I am working on an iPhone project containing a ton of code. The application receives outside requests and performs actions. However, I cannot figure out exactly where the app begins executing code for a particular event. Is there some functionality in Xcode which would allow me to solve this problem?
Thank you.
Have you tried setting break points in your code? Click on the line numbers column in Xcode on the number to set a break point.
Without knowing more about what these requests are or where they are coming from, its hard to give any advice on what tools Xcode might have, but looking in any project files named <xxx>AppDelegate.m or <xxx>Controller.m would be a good start, placing breakpoints on likely sounding methods.
I figured out that you can use the Instruments Profiler to this end.
Start the profiler
Choose "Time Profiler"
In the bottom left section make sure the following are checked: Show Obj-C only and Hide System Libraries
In the timeline, click on the the point before the event occurred.
Click the left-most icon in "inspection range" (located on the top-bar immediately to the left of clock)
In the timeline, click on the point after the event completed. (optional)
Click the right-most icon in "inspection range"
Inspect the Call Tree.
Related
I have been working on my project when suddenly I have not compiled anymore, it stays waiting in Compile swift source files ... I cleaned the project, the folder, deleted the app and nothing. Is there any way to know what is happening?
Is there any way to know what is happening?
Yes. Go into the Report Navigator which is the one selected by the little speech bubble at the top right of the navigator pane. It will give you a list of all the actions you have performed like builds and tests and runs. The current build will be at the top of the pane. Click on it.
In the main editor you will see some buttons at the top and maybe some messages. Click the All Messages button and it will show you a tree view of the current build. The bottom line will be what the build system is doing now. If it is not changing (i.e. new lines appearing) the build is stuck.
Almost certainly the bottom line will be something like Compile SomeFile.swift. Assuming it is, you can now triage the problem. The Swift compiler usually gets stuck on inferring types for complicated expressions. The way to triage this is to comment out the entire file and then add lines back until the problem reappears. Make sure that you always add enough back so that the file compiles without error.
Obviously, the last line you added back will be the one causing the problem. Usually it's an expression that concatenates strings together with non strings that causes the problem.
The problem is in dictionary [String:Any] when I change the dictionary to [String:String] the problem is resolved . Is very strange..
How to know what are the lines of code covered in the java class for a particular point of execution in eclipse. For example,if button click event is fired then how to know what are the lines of code is being executed during this event. Any plugins in eclipse or any free software for this to track the code ?
Go to the following page, it will instruct you through the process. The only thing you need to do is prepare a j-unit test for your code (for the method that gets called when pressing the button).
http://crunchify.com/what-is-the-best-code-coverage-plugin-you-should-use-in-eclipse-ide/
After mild frustration with the difficulty to make top-level "plain old folders" within Eclipse for visual-organization purposes, I discovered that the thing I'm after is called a "working set". Hooray! But they don't seem to be rename-able, by any of the apparent avenues (right-clicking on it or using the Configure Working Sets window).
Is that just the way things are, since no one should be so lazy as to refuse making a new working set with the right name and transferring everything over? Or am I missing something obvious?
I also have a more minor question whose answer I already think I know. Can I tell a specific working set not to change its icon to have the "red X" when one of its children has an error? Nothing in the preferences under Debugging suggests to me the ability to turn off the automatic icon-changing. It's a useful feature, but I have a few simple practice projects with very basic errors, and I don't need the visual reminder to "fix" them, especially if they're in my "Practice" working set, whose icon I'd prefer not to change.
To rename a Working Set, you need to get to the dialogue of selecting a Working Set (click on the white down arrow at the top right of the package explorer > Configure Working Sets..), focus on your Working Set and click the "Edit" button. There, you can change the Working Set's name, as well as what's actually included in the Working Set.
There is no way (that I know of) to change the icon display to avoid showing the errors marker.
I am developing using the PyDev plugin in Eclipse. My program uses several classes in several files. I usually run the program using the green "play" icon or using Control+F11. The only problem is that it will run the file, which is currently in "focus". Usually this is not the one containing the starting point of my application. As I run my program something like 200 times a day, this means that I need 200 extra click on the mouse and often forget about this.
Is there any way of setting the default file to launch?
Yes, change the launching to rerun the last launched, so Ctrl+F11 will launch the last one -- and use F9 to launch the one with focus -- See instructions and details at: http://pydev.org/manual_101_run.html
For me, the shortcut is Ctrl+Shift+F9. I don't think I've changed any keybindings, so its strange that it would be different from the official documentation.
Go to Run->Run History, and select the run that is your 'main' run. Now you should be able to use Ctrl-Shift+F9 from any other file to rerun your main. If it isn't Ctrl+Shift+F9 for you, look on the console window that should be at the bottom of your screen showing the stdout after every run. There is an icon on the top of it that has the green start arrow with a yellow arrow underneath it pointing to the right. That is the command to relaunch with the same configuration. If you hover over that, it should tell you the keyboard shortcut you need.
I'm still relatively new to XCode. I'm trying to build an iPhone application and after my application didFinishLaunchingWithOptions method runs but not inside of any code I can find I get this error:
[58036:207] *** -[_PFArray release]: message sent to deallocated instance 0x17cd2fe0
I have no idea what that means apart from the fact that some array somewhere is being released when it's already released?
The real problem, is that I have no clue how to use the information provided there to find where the error is. There is no line of code to look in, no variable name, etc.
How do I use this information to find what I'm looking for?
try enabling zombies, then xcode puts a breakpoint automatically to the line where this error occurs. Google nszombieenabled for more information
Edit: Well, I don't have much thing to do so here your guide,
Open instruments. It is an application and you can find it in "~/Developer/applications/instruments" (in a default installation path). Instruments will be your right hand so master it well.
In the opening screen, you will see a bunch of templates. Open the one named "Zombies". Note: You will often use the template named "Leaks". It shows all the memory leaks you forget to release.
From "choose target" (top left corner), select "choose target", and again select "choose target". From here, browse the project directory, and choose "build/Debug-iphonesimulator/executableName". Here I assume that you have built your project in debug profile with nszombieenabled to true. If not, build it so and reply 3.
Press record button (top left corner). The simulator will appear and your app will start. Then reproduce the error you have encountered.
Instruments will interrupt the app showing a message bubble. Do not close the bubble. From the bar in the middle of the window, select "objects list" instead of "statistics". Now, all the objects allocated up to this point lies in a list sorted by their memory addresses. Here scroll down to the memory address written inside the bubble. You can type the initial letters for fast scroll. Then double click the line you found. This brings you to the code where the object is allocated IF THE CODE IS YOURS. If it is not, then ios allocated the object. But do not worry, and double click the lines below and above to see if they are allocated by you. This should give you a hint where may be the problem is since these lines triggered ios to allocate the object (possibly).
This is all I can say. I hope you can find what causes this error.