I made some small changes to my android app (moved a library locally, upgraded gradle plugin to last, ...) and now if I use "minifyEnabled true", my app freezes at start:
I/WindowManager: Input event dispatching timed out sending to
net.myapp/net.myapp.view.mView. Reason: Waiting to send non-key event
because the touched window has not finished processing certain input
events that were delivered to it over 500.0ms ago. Wait queue length:
5. Wait queue head age: 5520.8ms.
And if I touch the screen, I get:
I/InputDispatcher: Dropped event because it is stale.
Besides that, I cannot see anything in the logs.
Setting minifyEnabled to false works. How can I find the exact source of the problem?
So, trying to understand the reason of my problem, I removed proguard. Then I had the methods limit of dex (random errors saying it could not find methods and classes of my app) and moved to multidex and everything solved.
So I'm not sure this was the problem, but if it may help someone you can refer to this: https://developer.android.com/studio/build/multidex.html#mdex-gradle
I am getting following error logs on some phone which as follow:
Reason: Input dispatching timed out (Waiting to send non-key event because the touched window has not finished processing certain input events that were delivered to it over 500.0ms ago. Wait queue length: 20. Wait queue head age: 5509.1ms.)
I am using Retrofit 2 for networking calls in which I use async method, Using database as realm where I used async transaction for writing stuff.
Using Glide for image loading.
On using Strict Mode I found out I get penalty log for shared preferences nothing else. Any other pointers to see and debug issue
Any types of time expensive procedure like data syncing through network shouldn't do in main thread. Android has some default built-in methods like AsyncTask, IntentService etc. those are on worker thread. Personally I have not good idea about Retrofit 2. If it works on main thread, that case you should use it in a separate thread.
I have searched on the internet regarding what an ANR is. And I studied those references as well. But I don't get details regarding a crash in Android.
Can someone tell me the difference between ANR(Android not Responding) and a crash in Android?
ANR stands for Application Not Responding.
An ANR will occur if you are running a process on the UI thread which takes a long time, usually around 5 seconds. During this time the GUI (Graphical User Interface) will lock up which will result in anything the user presses will not be actioned. After the 5 seconds approx has occurred, if the thread still hasn't recovered then an ANR dialogue box is shown informing the user that the application is not responding and will give the user the choice to either wait, in the hope that the app will eventually recover, or to force close the app.
A crash is when an exception within the app has been thrown which has not been handled. For example, if you try to set the text of an EditText component, but the EditText is null and there is no try catch statement to catch the exception that your app will crash and will be force closed. The user will not see what caused the crash, they will be shown a dialogue telling that the app has force closed unexpectedly and will give them the option to send a bug report. In this example if you were to look in the bug report you would see the error caused by java.lang.NullPointerException.
ANR (Application Not Responding) is due to handling a long running task in the main (UI) thread. If the main thread is stopped for more than 5 seconds, the user will get an ANR.
Crashes are due to exceptions and errors like NullPointerException, ClassNotFoundException, typecasting or parsing errors, etc. ANR also causes a crash of the application.
Note: Never perform a long-running task on the UI thread.
Reference ANR
ANR and Crash Examples:
This question already has an accepted answer, but I am adding 2 simple examples to understand ANR and Crash better.
ANR:
// this will produce an ANR on your app
int i = 0;
while(true) {
i++;
}
Crash:
// this will crash your app : will produce java.lang.ArithmeticException
int value = 5, i = 0;
int result = value / i;
Application Not Responding (ANR):
ANR will display in the following conditions:
Response to the input event (such as key press or screen touch even) within 5 Sec.
A Broadcast Receiver hasn’t finished executing within 10 Sec.
How to avoid ANRs?
Create a different worker thread for long running operations like database operations, network operations etc.
Reinforce Responsiveness:
In android app usually, 100 to 200 ms is the threshold beyond which user will feel that app is slow. Following are the tips through which we can show application more responsive.
Show progress dialog whenever you are doing any background work and a user is waiting for the response.
For games specifically, do calculations for moves in the worker thread.
Show splash screen if your application has time-consuming initial setup.
Crash:
The crash is unhandled condition into the application and it will forcefully close our application. Some of the examples of crashes are like Nullpointer exception, Illegal state exception etc.
ANR stands for Application Not Responding, which means that your app does not register events on the UI Thread anymore because a long running operation is executed there
ANR: It is called when anything your application is doing in the UI thread that
takes a long time to complete (5 sec approx)
Reference: ANR
Crash: It is called when your Application gets some Error or Exception raised by the DVM
ANR also caused by-
No response to an input event (such as key press or screen touch events) within 5 seconds.
A BroadcastReceiver hasn't finished executing within 10 seconds.
ANR stands for Application Not Responding and its occurs when long operation takes place into Main thread......
Crash are due to exception and error like Nullpoint,
ANR stands for Application Not Responding.
It can occur due to many reasons like if an application blocks on some I/O operation on the UI thread so the system can’t process incoming user input events. Or perhaps the app spends too much time building an elaborate in-memory structure or computing the next move in the UI thread.
Blocking the main thread, won't result in a crash, but a popup will be displayed to let users kills the app after 5 seconds.
But For Crash, the main reason is the human errors.
Most of the time an app crashes is because of a coding/design error made by human
Human Errors
Lack of testing
Null Pointer exception
OutofMemory
Example :
This is common when a programmer makes a reference to an object or variable that does not exist, basically creating a null-pointer error.
If you have a bad connection, that can also make your apps crash. The app could also have memory management problems.
Please see my answer for the type of android specific exception which may cause the crash.
Android Specific Exception
ANR for ex: if You are downloading huge amount data in ui thread, meny other possibilities like insufficient memory etc it will come.. probably it leads to crashes in android , We can't say both are same one follows other
[ANR and Crash Different][1]
Android applications normally run entirely on a single thread by default the “UI thread” or
“main thread”. This means anything your application is doing in the UI thread that takes a long time to complete can trigger the ANR dialog because your application is not giving itself a chance to handle the input event or intent broadcasts.
ANR: Basically due to a long running task on main thread.
There are some common patterns to look for when diagnosing ANRs:
The app is doing slow operations involving I/O on the main thread.
The app is doing a long calculation on the main thread.
The main thread is doing a synchronous binder call to another process, and that other process is taking a long time to return.
The main thread is blocked waiting for a synchronized block for a long operation that is happening on another thread.
The main thread is in a deadlock with another thread, either in your process or via a binder call. The main thread is not just waiting for a long operation to finish, but is in a deadlock situation.
The following techniques can help you find out which of these causes is causing your ANRs.
CRASH:
Reason for crashs can be many. Some reasons are obvious, like checking for a null value or empty string, but others are more subtle, like passing invalid arguments to an API or even complex multithreaded interactions
This is good article at developer portal.
It gives clarity in detail about ANR.
https://developer.android.com/training/articles/perf-anr.html
I am new in android and working on a maintenance project
Application crashes if no internet connection while creating Soap Request
Following is screenshot of LogCat, Can any body tell me Whats the reason for crashing.
Amit Battan
You are getting a ANR. It stands for Application Not Resoponding.
Android kills applications which are unresponsive to user interactions. Basically when you are doing heavy processing and the user clicks on a button if your application doesn't respond to the click event within 5 seconds.
In your case, if the internet connection is not there I think your application keeps trying to connect and never comes out of this. Hence the ANR. Consider having a timeout for the request..
Check this link for more details on ANR.
ANR happens when some long operation takes place in the "main" thread. This is the event loop thread, and if it is busy, Android cannot process any further GUI events in the application, and thus throws up an ANR dialog.
Any task that will take more time should not be performed in the UI thread, and should be moved to either an AsyncTask or a Thread & Handler.
Check the /data/anr/traces.txt file.
put the all the downloading task in a thread and check that once....
Actually android allocates some time to every process if the process does not complete its action in that particular time then ANR error will come.
If I wish to debug some code for a UI event, e.g.
public boolean onTouchEvent(MotionEvent me)
{
// code to be debugged
}
... and I hold onto this thread (UI):
After 5 seconds I will get this warning: Key dispatching timed out sending to com.hos/com.hos.MyActivity ... null to Window ...
After 20 seconds I will get: Key dispatching timed out sending to com.hos/com.hos.MyActivity ... null to Window ... Continuing to wait for key to be dispatched
After 35 seconds I will get: Key dispatching timed out sending to com.hos/com.hos.MyActivity ... null to Window ... timed out expired process next Key & find new target
At this point, not only is my application frozen but so is the phone. Quite often I need to wait for the ANR and sometimes hard restart the phone.
Is there a way to debug this code for more than 35 seconds without freezing the app / phone?
If your processing may take more than milliseconds to process you may want to consider launching the processing in another thread which has access to a handler in the main thread.
Once you are done processing, you can then pass a message over to your handler which will then execute on the UI thread. This will help prevent those errors from coming up as well as make debugging your code easier.
If you are looking for an automated UI testing framework, perhaps you could look into integrating Robotium into your project.