Android apps is not starting when i used the sqlite it

Question

The code for the main activity is down below. I started learning the SQL in Android studio. I will answer any further queries.

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    EditText inputField;
    Button insButton,delButton;
    TextView outputField;
    SQLHandler handler;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        inputField=(EditText)findViewById(R.id.input);
        insButton=(Button)findViewById(R.id.insertButton);
        delButton=(Button)findViewById(R.id.deleteButton);
        outputField=(TextView)findViewById(R.id.output);

        showOutput();
    }

    private void showOutput() {
        String text=handler.showName();
        outputField.setText(text);
    }

    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.insertButton:
                USER_DETAILS details=new USER_DETAILS(inputField.getText().toString());
                handler.addName(details);
                inputField.setText("");
                showOutput();
                break;
            case R.id.deleteButton:
                handler.delName(inputField.getText().toString());
                showOutput();
                inputField.setText("");
                break;
        }
    }
}

I have searched but not found any thing in stackoverflow. The error is unable to start the component info and cannot invoke the virtual method. Thank you for time.

can you attach the stacktrace ? – deepakchethan Jun 13 '17 at 00:53 — deepakchethan, Jun 13 '17 at 00:53

score 0 · Accepted Answer · answered Jun 13 '17 at 00:56

Seems like you forgot to instantiate the DBhandler, if you did add it in the main activity. So the code will be,

 protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
         handler=new SQLHandler(this);
        inputField=(EditText)findViewById(R.id.input);
        insButton=(Button)findViewById(R.id.insertButton);
        delButton=(Button)findViewById(R.id.deleteButton);
        outputField=(TextView)findViewById(R.id.output);
        showOutput();
    }

Change the arguments for the SQLHandler() according to your class.

Android apps is not starting when i used the sqlite it

1 Answers1