Change UIImageView image to another?

[xcoderx]

Hey guys, im very new to the forum. But i decided id ask you all super smart coders out there a simple question. I have 2 pages. ON the first page i simply have 1 button. The second page has a BLANK/EMPTY UIImageView. When the button is pressed, i want an image to be on the second view when that view comes up. Could anybody please help me with this? Thanks a lot!!!

[MattW]

Originally Posted by xcoderx

Hey guys, im very new to the forum. But i decided id ask you all super smart coders out there a simple question. I have 2 pages. ON the first page i simply have 1 button. The second page has a BLANK/EMPTY UIImageView. When the button is pressed, i want an image to be on the second view when that view comes up. Could anybody please help me with this? Thanks a lot!!!

Where is the image that appears on the second view? Is it in your bundle? Is it a local file? Is it off the web?

[daltonclaybrook]

Originally Posted by xcoderx

Hey guys, im very new to the forum. But i decided id ask you all super smart coders out there a simple question. I have 2 pages. ON the first page i simply have 1 button. The second page has a BLANK/EMPTY UIImageView. When the button is pressed, i want an image to be on the second view when that view comes up. Could anybody please help me with this? Thanks a lot!!!

In addition to MattW's question, what do you mean by "page"? Do you mean two pages in a UITabBar, or in a UIScrollView, or do you mean something else?

[xcoderx]

Originally Posted by daltonclaybrook

In addition to MattW's question, what do you mean by "page"? Do you mean two pages in a UITabBar, or in a UIScrollView, or do you mean something else?

I mean like two different view controllers and i switch between them with a button. And im not sure how to answer MattW's question i just threw an Image View onto my .xib file. Thanks for the help btw!

[xcoderx]

Originally Posted by MattW

Where is the image that appears on the second view? Is it in your bundle? Is it a local file? Is it off the web?

you know... im a noob at programming so ill just say that i dragged and dropped my UIImageView onto the .xib file.

[Objective Zero]

He means, where are you getting the images from?

1. You dragged and dropped a image into your project
2. You are downloading it off the internet
3. You are getting it from a local source (not likely)

Which number?

[xcoderx]

Originally Posted by Objective Zero

He means, where are you getting the images from?

1. You dragged and dropped a image into your project
2. You are downloading it off the internet
3. You are getting it from a local source (not likely)

Which number?

Oh i understand. I did Number 1!! Thanks for the clarification!

[Aibo]

Have a global boolean variable that keeps track whether the button was pressed. If it was, set it to YES.

In the 2nd view controller implementation file check the value of this variable, and display the image if it is YES.

[Domele]

No global variables are bad. Create a BOOL property in the 2nd view controller and name it something like displayImage. In your view will appear method, check the BOOL and act accordingly. Now when you go to push your 2nd view controller, set that property.

[xcoderx]

Originally Posted by Domele

No global variables are bad. Create a BOOL property in the 2nd view controller and name it something like displayImage. In your view will appear method, check the BOOL and act accordingly. Now when you go to push your 2nd view controller, set that property.

ok, i have tried this BOOL method and many others to try to get this to work, but it wont? IS there another way to do it?

[Domele]

Post code, it has to work.

[xcoderx]

Originally Posted by Domele

No global variables are bad. Create a BOOL property in the 2nd view controller and name it something like displayImage. In your view will appear method, check the BOOL and act accordingly. Now when you go to push your 2nd view controller, set that property.

ok, here is my code:

THis is for the button that i want to set the image in the second controller:

- (IBAction)outlet1 {
cart.displayImage = YES;
}


This is the viewDidLoad for the second viewController


- (void)viewDidLoad; {
[super viewDidLoad];
if (displayImage == YES) {
imageView.image = [UIImage imageNamed:@"paddle1.png"];
}
}

I set and check the bool then set the image but i dont know why it wont work? Thanks

[MattW]

Here's the flow:

1) User hits button
2) VC1 creates VC2, and sets the BOOL value in VC2
3) VC1 excuses itself, and adds VC2 to the subview or pushes it.
4) VC2, in its viewWillAppear() checks the state of its BOOL and does the appropriate thing with the image.

And that's it.

Things to note:

1) The BOOL needs to be in the VC that will display the image (VC2)
2) The button press IBAction function will be in VC1.
3) You have to create VC2 before you can set the BOOL variable.

[xcoderx]

Originally Posted by MattW

Here's the flow:

1) User hits button
2) VC1 creates VC2, and sets the BOOL value in VC2
3) VC1 excuses itself, and adds VC2 to the subview or pushes it.
4) VC2, in its viewWillAppear() checks the state of its BOOL and does the appropriate thing with the image.

And that's it.

Things to note:

1) The BOOL needs to be in the VC that will display the image (VC2)
2) The button press IBAction function will be in VC1.
3) You have to create VC2 before you can set the BOOL variable.

Ok i think i got it, but what do you mean by create VC2 before i set the variable? P.S. i checked out your apps on the store and they are some pretty sweet looking apps, and i bought the highlighter one!! Thanks again!

[MattW]

Originally Posted by xcoderx

Ok i think i got it, but what do you mean by create VC2 before i set the variable? P.S. i checked out your apps on the store and they are some pretty sweet looking apps, and i bought the highlighter one!! Thanks again!

LOL. Flattery will get you everywhere.

You need to create (alloc and init) an instance of VC2 (view controller 2.... whatever you've called it) as you would before you add it to the sub view or push it, otherwise there won't be memory allocated to store its data (basically, it won't exist).

[xcoderx]

Originally Posted by MattW

LOL. Flattery will get you everywhere.

You need to create (alloc and init) an instance of VC2 (view controller 2.... whatever you've called it) as you would before you add it to the sub view or push it, otherwise there won't be memory allocated to store its data (basically, it won't exist).

lol
ok i got it!
I tried this code and it will not work? My nibs are good to go and the code seems flawless. Is there a reason the image isnt displaying? Could it be some thing to do with how i switch back and forth through the pages? Thanks again! Oh and MattW i have been coding for about 1 and a half years and im 16 years old and i was wondering is this a good career to get into? Do you make a lot or a pretty good amount of money? Thanks again!

[xcoderx]

Originally Posted by MattW

LOL. Flattery will get you everywhere.

You need to create (alloc and init) an instance of VC2 (view controller 2.... whatever you've called it) as you would before you add it to the sub view or push it, otherwise there won't be memory allocated to store its data (basically, it won't exist).

OH I GOT IT!!!! i was messing things up with my ivars. I just learned that i had to init the cart object in the init method!! THANKS FOR ALL THE HELP!!!!

[MattW]

Good! Well done for figuring it out - that's the way to learn.