Develop Reference

Why is attaching gdbserver to a native android app failing?

I am developing a fully native application in using C++ and pure CMake as the build system - no Android Studio involved at all (proof of concept here)
The code builds, apk is generated and can be installed and run via ADB without issue but I cannot get gdbserver64 to attach to the process for debugging.
More details:
App is built against SDK/NDK API level 30
Attempting to debug on an Android 11 emulator instance without Google Play
I can run adb root just fine
Image already includes gdbserver and gdbserver64, attempting to use those
Developer options and USB debugging enebled in emulator
App has android:debuggable="true" in manifest
But every time I try gdbserver64 :5039 --attach $(pidof my.app.id)
I get /bin/sh: <app_pid>: inaccessible or not found
What am I missing? And no, I cannot just move to Android Studio - this is a cross platform project that needs to be buildable using only CMake.

According to my observation, this may be a bug of prebuilt gdbserver. It treats the parameter after --attach as a program name and tries to start it.

It's not really an answer, but in similar configuration to yours I got same error message and unable to overcome this. For me, switching to lldb helped, see e.g.

how to debug a javafx application for android in eclipse

I create a big JavaFX application that works fine in desktop.
In Android, its size is about 20 Mbytes.
Now, for deploying it for Android, I have installed Gluon (JavaFxPorts).
With a small program (using the JavaFX transitions notions, timeline, ...), I have generated an .apk by calling the androidInstall gradle task. That works fine, except I cannot automatically install the .apk file in my phone. I do copy/paste from my desktop to my phone.
BUT, when I want to do the same process with my big application, at the end, my phone screen is already black.
Therefeore, even if this big application works fine on my desktop, it is necessary to debug it for Android on my desktop, too. But, I don't know how to?
What to do with apkDebug gradle task, ..?
gluon+gradle does not provide a kind of Android emulator that allows to finalize the debug on desktop for a smartphone with its specific features (size of screen, landscape orientation). Do you agree?
What is the additional tool that allows to do that?
Moreover,when the application is deployed in the smartphone, does it exist a tool that allows to finalize the debug on smartphone?
Thant you for your response
Note: I have installed Android SDK manager and its AVDM in Eclipse, but with the JavaFX use, it is impossible to use it, isn't it?

Debugging JavaFX projects on Android so far doesn't work on Android emulators.
Command Line
The usual approach is just log messages to the console (i.e. System.out.println() or Log.v()...), and then using adb logcat.
On command line, go to your Android sdk folder, enter into the platform-tools folder and run adb logcat -v threadtime. That will give you all the log messages from your device, so you'll need to find your FXActivity pid there and filter through it.
Another possibility is using Android's monitor under the tools folder, a GUI tool that will allow filtering the console messages.
Eclipse
There is an ADT plugin for Eclipse, that can be installed following this question. This will allow you displaying logCat and device windows among others. Basically this will offer the same options as the monitor tool.
However, this doesn't seem to work with recent versions of logcat.
Android Studio
You can import your gradle project with Android Studio and enable the Android framework, so you can open the Android Monitor, and easily filter the logcat messages, or switch to the monitor tab with live charts of memory, cpu, ...
Black screen
Typically a black screen means you have some exception going on, so you need to use any of the above mentioned logging methods to track it down, solve it and try again.

Phonegap app for iOS without Phonegap Build

So I asked and answered the question [how to do Phonegap 3.0 without Phonegap Build][1]. Now my app is ready for iOS as well (I think) and it's time to start deploying and debugging for that platform.
The formal question: how can I add the iOS platform to a Phonegap 3.0 project?

This answer is still in progress.
Goals I've achieved:
Compiling the project in command line, then running on device or sim using xCode
Attempts failed:
Compiling and running (device/sim) all from the command-line
1. Creation
I could easily add the iOS platform as described in the docs' iOS Platform Guide.
Basically, if the project already exists because you did Android first, this is how you set up the iOS app structure.
$ add platform ios
Then you should add files to the main /www folder if you didn't already have them from your Android work. Then this takes care of creating the app in debug form:
$ cordova prepare //Creates all the necessary source filed
$ cordova compile //Creates an ipa file
//Alternatively, do both in one go with cordova build
2. Deploying to device
But it is completely unclear how to use the command line interface to actually deploy the test app to device or emulator.
When you attach a physical iOS device, and simply try this from the main project folder...
$ cordova run ios
You get a pretty clear answer:
[Error: An error occurred while running the ios project. Targeting a device is not supported currently.
]
So I've resigned myself that for device testing, I must still use xCode. No biggie. However, xCode cannot "refresh" the project by itself after you've updated your files, so in between deploys you must go back to the command-line to recompile the iOS app.
Strangely, when I update my code, I do need to use "cordova run ios" (even with the above error) in order for the the /platforms/ios/www folder to be updated. So this is what works and does not work:
$ cordova run ios
//Rebuilds the app with main /www files successfully,
//then tries to deploy to device and fails in that.
$ cordova prepare ios
//Does not rebuild with main /www files
//(Also does not deploy but that is not its intended function)
And remember that you also need to clean your xCode project in between runs. So the sequence is:
Previous run
Edit your code
In console, do: cordova run ios
In xCode, Menu bar > Product > Clean product
in xCode, Run
3. Deploying to emulator
Still, "deploying to device is not possible" begs the question "What about emulator?"...
The docs page on the 3.0 command-line interface mentions you should enter the command
$ /path/to/my_new_project/cordova/run
This had me all confused. What kind of path is that? From where are you supposed to run it? Is it a nice way of providing a command you can run from anywhere? Why force me to enter my annoyingly long project path for each command?
Confusingly, the run command doesn't work if you actually go to the "platforms/ios/cordova" directory where the run executable is located.
The trick is to be one directory lower, i.e. at the /platforms/ios subfolder of your Cordova app project. There you type "cordova/run". Then in my case it starts building.
4. Install "ios-sim"
But that was not the end of it. I subsequently get an unanticipated error about "ios-sim" not being installed.
[...]
** BUILD SUCCEEDED **
Error: ios-sim was not found. Please download, build and install version 1.5 or greater from https://github.com/phonegap/ios-sim into your path. Or 'brew install ios-sim' using homebrew: http://mxcl.github.com/homebrew/
Fortunately that project webpage has adequate documentation on how to install. However, even after adding the ios-sim directory to my $PATH, when I want to emulate I get the following error.
$ cordova emulate ios
[TypeError: Arguments to path.join must be strings]
This is where I am currently stuck. My path looks exactly like this (all in one line):
export PATH=${PATH}:/Applications/adt-bundle/
sdk/platform-tools:/Applications/adt-bundle/sdk
/tools:%JAVA_HOME%\bin%ANT_HOME%\bin:"/Users/
cool/Library/Developer/iossim"
What am I doing wrong? I've tried with and without doublequotes, and I've even renamed the ios-sim directory to iossim in case the hyphen was the problem. No effect.
So no simulator for now.
5. Install to iOS App Store
This is the point where Phonegap really leaves you out in the woods. Maybe because they want you to use their paid app publishing service, but also because the process of publishing an iOS app is basically soemthing you do using xCode, iOS Developer Portal, and iTunes Connect.
So here that goes:
You need to have all the right certificates and profiles for your app (yes, it's a bunch of incomprehensible virtual documents that all require each other, Apple is like the Soviet Union of app stores).
You request those certificates and profiles in the iOS Developer Portal, save them to disk, then double-click them so that xCode knows you have them and will include them in your app.
This is the docs page for xCode 4 on how to publish your app.
The most counter-intuitive bit is that in order to publish your app, you first have to create an archive of it in xCode (Open your project in xCode > menu bar > Product > Archive).
When the archive is made, you will see it in the Organizer view under the Archives tab. There should be two buttons: Validate and Distribute. Validate checks and includes all your profiles and certificates in the app, and it also checks for errors like a wrong version number.
Distribute does what it says: it sumbits the app to the App Store.
Congratulations! (Now wait five days)

Installing phonegap app to android emulator using windows CLI

I'm trying to install my Phonegap application onto an Android AVD/Emulator. I have launched the AVD and it's registering as 5554:Nexus_S.
When using the Phonegap commands at the Windows prompt I am typing:
phonegap build android
phonegap install android
The output I get says it successfully installed the app onto the device, but it never shows up. This is the output of the install command:
[phonegap] detecting Android SDK environment...
[phonegap] using the local environment
[phonegap] trying to install app onto device
cp: dest file already exists: C:\Users\username\app\platforms\android\assets\www\phonegap.js
[phonegap] successfully installed onto device
I've tried variations of targeting the device using options with no luck:
--device=5554
--target=5554
Any ideas?

I figured it out. You have to specify the --emulator= in the call, so the command looks like:
phonegap install --emulator=emulator-5554 android
You can find the name/id of your running emulators by running the list-started-emulators.bat under the /platforms/android/cordova/lib/ folder in your project.

Another quick note is that sometimes even when you have started the emulator phonegap will not recognize it... so you have to start it from phonegap bat file so that the right process number is registered. to do this.
Use the following command,
1. List-emulator-images.bat : This will display available emulator images you have
2. start-emulator : This will start the emulator which will register with phonegap.
Also make sure you are running all of this from and ADMIN Enabled command prompt.

Okay, I've solved my problem. This solution may not be applied to all, but I was suffering from the same problem as I've mentioned in the comments of the question.
What did I do wrong?
I made some changes in one of the plugins.
I was working on my app and added the Vibration plugin. I made some changes in the plugin, both in the generic version [your_project_root\plugins\org.apache.cordova.vibration\src\android\Vibration.java] and also in the platform specific version [your_project_root\platforms\android\src\org\apache\cordova\vibration\Vibration.java].
But when I reverted the changes back, everything went fine.
I say it again, this solution may not be generic but can be useful for at least my type of problem.
And this gives rise to another question, can't we make changes in the Plugins?I think it is totally fine to make changes in them. Maybe I had done something wrong.

Rebooting android using monkeyrunner

I have this application which I'm testing. I use a script which automatically installs the app but I also want to restart the device. This is important as after the installation I run a monkey-test on the device and all kind of quirks and bugs may arise. To get rid of these I want to restart the phone to get it into some kind of "known state". (These bugs are not only in the app as the phone has been known to suddenly shutdown during the tests)
My installation script is run with jython and I know of the device.reboot() command but this takes almost no time at all (which makes me suspicious) and doesn't work very well. I know there's three arguments: "bootloader", "recovery" and "None" but I can't find the impact these would have on the device.
So my question is, is device.reboot() the right command to use? If yes, what happens when I don't use any arguments with the device.reboot() command and what is the effects of the arguments.
It may be worth mentioning that I run the jython script from a batch command prompt in jenkins. So any batch commands using adb or similar would work just as fine.

device.reboot("None") works on my device