ident = #"indet";
cell = [tableView dequeueReusableCellWithIdentifier:ident];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:ident] autorelease];
}
UILabel *thislabel = [[[UILabel alloc] initWithFrame:CGRectMake(10, 10, 250, 44)] autorelease];
if (![[NSUserDefaults standardUserDefaults] boolForKey:#"bla"]) {
[thislabel setText:[firstArray objectAtIndex:indexPath.row]];
} else {
[thislabel setText:[secondArray objectAtIndex:indexPath.row]];
}
[cell.contentView addSubview:thislabel];
return cell; }
That works fine, until I push the UIButton for switching. It switches, the cell shows the new text but behind the new text is still the old text as you can see here:
http://d.pr/Rqx2
(the firstArray contains the letter L, the secondArray contains the Letter J, it mixes up both up)
Do you have any idea for solving this problem since I tried some stuff (for example using 2 UILabels for the arrays and hide one)? Would be cool. :)
I hope my English is not too bad to understand, my English skills for writing aren't the best, I'm sorry for that.
If you need further information / code just post it, shouldn't be a problem.
I recommend you create a UITableViewCell subclass in which you configure the label (set frame and add it as subview in UITableViewCell's initializer). Add a property for setting the text in the label and write a setter like this for the property:
- (void)setLabelText:(NSString *)newLabelText
{
if ([self.labelText isEqualToString:newLabelText]) return;
[labelText autorelease];
labelText = [newLabelText copy];
self.label.text = labelText;
[self.label setNeedsDisplay]; // or perhaps [self setNeedsDisplay];
}
Edit: by the way, the issue you're dealing with is the caching. You recreate a new label every time a cell comes in view, even if the cell already had a label before. This happens because you initialize an UILabel outside the UITableViewCell initializer (which only should be called once for every cached cell, afterwards it can be retrieved from cache, including all it's subviews).
I have this code, where "lineaRedToday" is an UIImageView:
- (void)viewDidLoad {
[super viewDidLoad];
lineaRedToday = [UIImage imageNamed:#"line4.png"];}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *MyIdentifier = #"MyIdentifier";
MyIdentifier = #"tblCellView";
TableViewCell *cell = (TableViewCell*)[tableView dequeueReusableCellWithIdentifier:MyIdentifier];
if(cell == nil) {
[[NSBundle mainBundle] loadNibNamed:#"TableViewCell" owner:self options:nil];
cell = tblCell;
}
cell.selectionStyle = UITableViewCellSelectionStyleNone;
[[lineDay objectAtIndex:currentTodaylineRed -1] setImage:lineaRedToday];
return cell;
- (IBAction) change{
lineaRedToday = [UIImage imageNamed:#"linea.png"];
[lineDay setImage:lineaRedToday];
[myTableView reloadData];
}
It is a UITableView with 15 custom UITableViewCell and I want to change the image at an UIImageView, this ImageView is "lineDay", lineDay is present in all cells, and I want change its image at all cells, but the IBAction "change" change the UIImageView only in the last cell and not at all....why?
yes it will change the image in last cell because it has the reference of only last cell, if you want to do this then when you are creating cell in cellForRowAtIndexPath check for a BOOL and set image according that BOOL. Also in IBAction change that BOOL value and call reloadData on table view to reload it. As -
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Test";
UITableViewCell *cellView = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cellView == nil)
{
cellView = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
UIImageView *bgImgView = [[UIImageView alloc] initWithFrame:CGRectMake(0.0f, 0.0f, 320.0f, 85.0f)];
[bgImgView setTag:1];
[bgImgView setBackgroundColor:[UIColor clearColor]];
[cellView.contentView addSubview:bgImgView];
[bgImgView release];
}
UIImageView *imgView = (UIImageView*)[cellView viewWithTag:1];
if (buttonPressed)
{
[imgView setImage:[UIImage imageNamed:#"listing_bg"]];
}
else
{
[imgView setImage:[UIImage imageNamed:#"featured_listing_bg"]];
}
return cellView;
}
- (IBAction) change{
buttonPressed = !buttonPressed;
[myTableView reloadData];
}
First, lineaRedToday is an UIImage, not an UIImageView. The first is an image, the second an object in the view hierarchy.
Then, in your code
if(cell == nil) {
[[NSBundle mainBundle] loadNibNamed:#"TableViewCell" owner:self options:nil];
cell = tblCell;
}
you use tblCell. I cannot see what this is. You should assign something from what you were just loading from the nib.
I don't know what lineDay is exactly, but a single view (i.e. UIImageView) can only be present in one cell, not in many. If you change the image (lineaRedToday), you still have to set this new image in your views. There should be something like
cell.yourImageView.image = linaRedToday;
when configuring the cell.