In learning Objective-C and how to create ios apps, I'm following some tutorials using Xcode(5.1.1).
In this one, I have a 64x64 pixel Image view on the left hand side with a text field immediately to it's right stretching to the right hand edge of screen and a text view below it. In the simulator, when I add a photo, the photo is correctly sized but the text field is significantly enlarged and the text view has disappeared.
I figure it's an error on my part but I can't see where, so I need some guidance.
I tried, but Stackoverflow won't let me post images unless I have a reputation 10 or greater.
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My problem is three-fold. I'm going to try to explain as detailed as I can, because I've asked this question before and haven't gotten any clear answers.
What I'm Trying to Do:
I have diagonally shaped images, that I'm trying to make clickable, so I separated them out of the background image. They were originally one image, but I've cut out several pieces of the image and I want to align them identically to how they were in the original image. This might not the best method for what I am trying to achieve, and if there is a better way to make non-square areas of an image clickable, that would solve all of these problems. If not, here is my problem. The problem is, as soon as I align them in XML, I boot them up on an Android emulator or my phone, and they are aligned differently on both, differently than the preview and from each other.
Below is my example, and I'll try to explain what I mean.
The black and white grid is my background. The brown, red, and yellow lines are separate images. I don't want to just combine them with the background, because I need those lines to be clickable. I'd set a button behind them, but they are diagonally shaped and I need the entire shape to be clickable. However, they have to be EXACTLY where they are in the background, aligned specifically as they are to the background. The problem is, as soon as I load it on another device, it scales, and everything misaligns.
It also misaligns depending the device, so I presume it's because it's scaling the different parts differently.
I need a way to align it the way I want it, and have each image scale together.
How I've Been Trying This So Far:
Initially, I tried just using XML. And herein was my first problem. My background image is 1920x1080. It loads on the emulator without a problem. However, if I try to load it on my phone, I get the following error:
OpenGLRenderer: Bitmap too large to be uploaded into a texture (5760x3240, max=4096x4096)
So that leads to my first question. Why is my 1920x1080 trying to load as 5760x3240?!
I bypassed this, by using Picasso to scale the image to 1920x1080. As a sidenote, in addition to programmatically loading the image, I also am removing the title bar. Here is my OnCreate:
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main_layout);
Picasso.with(this).load(R.drawable.backgroundimage).resize(1920,1080).into((ImageView)findViewById(R.id.background));
On the XML side, I've tried all sorts of different things. Relative layouts, linear layouts, frame layouts...None seem to scale the separate imageviews the same.
Which leads to my second question.
How do I scale two differently sized imageviews together, so that they maintain their alignment on different sized devices?
My second imageview is 198x547(this would be the equivalent of one of the squiggly lines in the example images) and even setting that in Picasso does not maintain my alignment. In fact, that doesn't seem to work at all, since I have to scale it differently to even match the alignment I have in the original image.
Summary Questions
I need a diagonally shaped portion of an image to be clickable. Is cutting the shape out as a separate image the appropriate method for doing so? If not, how do I make such a specific, non-square area of an image clickable?
I need specific alignments to scale together. Why aren't they?
Why does my png file upscale itself?
Thanks to Apple's PictureSwiper sample code and the very nice NSPageController tutorial from juniperi here on stackoverflow, it's pretty easy to get tantalizing close to image viewing capabilities in Preview. Specifically I want to replicate the ability to swipe forwards/backwards between images/pages, use pinch-to-zoom resize the images, gesture to rotate the images/pages, and support two-page mode.
But there are some hurdles that make me wonder if NSPageController is the right approach or if it is too limiting and a custom view controller is needed.
1) Images of varying sizes are simply displayed stacked and if the top/upper layer image is smaller, the underlying image(s) show through. Using the same images in preview, they hide the larger "underlying" images/pages and fade the underlying image in/out with the swipe transition. I could hide underlying images by linking the page controller to the view rather than the image cell (like PictureSwiper), but that causes the entire view to scale on pinch to zoom and overall looks clunky.
2) Is it possible to use NSPageController with more than one image cell, e.g. two-page mode?
3) Is page/image rotation possible with NSPageController?
4) Is it possible to lock the zoom level for all the images, so they are uniformly displayed as navigated?
My apologies if this too general of a question, but the gist is whether NSPageController too limited and problematic to extend which would necessitate building a custom controller from scratch.
Thanks.
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 have a very simple Mac Application; the best way to think of it is a master/detail view. Once an item is chosen on the left-hand side, information appears on the right pane, along with an image (can be various sizes/formats/resolutions due to the source). The user can very quickly select items on the left, and while the detail text on the right-hand pane appears quickly, we notice an immediate lag or plain failure to display the image on the right. Even the largest of images is a few MB, and typically less than 1024x1024 pixels. If the user moves slowly, everything is kosher...but if you go quick, it will hiccup...lag behind a few selections, or not display at all.
I've attempted solutions using nsviews' setNeedsDisplay, and alternatively using Core Animation layers, but nothing seems to do the trick. Is there a guide or set of tutorials on performant image display routines?
Targeting 10.6+
I am creating a simple photo filter app for OS X and I am displaying a photo on an NSImageView (actually two photos on top of each other with two NSImageViews, but the question still applies for a single view too). Everything works super, but when I try to resize the window that contains the NSImageViews, the window (which also resizes the NSImageViews) resizes very slowly, at about less than 1fps, creating a negative impact on the user experience. I want resizing windows to be as smooth as possible. When I disable resizing the image views, the window resizes smoothly, so the cause of the slowdown is those NSImageViews.
I'm loading 20-megapixel images from my DSLR. When I scale them down to a reasonable size for screen (e.g. 1024x768), they scale smoothly, so the problem is the way NSImageView renders the images. It (I assume as the result of this behavior) tries to re-render 20MP image every time it needs to redraw it into whatever the target frame of the view is.
How can I make NSImageView rescale more smoothly? Should I feed it with a scaled-down version of my images? I don't want to do that as it's a photo editing app that also targets retina display screens and the viewport would actually be quite large. I can do it, but it's my final option. Other than scaling down, how can I make NSImageView resize faster?
I believe part of the solution your are looking for is in NSImage's representations. You can add many representations to an image with addRepresentation: I believe there is some intelligent selection done when drawing. In your case, I think you would need to add both representations (the scaled-down and the full resolution bitmap) to NSImage. I strongly suspect drawRect: should pick the low resolution version. I would make sure "scale up or down" is selected in NSImageView, because the default is scale down only, which may force your full resolution image to be used most of the time. There are some discussion in Apple's documentation regarding "matching" under "Setting the Image Representation Selection Criteria" in NSImage, although at first sight this may not be sufficient.
Then, whenever you need to do something with the full image, you would request the full resolution image by going through the representations ([NSImage representations] returns an array of NSImageRep).