Proper Way for Create Dynamic UIButton in ScrollView? - iphone

Question

I am new to iOS Development.
I have a navigation based Application, In my application I created dynamic buttons by using a for loop.
I have two UITextFields (row and column) in FirstViewController. When user enters a value of row and column then click on OK Button the values of row and column passes to anOtherViewController. In anOtherViewController I have to put a logic to create All Buttons based on row and column value.
MyLogical Code:
for (int i = 1 ; i <= rows; i++)
{
for (int j = 1 ; j <= columns ; j++)
{
NSString *btnTitle = [NSString stringWithFormat:#"%d",buttonCount];
self.btnCount = [UIButton buttonWithType:UIButtonTypeRoundedRect];
self.btnCount.tag = [btnTitle intValue];
[self.btnCount setTitle: btnTitle forState: UIControlStateNormal];
[self.btnCount addTarget:self action:#selector(btnCountPressed:) forControlEvents:UIControlEventTouchUpInside];
self.btnCount.frame = CGRectMake(162+changedX, 60+changedY, 43, 43);
[self.scrollView addSubview:self.btnCount];
[self.listOfbtnCount addObject:btnTitle];
changedY = changedY + 50;
buttonCount = buttonCount + 1;
}
changedX = changedX + 55;
if (i == rows)
widthScView = changedX;
if (heightScView == 0)
heightScView = changedY;
changedY = 5;
}
My ScreenShot:
It works fine, but my problem is that if I enter values of row and column more then 40 (about) then my app takes more time to create the dynamic button. The issue is only related to the time required to create the button.
Is there any way to create a button faster? and I also need to know is if my code is bad for memory management? please help me on this issues.
For Information : I Have no errors generated, I have issue of only time consuming process of creation of Buttons.
Thank in Advance.

Answer 1

You should use UICollectionView for this.
UICollectionView works a lot like UITableView in that it'll manage the cells that are displayed on screen, including scrolling, and it'll ask its data source for new cells as it needs them. You can also recycle cells, so you'll only need to create about enough to display, plus a few extra. This should really improve performance, especially when scrolling.
Apple has some sample code using UICollectionView here, and watching Introducing Collection Views in the 2012 WWDC Videos will get you off to a good start.
my problem is that If i enter values of row and column more then 40
Forty rows of forty columns would give you 1600 buttons, most of which don't need to exist most of the time. By managing which cells are needed on screen for you, UICollectionView will reduce that to around eighty (judging by your screen shot). You should see much, much better performance this way.
UICollectionView will also simplify positioning the buttons once you've configured the collection view (which you can do in code or in Interface Builder), you won't need any code of your own for calculating the positions of the buttons.

Answer 2

just implement you logic here with your requirement..
int imageIndex = 0;
int yOffset = 4;//set offset which you want...
while (imageIndex < rows)
{
int yPos = 7 + yOffset * 30; // set distance in height between two raws
for(int i = 0; i < columns; ++i)
{
CGRect rect = CGRectMake((0 + i * 80), yPos, 80, 31);**// here set frame of every button with different x and y postion// here width of button is 80 and height is 31**
if (imageIndex < rows) {
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
button.frame = rect;
button.tag = imageIndex;
[button addTarget:self
action:#selector(btnTemp_Clicked:)
forControlEvents:UIControlEventTouchDown];
[button setTitle:[NSString stringWithFormat:#"%d",imageIndex] forState:UIControlStateNormal];
[button.titleLabel setFont:[UIFont fontWithName:#"Helvetica-Bold" size:12]];
// [button.titleLabel setTextColor:[UIColor blueColor]];
[button setTitleColor:[UIColor colorWithPatternImage:[UIImage imageNamed:#"circle03.jpg"]] forState:UIControlStateNormal ];
[button setTitleColor:[UIColor redColor] forState:UIControlStateHighlighted ];
[button setNeedsDisplay];
[yourScrollView addSubview:button];
}
++imageIndex;
}
++yOffset;
}
See the screen which i got output..

Answer 3

Try this method
-(void)ScrollViewSetting {
scrollview.scrollEnabled=YES;
scrollview.userInteractionEnabled=YES;
TotalStyleX=25;
TotalStyleY=18;
int count=0;
int px=0;
int py=0;
for (int i=1; i<=TotalStyleX; i++) {
px=0;
for (int j=1; j<=TotalStyleY; j++) {
count++;
UIButton *btn1=[[UIButton alloc] init];
btn1.tag = count;
btn1.frame=CGRectMake(px+10, py+10, 300, 380); //you can set your height and width your x and y position
[scrollview addSubview:btn1];
px=px+320;
}
py=py+400;
}
[scrollview setContentSize:CGSizeMake(px, py)];
}