I have a Titanium app where I am using the same ImageView for alot of different images. I am changing the image in the image view by setting it's image property.
The problem is some of the images are not showing at their full size sometimes, it is kinda random, but sometimes they show full size sometimes not.
I have width and height set to "auto" on the image view.
Anyone come across this issue.
A potentially more reliable way would be too dynamically resize the image before handing it off to the ImageView by using Titanium.Blob.imageAsReized.
Try to integrate this in your code, first you have to load the image as a blob though.
// Get the blob of your image first, then call this method
imageView.image = imageBlob.imageAsResized(newWidth, newHeight);
Related
I have a situation were I'm trying to draw an image into a display's CGContext retrieved using CGDisplayGetDrawingContext. Despite having the image at the correct high resolution, using CGContextDrawImage to draw the image onto the context results in a pixilated image. I've also tried scaling down the image in a bitmap context (using CGBitmapContextCreate) then drawing that one onto the display's context, however that also results in a pixilated image (I thought it may retain the DIP, was a long shot). Any idea how to fix this?.
My question is, why does the iPad preview use a different image than the storyboard for wRegular hAny?
I'm trying to set up a universal app with a menu that will use larger buttons for iPad. In the asset catalog, I've specified the standard image size for wAny x hAny, and loaded a larger image for wRegular x hAny.
The story board looks fine for all size classes, with the wRegular x hAny using the iPad image, and everything else using the iPhone image. But the previews all use the iPhone image, including the iPad preview, despite the storyboards showing the correct images. In the screen shots below, the story board is shown to the left, preview to the right.
Can someone tell me what I'm doing wrong here? I'm trying to avoid using explicit image sizes for each class - is that what I should be doing?
Any help would be greatly appreciated. I've read everything I can on using different image sizes, and still cannot figure this out.
enter code here
You can't have a different images by size class for the same button in Interface Builder. It looks to me like you set the image of the button to be the iPad one first in Regular/Any, then set the iPhone one afterward in Any/Any which changed what you did in Regular/Any.
In this image, see how the Font has a + symbol to the left of it, but Image doesn't? That's for specifying the value per size class. Since Image doesn't have that, it's not a value saved for the specific size class.
I am fairly new in iOS programming and I am creating my first app.
I have been trying to use the following code to change the navigation bar background image (this is using the new iOS 5 method):
[self.navigationController.navigationBar setBackgroundImage:[UIImage imageNamed:#"gradientBackgroundPlain.png"] forBarMetrics: UIBarMetricsDefault];
It works fine, but my image is 640 x 88 and it looks too big for the bar. It's like the system doesn't want to scale it, or do I need to do it manually? If I scale the image and create a smaller one it looks pixelated in the retina display.
Any thoughts on this?
Any help or response will be appreciated.
Thanks,
Jorge.-
Your image gradientBackgroundPlain.png should be 320x44, and create a second image named gradientBackgroundPlain#2x.png with a size of 640x88. Include the #2x image in your bundle, but continue to specify gradientBackgroundPlain.png for the name of the image. The platform automatically chooses the correct size image for use depending on whether there is a retina display present or not.
I need to take some images from the iPhone / iPad photo library from within my app and store them in a Core Data entity, and display them as small thumbnail images (48x48 pixels) in a UITableViewCell, and about 80x80 pixels in a detail UIView. I've followed the Recipes sample app, where they use UIImageJPEGRepresentation(value, 0.1) to convert to NSData and store the bytes inside Core Data, and it doesn't end up taking much space, which is good. But when retrieve the data, using UIImage *uiImage = [[UIImage alloc] initWithData:value]; and display it as a thumbnail image with "Aspect Fit", it looks terrible and grainy. I tried changing the image quality variable in the JPEG compression, but even setting it to 0.9 doesn't help.
Is that normal? Is there a better way to compress the image that doesn't cause so much grainee-ness? Since I just want to show a small thumbnail, and then a slightly bigger thumbnail, I feel Core Data would be great for storing this, since it should (theoretically) also support iCloud. But if it's going to look terrible, then I'll have to reconsider.
Two things, are you resizing the image to the right size? Have you tried UIImagePNGRepresentation()? That should compress it without losing quality.
If UIImagePNGRepresentation (which is lossless) is giving you bad images, then the problem is in your image resizing code. Core Data is just giving you what you back what you put in, so if you get bad images out, it's because you put bad images in.
Is one of your iPhone/iPad retina and the other isn't? If so, perhaps the problem is that you don't really want 48x48 pixel images, you want 48x48 point (which means you'll need 2x images 96x96 for retina quality display).
How to save UIWebView Content into photo Library
-(IBAction)save:(id)sender{
UIImage* image = nil;
UIGraphicsBeginImageContext(webView.frame.size);
{
image = UIGraphicsGetImageFromCurrentImageContext();
}
UIGraphicsEndImageContext();
if (image != nil) {
UIImageWriteToSavedPhotosAlbum(image,self, nil, nil);
}
}
This code is saving empty page.
I've released an app (Web2Pic) doing that, and please trust me that UIGraphicsBeginImageContext(webView.frame.size);
can do nothing except getting a small image from the visible area in our UIWebView ;-(
The right way is a bit complex but it just works:
1.Use JavaScript in our UIWebView to get these float values:
//Whole page size in HTML coordinate
document.body.scrollWidth
document.body.scrollHeight
//UIWebView visible size in HTML coordinate
window.innerWidth
window.innerHeight
2.Now we can 'cut' the whole page into dozens of UIWebView-sized small pieces. Then we can capture every small pieces individually and save them into our Cache. I implemented this by calculating page-offsets and use UIGraphicsBeginImageContext(webView.frame.size); to get a array of images. In addition, you should cache the image array into the file system, or the app will eventually crash!
3.When we finally got all the small pieces, we can start a full-resolution context: UIGraphicsBeginImageContext(CGSizeMake(document.body.scrollWidth,document.body.scrollHeight));
4.Render every small images into the big context based on the coordinates. And be careful to the corners, the last image in every line/row may not be a full image.
5.There is still one step left: saving the big image. Do not save it into the PhotoAlbum, because iOS will automatically cut down the resolution of images in the album. Instead, we can save it into the file system and enable the app's iTunes File Share support, or even write a simple in-app photo manager.
Hope these can help ;-)
Yichao Peak Ji