While coding, sometimes we'd like to put some simple print statements at some location just to see some specific behaviour, but, when running android studio, our app is basically running on a physical cellphone(in this case, just considering the cellphone and not an emulator), but, how do I make the print statements print to my computer's terminal?(Currently using ubuntu 16)
Log calls (e.g., Log.d()) are recorded by Logcat. Those messages are visible directly in Android Studio in the Logcat tool window. If you really want to view Logcat in a terminal window, use adb logcat.
Piggy-backing off what #CommonsWare pointed out, you can also use the Run window to see less of the system logs and information more specific to your actual run of the app. This was helpful for me in the beginning but sometimes you need the verbosity of the Logcat window. If you end up using the Logcat window, there should be a search bar at the top of the window that you can use to filter out specific messages.
For example, if you call Log.i(tag, message), you can search for tag in the Logcat window and only those messages will be shown! Hope it helps narrow your search.
Related
When I run my android app, the logcat window fills up and then clears. I have System.out.println()'s that aren't showing up, nothing is showing up and I have no idea why.
EDIT: Using Android Studio
I have had a lot of issues with logcat in Android Studio, so here's a few items:
In your run configuration (just to the left of the play button, select "Edit Configuration" from the drop-down, you can configure a couple of options related to logcat, including whether or not Android Studio will clear it on startup
If the debugger disconnects you will lose your connection to the logcat. (some kinds of errors seem to force disconnect the debugger. I'm not entirely sure why.)
If you never clear your logcat, then Android Studio will attempt to display the entire logcat since the last time you restarted the device/emulator. This can take a long time, and may display a blank screen while it's processing.
By default, Android Studio will try to filter out messages unrelated to your app. In my experience, this never works right. I think it's easier to search for the tag that you're looking for.
I haven't specifically tried System.out.println() in Android Studio, but the typical Android way to print debug messages is with Log.d. Log
is located in android.util.Log. Android Studio will import it automatically if you type Log and press alt+enter.
My guess would be that your problem isn't that it's clearing logcat, but that it's not clearing logcat and Android Studio is choking on too large of a log file. Either select auto-clearing from the run configuration window or try walking away for a few minutes and see if the logcat ever comes back
I'm noticing a strange behaviour when i plug in any android device to my computer.
It starts showing some messages in the LogCat in Eclipse as soon as i plug it in. Same thing with my HTC and ASUS tablet.
This has never happened before and I dont remember doing anything out of ordinary when I developed my app yesterday.
Any1 has an idea how to stop this ?
Thanks in advance
You can add filters to the logcat so that you only show relevant information.
From my experience it's perfectly normal for the logcat to start displaying messages as soon as you plug in a device. At the least it means it's working! ;)
However, once you start building and running your application and picking up errors the specific filter for your application will start displaying which will only show logs pertaining to your app.
It's set by default to switch to your app once an error displays, but you can change that default by going to Preferences > Android > LogCat and changing "Show logcat view..." from "Error" to "Verbose" or whatever works. That way it will switch to showing your application's logs faster. Beyond that, you can do further specific filters.
Hope that helps XD
This can't be stopped as such as the log cat in eclipse will retrieve anything where logging is being done of some sort whether it is an app, or android itself.
You can filter it, I think at the top of the log cat window there is a text field to only show log messages that contain a certain string and If I remember correctly there are also buttons to the right to only show error messages or warning or both etc.
I had the same problem with my Nexus 5. Eclipse wouldn't recognize the device, so I messed around with the device window a bit and then the log cat started to go crazy.
After several reboots, I un-checked the USB debugging option in the phone's Developer settings and re-checked it.
Problem solved.
I think something in the Device window changed when I performed this action, but I'm not certain.
I have got a problem in my logcat screen and the problem is that,whenever I get error from my application I get blank screen in logcat and I am unable to look at the errors and fix them.How do I overcome this sort of issue?
here is my logcat screen:
Update your ADT plugin in Eclipse and right now you are using deprecated Logcat.
Help > Check for Updates
Go to DDMS->Devices and select the device that you are currently working on.
Just Try this command:---
adb shell
echo 1 > /sys/kernel/logger/log_main/enable
I run into that problem sometimes and I suggest:
Make sure you select the "V" tag to prove that why this happened is not because there is really no errors (Since you select the "E" tag).
Install the USB driver from the manufacturer of your device. Although you can connect the phone to PC as an USB storage device without the driver, you can't debug on the phone without it.
In Settings->Applications->Development, check the USB debugging choice to allow you to debug on the phone.
Make sure you have selected the proper device or emulator, not some other emulators or devices.
Sometimes, the logcat shows nothing, even if you have finished these steps above. In this case, click the "Clear" tag(at the top right, with a RED cross), unplug the phone and plug in again.
you have 3 things to do..
start emulator...
then see devices select your avd like Windows-show view-other-android-devices...
then start logcat Windows-show view-other-android-logcat..that's it and it will do..
But First you should see the emulator in devices..
If you can't then in devices click down arrow near camera icon and click on reset adb.
I ran into this issue in the Android Debug Monitor today. The reason this happened to me was because I had set the "maximum number of logcat messages to buffer" under Preferences/Android/LogCat to some very large amount like 50000000000. If you have played with this setting try setting it lower to like 5000. Once I configured mine back down to 50000 I started seeing messages come through LogCat again. You may have to restart things like the Android Debug Monitor, adb, the computer, the emulator, or the phone. At one point or another I tried all of those. Also you should see an error message when you try to configure this setting back to default. I believe it was a Java Null pointer or something. You can safely ignore the message and just check that the configuration worked when you go back into the Debug monitor. Good luck!
Although this question has been asked long before, I am answering for others who might stumble upon this trouble.
In Mars, eclipse 4.5 and linux using GTK 3, if Android Logcat display is missing, add the following in eclipse.ini before --launcher.appendVmargs
--launcher.GTK_version
2
May also refer these posts.
Logcat show invisible messages in Eclipse Mars
Eclipse GUI broken
The log tab is visible in DDMS and I have been logging data using Log.v(...) for many a week now without any problems.
Today, the log data is now longer being displayed in the Log window. Worked, then did a programming change to track a bug and now the log data is no longer showing.
Have tried running the app on an external Android phone, on the Android Simulator and it makes no difference.
Have closed down Eclipse, reloaded and still no change.
The console displays activity but only to the point of starting the activity.
The external phone is set up for debugging - not that this could be a problem since I have the same problem with the simulator
It looks like I have inadvertantly set something incorrectly but can't remember changing anything :-(
Anyone come across this problem before - have looked at previous posts but none seem relevant.
Regards,
Oliver
I had the same problem a while back. I was using the emulator and device for debugging. Apparently you have to select the device listed in the DDMS view whose logs you want to see. My logs were blank because the device that I was expecting logs from was not the one selected.
Hope that helps
Tried this:
https://stackoverflow.com/a/9826502/1238317
Check in your logcat window - TOP RIGHT corner PAUSE button || (Pause
receiving new logcat messages)
Few clicks + eventually restart eclipse (usually works in my case)
Check your LogCat window to see if you are filtering and make sure to set the debug level to Verbose.
There are possible reasons and solutions:
LogCat might have to much in cache, clear the log and see if it fixed the issue
You might need to select the device in the device view (even if it is already selected, try to click on it)
adb is not correctly working anymore, try to kill and start it again
Check if you see output if you use the command line adb logcat
Just go to DDMS perspective and click on the device's name in upper left corner and done your log cat will Start with a BOOm :P
In Android Studio, which I have found to be much more reliable and intuitive than Eclipse, I found this to be a common issue. For me what solves it (device is automatically set when running your app) besides checking code, is to Quit and restart the emulator or Quit Android Studio and Emulator and reopen/restart
Periodically LogCat will stop showing messages even though I am in debug mode. At other times it will display only one line at a time! I have a solution, restart eclipse. But I would like to understand this better. It takes too much time to restart eclipse when this happens. I have seen this behavior on the emulator and connected to a device. Either the LogCat shows one line with no history or nothing.
I was with the same problem and the solutions here didn't work for me. The solution I found is open the DDMS perspective and select the device and the running process on the Devices window. With that done, the LogCat returns to life.
Yes, I can get the normal logcat back by clear the log. Also I uncheck the "Limit console output" in Run/Debug->Console.
I solve these LogCat issues in two different ways:
Clearing the log to fix the one line at a time issue
Opening the devices window (Window -> Show View -> Other -> Android -> Devices), and clicking on the device that I want to view the log for. This seems to force Android to refresh LogCat on that device.
These are much easier options than restarting eclipse, or messing with adb.
I've had that "one line at a time" problem numerous times. I don't know why exactly it happens but there is a very simple fix that works for me every time. Just hit the clear log button. Simple and easy.
I've also had Logcat fail to show messages. Generally this has been due to a problem with the emulator and it required an emulator restart.
In eclipse you need to give more space to log buffer, default is 5000, i set it to 50000 and no have any problems.
Window->preference->android>logcat
maximum num of log message to buffer __ set some number 50k is ok
I'd recommend adjusting the Logcat buffer size and enable workspace application message monitoring in your preferences, mine are set as seen below.
On a real Device (mine is an HTC Desire in question) I've found simply disabling then enabling ADB does not always solve it. What works more often is to disable ADB, close the page (perhaps by back) then to renter the Development page, and re-enable debug mode.
Same here! What worked for me is open DDMS perspective and on devices pane I clicked
reset adb
Click "Display saved filters view" button By showing the two-pane view of your LogCat you'll be able to check the active filter in the left-pane. I once fixed the empty LogCat by selecting "All messages".
When logcat stops displaying log entries, I find that closing Eclipse and re-opening it solves the problem for me.