Android App Keep On Crashing In API_Lev 23

Question

I am new to android dev

I have made as simple app in android (for api_version greater than 23) which fetches the name of all running apps. But the app doesn't work properly. When I click the button the functionality registered in "onClickListner" is not working.

package com.sakthi.appban;

    import androidx.appcompat.app.AppCompatActivity;
    
    import android.content.pm.ApplicationInfo;
    import android.content.pm.PackageManager;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.Button;
    import android.widget.Toast;
    
    import java.util.List;
    
    public class MainActivity extends AppCompatActivity {
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
    
            Button btn = findViewById(R.id.button);
            btn.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {
                    displayAllApps();
                }
            });
    
        }
    
        private void displayAllApps(){
            PackageManager pm = getPackageManager();
            List<ApplicationInfo> installedApplications = pm.getInstalledApplications(PackageManager.GET_META_DATA);
    
            for(ApplicationInfo application : installedApplications){
                Toast.makeText(this, application.name, Toast.LENGTH_SHORT).show();
                try {
                    Thread.sleep(1000);
    
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
            Toast.makeText(this, "Task Ended", Toast.LENGTH_SHORT).show();
        }

Hope I will get help

Thanks in advance

@ShailendraMadda Yea but I have tested it in my physical device how could I get the log?. — Sakthimahendran, May 29 '21 at 10:43
@ShailendraMadda I have tried your solution but still the problem remains. the app opens and listen for me to click the button but after I click it. the crashed — Sakthimahendran, May 29 '21 at 10:51
@ShailendraMadda This the last lines of the log...... f/art: Thread[3,tid=30657,WaitingInMainSignalCatcherLoop,Thread*=0x7a0157a400,peer=0x12ca1280,"Signal Catcher"]: reacting to signal 3 I/art: Wrote stack traces to '/data/anr/traces.txt' — Sakthimahendran, May 29 '21 at 11:25
How did you install this app on your device? If you are running the app directly from android studio by keeping the USB cable then you can see logs in the log cat. If not then install an external app to get logs after the crash something like https://play.google.com/store/apps/details?id=com.apptiva.logviewer&hl=en_IN&gl=US — Shailendra Madda, May 29 '21 at 11:26
With you log you added above related to ANR https://stackoverflow.com/a/29777311/2462531 — Shailendra Madda, May 29 '21 at 11:33

Shailendra Madda · Answer 1 · 2021-05-29T11:42:09.540

I think you might have seen these message in logs if you run this code you will get this error when you click on the button

Error:

java.lang.IllegalStateException: You must either set a text or a view

Here application.name may get null for some of the apps. This may cause IllegalStateException because you are passing null to a Toast.

To fix this simply add an if condition to null check like this:

if(application.name != null) {
   Toast.makeText(this, application.name, Toast.LENGTH_SHORT).show();
 }

Then it should work.

Update:

You can remove this code from your code which causing ANR:

try {
    Thread.sleep(1000);
} catch (InterruptedException e) {
    e.printStackTrace();
}

score 0 · Accepted Answer · answered May 29 '21 at 11:45

0

The problem is that I am trying to loop in the UI thread. So the UI thread cannot handle the UI operation.. and my program crashed.More info here

answered May 29 '21 at 11:45

Sakthimahendran

24
6

Android App Keep On Crashing In API_Lev 23

2 Answers2