Show call stack / executed methods without setting breakpoints? - android-studio

Is it possible to record all methods called by my Android app without setting any breakpoint? E.g. if I have no clue where to start, but just want to know which methods are called in my app (and the libraries it uses) during the action I perform by using my app. How could I do that?

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onCreate method in Android studio

I have started learning Android development recently and have some doubts. " What invokes onCreate method to get called automatically when we create new project or create a new activity ? And how is it getting called"
I tried to search it. But not getting the proper answer
I don't know if there's a specific spot in the documentation that explains this clearly, so I can't really cite sources. This is just what I've picked up over time working in Android and looking at source code.
The Android OS is responsible for launching Activities. An Activity is found and launched through an Intent. It could be internally done in your own app. Or if it is the entry point to your app, it could be launched by the home screen launcher app of the device. Or in debugging mode, the OS can be commanded to launch a specific activity (this is what happens when your Run your app from Android Studio).
An Activity must have an empty constructor (a constructor with no arguments) so the OS can create an instance of your Activity using reflection. Since the OS cannot know of all possible Activity classes ahead of time, it must use reflection to find the constructor and call it.
After it has an instance of your Activity, the OS manages its lifecycle. It will call lifecycle functions like onCreate() at the appropriate times in its life. onCreate() is the first time in your Activity's life where you can do Activity- or Context-specific work safely. So, there are restrictions in what you can do in property initializers and init blocks, since these are called before onCreate().
You must never call your Activity's constructor or its lifecycle functions directly yourself. These are reserved for use by the OS.

NightmareJS without closing the browser

I'm used to PhantomJS and Watir, which both provide a REPL out of the box. The REPL lets me execute automation calls on a currently-running browser.
This is a fun way to make automation scripts because I can watch the effect of each step as I build an automation script.
In fact, I can even write a script that defines methods for opening a browser, performing a log-in, and other common tasks, and then call them as I please from within the generic Node or Ruby REPL.
Can I execute NightmareJS calls without closing the browser (Electron)?
Without closing? Yes - don't call .end().
If you're asking if you could disconnect the IPC - meaning the calling program ends but does not end the Nightmare instance - and then pick up the Nightmare instance again somewhere else, the answer is no.
#393 (packaging Nightmare functions with an existing Electron application) and #593 (covering v3 wants, including one Electron instance for many applications) are related, but I'm not convinced attaching IPC from new calling applications is a great idea.
If you provide more information about what your circumstances are and what you're trying to do, I'll edit this answer to try to help.
Having a REPL is a different question - I will add it to my list of things to look into. It's a good idea.

Application State / Test Fixtures with Xcode UI Tests

A pretty common problem with any kind of integration test is getting the unit under test into a known state -- the state that sets up well for the test you want to perform. With a unit test, there's usually not much state, and the only issue is in potentially mocking out interactions with other classes.
On the other hand, when testing a whole app there's all sorts of potentially persistent state, and getting the app into a clean state, or trickier still, into a known state that isn't "clean" without any access to the app itself is a little tricky.
The only suggestion I've found is to embed any necessary setup in the app, and use something like an environment variable to trigger setup. That is, of course, viable, but it's not ideal. I don't really want to embed test code and test data in my final application if I can avoid it.
And then there's mocking out interactions with remote services. Again you can embed code (or even a framework) to do that, and trigger it with an environment variable, but again I don't love the idea of embedding stubbing code into the final app.
Suggestions? I haven't been able to find much, which makes me wonder if no-one is using Xcode UI testing, or is only using it for incredibly simple apps that don't have these kinds of issues.
Unfortunately, the two suggestions you mentioned are the only ones that are possible with Xcode UI Testing in its current state.
There is, however, one thing you can do to mitigate the risk of embedding test code in your production app. With the help of a few compiler flags you can ensure the specific code is only built when running on the simulator.
#if (arch(i386) || arch(x86_64)) && os(iOS)
class SeededHTTPClient: HTTPClientProtocol {
/// ... //
}
#endif
I'm in the middle of building something to make this a little easier. I'll report back when its ready for use.
Regarding setting up the state on the target app there's a solution. Both the test runner app and your app can read and write to the simulator /Library/Caches folder. Knowing that you can bundle fixture data in your test bundle, copy it to the /Library/Caches on setUp() and pass a launch argument to your application to use that fixture data.
This only requires minimal changes to your app. You only need to prepare it to handle this argument at startup and copy over everything to your app container.
If you want to read more about this, or how you can do the same when running on the device, I've actually written a post on it.
Regarding isolating your UI tests from the network, I think the best solution is to embed a web server on your test bundle and have your app connect to it (again you can use a launch argument parameterize your app). You can use Embassy for that.

Setting a "hard-coded" flag in sources during build process

I am developing a (Groovy) application that I build via Gradle (on a Continuous Integration server). That application should be compiled into two versions: one development build (including some features I only want to enable for myself), and one public build (which would not include or just disable those "development features").
One solution to this would be to have something like a global flag directly in the main class of the application, something like static final boolean PUBLIC_RELEASE. Then within my code I could check for that flag and enable or disable a certain feature.
Now in my Gradle build script I could check for an environment variable (set by the Continuous Integration server). If that variable is set, then I could set (i.e. change) the current value of the flag to either true or false before the sources are being compiled.
I am sure that approach would work. However, it does not feel right to modify the sources themselves during the build process. On the other hand I would assume this is kind of a standard task for many software projects.
Is there any "best practice" to deal with this requirement?
Is can work out three way for handling the scenario - ordered in the way I would do that:
Create a dedicated properties file the is filtered during build and added to the final jar. Application behavior is determined by this file on runtime. Basically this is how such scenario is handled, but such file can be modified in jar directly by the user.
Source code filtering, hint ReplaceTokens. This seems the best way of securing the application, since the behavior is compiled into code directly, but also problematic when it comes to filtering.
Configure the behavior of application by passing system properties -D at runtime. There's a possibility that a lot of such properties should be passed so it might be problematic for the end user and the configuration of the application is explicitly exposed.

Hooking windows API functions to intercept dll loading (Windows only)

I want to intercept dll's loading so I can use them. My first idea was to hook GetProcAddress. Surprisingly, by hooking it, I can only intercept calls made within the process that owns my library. (I opened another executables that call GetProcAddress and those calls don't get intercepted) (I guess because it is dynamically compiled against my lib)
Example of the output:
C:\Windows\syswow64\kernel32.dll
Module32NextW
C:\Windows\syswow64\kernel32.dll
CreateToolhelp32Snapshot
C:\Windows\system32\DINPUT.dll
DirectInputCreateW
C:\Windows\SysWOW64\ntdll.dll
DirectDrawCreate
Anyway, what I want to know is where I should start to be able to intercept dlls loading so I can then use their functions.
Basically, I want to be able to call GetModuleInformation for any dll loaded.
First, what are you doing that requires a global hook?
If you want to be notified that a DLL has loaded in any process, you can look into PsSetImageLoadNotifyRoutine, which is a kernel-mode routine.
Despite it being kernel mode, it's not very hard to use and writing a basic driver is pretty fun.
Another way would be to force a load of your library in every process. There are a variety of methods, one of the more legit ones would be Windows Message hooks.
Install a system-wide hook on the LoadLibrary function.
(I have no idea how to use that small comment thing underneath the question so)

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