Missing logcat messages

Question

I have two classes, A1 and A2. Both inherit from BaseActivity, which, in turn, inherits from AppCompatActivity.

BaseActivity has a boatload of logging statements that track, e.g., activity lifecycle methods. Like this: Log.d(tag, "in onCreate");

Those messages are logged, as expected, from A1 but not from A2! I've tried monitoring logcat both from AS and from command line. I can repeat the problem on several Android emulators and in a couple of dev environments.

If I simply replace, e.g., Log.d(tag, "in onCreate") with System.out.println(tag + ": in onCreate"), all of the expected messages appear.

Totally mystified, at this point. Anybody got any suggestions about where my log messages are going?

Edited to add:

I have replaced all calls to Log.d with calls to the following method:

private void log(String message) {
    Log.d("LOGGER", tag);
    Log.d(tag, message);
    System.out.println(tag + ": " + message);
}

Here is sample output from the two subclasses:

07-09 10:26:42.036 9657-9657/net.callmeike.android.latest D/LOGGER: A1
07-09 10:26:42.036 9657-9657/net.callmeike.android.latest D/A1: in onCreate
07-09 10:26:42.036 9657-9657/net.callmeike.android.latest I/System.out: A1: in onCreate

07-09 10:27:10.837 9657-9657/net.callmeike.android.latest D/LOGGER: A2
07-09 10:27:10.837 9657-9657/net.callmeike.android.latest I/System.out: A2: in onCreate

It appears that the variable tag is, in fact, the thing that drives the issue. Anybody understand why?

FWIW:

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="false"
    android:theme="@style/AppTheme"
    >
    <activity
        android:name=".A1"
        android:label="@string/a1_name"
        android:theme="@style/AppTheme.NoActionBar"
        >
    </activity>

    <activity
        android:name=".A2"
        android:label="@string/a2_name"
        android:theme="@style/AppTheme.NoActionBar"
        >

        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
</application>

EDITED to add: Sources for the three Activity-related classes:

public abstract class BaseActivity extends AppCompatActivity {
    private final String tag;
    private final int layout;

    public BaseActivity(String tag, int layout) {
        this.tag = tag;
        this.layout = layout;
    }

    protected abstract void test();

    @Override
    protected final void onCreate(Bundle savedInstanceState) {
        Log.d(tag, "in onCreate");
        super.onCreate(savedInstanceState);
        setContentView(layout);

        setSupportActionBar(findViewById(R.id.toolbar));

        findViewById(R.id.fab).setOnClickListener(this::makeSnackbar);
    }

    final void makeSnackbar(View v) {
        Snackbar.make(v, R.string.action_test, Snackbar.LENGTH_LONG)
            .setAction(R.string.action_test, v1 -> test())
            .show();
    }

    // blah blah blah
}

// BaseActivity logs show up in logcat
public class A1 extends BaseActivity {
    private static final String TAG = "A1";

    public A1() {
        super(TAG, R.layout.activity_a1);
    }

    @Override
    protected void test() {
        // blah blah blah
    }
}

// BaseActivity logs do not show up in logcat
public class A2 extends BaseActivity {
    private static final String TAG = "A2";

    public A2() {
        super(TAG, R.layout.activity_a2);
    }

    @Override
    protected void test() {
        // blah blah blah
    }
}

Can you post your java src to show how you define the classes `A1` and `A2`? — Zakir, Jul 09 '17 at 02:16
Try `protected abstract String getTag();` and `protected abstract int getLayout();` — OneCricketeer, Jul 09 '17 at 02:46
@cricket_007 That sound like a pretty wild guess. Can you support it in any way? — G. Blake Meike, Jul 09 '17 at 03:24
Android uses reflection when creating an Activity so having no constructor is the ideal thing specially when the Android OS decides to recreate the activity. — Enzokie, Jul 09 '17 at 04:29
It's an educated guess that your subclass's tags are not being used therefore you only see "one" type of logging — OneCricketeer, Jul 09 '17 at 05:15
to find out if @cricket_007 hypothesis is corect: does the layout assingnment work as expected? what do you get if you log as `Log.d(getClass().getSimpleName(), "in onCreate");` does `A2.onCreate()` calll `super.onCreate()` ? — k3b, Jul 09 '17 at 07:24
@Enzokie There is no such thing as "no constructor" in Java. — G. Blake Meike, Jul 09 '17 at 14:24
@k3b If I do as you suggest, all logging messages will have the tag "BasicActivity", of course. Also, neither A1 nor A2 override `onCreate`, as you can see from the code. — G. Blake Meike, Jul 09 '17 at 14:26
@cricket_007 Got it. Thanks for the guess. It is not correct, though. — G. Blake Meike, Jul 09 '17 at 14:27
@G.BlakeMeike Thanks for the correction, what I mean is a Default Constructor. — Enzokie, Jul 09 '17 at 14:32
Actually, getClass returns the current class,always. Not the super class. https://stackoverflow.com/questions/3294656/how-to-get-the-parent-base-class-object-super-getclass — OneCricketeer, Jul 09 '17 at 16:29
bam! You are totally correct. Just tried it. I get messages tagged "A1" and none tagged "A2". — G. Blake Meike, Jul 09 '17 at 17:05

score 5 · Accepted Answer · answered Jul 15 '17 at 05:46

5

I've had a similar issue - some of my log messages were not shown by the Log command.
I've found out that there are some "illegal" tags that the logcat won't show.
In my case it was "SMS" tag. Try to change the bad tags with other ones.
You can take a look here - LogCat won't show my logs.
I've searched the documentation, but could not find any list of "illegal" tags.

answered Jul 15 '17 at 05:46

TDG

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Congrats, @TDG. That is, apparently it. I mean WTF? There are some things that you just can't get the Logger to say? Good grief. Here's a thought: In addition to "SMS", it won't log "AT". I wonder if there is some security risk in allowing logging modem command? Many thanks. This was driving me crazy. – G. Blake Meike Jul 17 '17 at 14:49

Missing logcat messages

1 Answers1