I've been programming for a while, but just recently decided to start developing for Mac OS X. I feel like I've come to grips with the basics of Objective-C and Cocoa development over the past week. I'm planning on making graphics apps, and as such am currently in the process of learning how to control Quartz compositions through a Cocoa app. I went through the tutorial that apple offers (with the Mac Engravings composition), and was able to create that just fine. In order to make sure that I truly understood what I learned, I decided to create my own composition and link it to a slightly more complicated Cocoa application.
Essentially, I have a composition that loads a movie or image through a Movie Loader patch, at which point it applies various filters to the frames before outputting it. In my Cocoa app, I've written code (or rather copied and pasted from other apple examples) that lets a user pick a file using an NSOpenPanel object. The filepath of the file they pick gets placed in a text-box that I placed in the app's window using Interface Builder. I binded the value of said text-box to the "Movie_Location" key in my composition, which is a published input in the Movie Loader patch that I'm using. However, no matter what I do, movies and images aren't loaded into this composition no matter what I try. The only thing that gets displayed is the default image that I have saved in that input from Quartz Composer (or nothing if I leave it blank before publishing).
I've added a Clear Color patch to the composition and binded that to a colorwell in my UI, and that successfully changes the color in my display, so I know that the composition and my Cocoa app are communicating. I've spent numerous hours at this point trying to figure out what's going on, and I've just about given up. Does the Movie Loader have any weird behaviors that I'm not aware of, or is there something obvious that I seem to be missing? I'd really appreciate any help or advice from anybody.
Thanks for reading through this...
Best,
Sami
There are two things I can think of as reasons why it is doing this:
The file path isn't formatted incorrectly. Try checking backslashes, colons, etc.
The box isn't updating the value. Try literally clicking in the text field and hitting enter.
That's all I can think of without seeing your quartz composition and/or code.
EDIT:
Check the other continuous box, in the general properties.
I figured this out yesterday. spudwaffle's second idea is what was going on. If I were to type a filepath in and hit enter, it would work just fine. I got this to work properly by just removing the bind and instead using the setValue:keyInPath: function that a patch controller offers. That said, is there some way to force a text-box to update? I remember seeing a "continuously update" or something like that button within the bind sub-menu in the inspector, but my code didn't work with that checked either.
Thanks to those of you that tried to help me! I really appreciate it.
Best,
Sami
Related
Ok so this question is actually in two parts.
I coded a video filter for VLC and I would like to add a control to the Video Effects panel on the OS X UI. So far I've been able to link my plugin the the UI by hijacking one of the existing controls, but this isn't ideal.
Now, if I open up the Xcode project (I'm running Xcode 6.3.1) and try to open the VideoEffect.xib file, I get the following error:
I tried to google this but it sounds like the only alternative would be to play archaeologist and dig up an old copy of Xcode 3. Is there any other way to be able to open this file and edit it somehow? I tried to look at the XML code but if I started to change that I'd do more damage than good.
The second thing I'd like to do is sending back values from the effect module to the UI. At the moment (by hijacking one of the existing sliders), all I can do is read a value from the panel with
config_ChainParse(p_filter, FILTER_PREFIX, ppsz_filter_options, p_filter->p_cfg);
p_filter->p_sys->i_factor = var_CreateGetIntegerCommand(p_filter, FILTER_PREFIX "factor");
and then, inside the callback function:
p_sys->i_factor = VLC_CLIP( newval.i_int, 0, 255 );
However, I haven't been able to write back the value. I'd like the filter to set p_sys->i_factor to a random value at start. This works (using var_SetInteger()), but it isn't reflected in the position of the slider in the Video Effect panel. I suspect I need to hack a bit deeper for that. Any ideas?
Regarding your first question with the xib-file. Consider downloading and using our forthcoming 3.0 code from git://git.videolan.org/vlc.git - it allows editing of said file without Xcode 3.
Regarding your second question, why would you want your video filter to interfere with the UI? This is not how the architecture of VLC works and there is no correct way to do it at this point. You would need to edit the core to do another global variable callback to ask the UI to reload the presented filter configuration.
Perhaps, if you give details about what your filter does and what you want to achieve, we find a more supported way :)
Currently, I have an RSS Feed Reader in a UITableView within a Navigation Control. I would like to click on the links and Open up a formatted page (containing all of the information from the website formatted for the iOS screen). I'm not sure if I should do this using the RSS data and a UITextView? I'm currently attempting to use UITextView in hopes that I can separate the information (title, author, body) without anything looking promising. I want to be able to move around the data and format it to my liking in the actual application itself. I read around and noted that you can include HTML and custom CSS. Would this be the way to go? I'm not quite sure how to tackle this. I want the page that opens up to be entirely scrollable (Like the IGN application or Slashgear application). Many apps for websites utilize this (and I am a bit new to this). How do they go about this? I also want to note, at some point I will like to cache the data so it may load what is already loaded without being connected to the internet. Does anyone have any ideas?
Edit:
Ok, I believe I found the correct path to go down from playing around and a lot of googling (nothing directly says what a decent way of doing this is). My particular way as of now is the route of a UIScrollView in general. Now the part I don't understand is how to divide up the long text into 'pages' for scrolling (and I am using the paging feature. This situation has led me into this question: How To Separate Strings For UIScrollView/UITextView based on the size of the frame
Ok, I believe I found the correct path to go down from playing around and a lot of googling (nothing directly says what a decent way of doing this is). My particular way as of now is the route of a UIScrollView in general. Now the part I don't understand is how to divide up the long text into 'pages' for scrolling (and I am using the paging feature. This situation has led me into this question: How To Separate Strings For UIScrollView/UITextView based on the size of the frame
I'm getting my hands dirty with a bit of ObjC by trying to write something Dock-like, with a little less visual bells and whistles. It's going pretty well. However I've stumbled over a problem which I can't quiet solve:
Retrieving an app's icon via NSRunningApplication is easy. However, some apps don't use their icon as DockTile, they use a custom view because their DockTiles are dynamic (f.e. most torrent apps display their current up/down speeds in the dock).
Is there any way to get this DockTile and display it in my own app?
Thanks
No, there is not. The methods which set a custom dock tile end up communicating the contents of the view directly to the Dock; it is not made available to other processes.
For what it's worth, writing a replacement for the Dock is going to be a kind of hopeless task -- Apple's Dock.app uses numerous private, undocumented APIs to interact with the WindowServer, some of which simply cannot be used by any process which is not the Dock.
I need to build an app such as "Messages" in iPhone, but easier (don't need to send messages to server, only in datebase). I was faced with some questions.
http://www.ibm.com/developerworks/library/x-ioschat/index.html
In this tutorial messages look like TableView, how can I do them such as in iPhone standard messanger (comics speach). And how can I implement bar with camera button, text box and send button (what class is responsible for this)?
You are in luck good sir, there is already a class that can fix you up with this and avoid all the work, it's called AcaniChat (screenshot provided). Or you can even see at Sam Soffle's SSMessagesViewController, he is a well known iOS developer who built this class.
It will definitely help you, if you want to mimic that behavior.
I am developing an iPhone application where i want to display three image in each row on scroll view where i need to click action on each image like Photo album in iPhone. I am not getting any sample code.
Hoping for help
subodh
There's plenty of sample code out there, I found this after only basic googling. You want to search for "UIImageView Iphone". It's also worth mentioning that Apple's very own Developer Center is extremely well written, and will teach you everything you need to know about iPhone programming.
Generally it is frowned down upon to say to look more or read documentation, but you really haven't looked at all. Especially because of Apple's own resource that tells you how to do almost anything, especially something like this. It's not something you can pick up and bits and pieces of and expect to be successful with, it really should be learned starting from the beginning and moving forward. This is especially true if you've never programmed before or are unfamiliar with C/Objective-C.
Three20 has a photo browser that is open source and works similarly to the iPhone's photo browser with some nice code examples. The images come from an image source object that can relate them to images in your apps bundle or images on the web. Looks like its Google group is here. I think that to use images in your bundle you use a URL formed like: bundle://image-name.png and not the typical use of the main bundle to get a path to resource.