How to prevent android app from being Crash

Question

I want to stop my app from being crashed due to uncaught exception. I want exception to be store in log and prevent application from getting crashed. How do i achieve this ?. Thanks in advance.

Answer 1

For this your just need two classes Just copy paste them . This class is called when any exception occur within your application.

public class CrashHandler implements
        java.lang.Thread.UncaughtExceptionHandler {
    private final Context myContext;
    private final String LINE_SEPARATOR = "\n";

    public CrashHandler(Context context) {
        myContext = context;
    }

    public void uncaughtException(Thread thread, Throwable exception) {
        StringWriter stackTrace = new StringWriter();
        exception.printStackTrace(new PrintWriter(stackTrace));
        StringBuilder errorReport = new StringBuilder();
        errorReport.append("************ CAUSE OF ERROR ************\n\n");
        errorReport.append(stackTrace.toString());

        errorReport.append("\n************ DEVICE INFORMATION ***********\n");
        errorReport.append("Brand: ");
        errorReport.append(Build.BRAND);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("Device: ");
        errorReport.append(Build.DEVICE);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("Model: ");
        errorReport.append(Build.MODEL);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("Id: ");
        errorReport.append(Build.ID);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("Product: ");
        errorReport.append(Build.PRODUCT);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("\n************ FIRMWARE ************\n");
        errorReport.append("SDK: ");
        errorReport.append(Build.VERSION.SDK);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("Release: ");
        errorReport.append(Build.VERSION.RELEASE);
        errorReport.append(LINE_SEPARATOR);
        errorReport.append("Incremental: ");
        errorReport.append(Build.VERSION.INCREMENTAL);
        errorReport.append(LINE_SEPARATOR);

        Intent intent = new Intent(myContext, ExceptionDisplay.class);
        intent.putExtra("error", errorReport.toString());
        intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
        myContext.startActivity(intent);

        android.os.Process.killProcess(android.os.Process.myPid());
        System.exit(10);
    }

}

Now make an Activity that displayed the error :-

public class ExceptionDisplay extends AppCompatActivity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.exception_display_layout);

        TextView exception_text = (TextView) findViewById(R.id.exception_text);
        Button btnBack = (Button) findViewById(R.id.btnBack);
        exception_text.setText(getIntent().getExtras().getString("error"));

        btnBack.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                intentData();
            }
        });
    }

    @Override
    public void onBackPressed() {
        intentData();
    }

    public void intentData() {

        Log.d("CDA", "onBackPressed Called");
        Intent setIntent = new Intent(ExceptionDisplay.this, AppDataSourceSelection.class);
        setIntent.addCategory(Intent.CATEGORY_HOME);
        setIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        startActivity(setIntent);
    }
}

Now you can call this class by the class that extends application Class:

public class ErrorHandler extends Application {


    @Override
    public void onCreate() {
        super.onCreate();
       Thread.setDefaultUncaughtExceptionHandler(new CrashHandler(getApplicationContext()));

        }}