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Android

How did you do Array Madness Extra Credit (found in 'coding the fun facts' section)?

Hey guys, i was just wondering how you guys went about accomplishing the Array Madness Extra Credit task? Here's how I did it. If you have any constructive criticism, comments, or would like to point out if something is inefficient, weird, or not a good practice, PLEASE LET ME KNOW! Share your methods below and your reasoning!

package com.example.ian.myapplication;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;

import java.lang.reflect.Array;
import java.util.Arrays;


public class MainActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TextView intArrayFwd = (TextView) findViewById(R.id.intArrayFwd);
        TextView intArrayBkwd = (TextView) findViewById(R.id.intArrayBkwd);

        int[] intArray = {0,1,2,3,4,5,6,7,8,9};
        String stringArray = Arrays.toString(intArray);
        intArrayFwd.setText(stringArray);
        StringBuilder stringBuilder = new StringBuilder(stringArray).reverse();
        intArrayBkwd.setText(stringBuilder);
    }
}

This works, almost perfectly, except for the fact that even the brackets are reversed haha. I could've gone about using a loop, but i wanted to see if there were any useful built-in methods that would assist me, and thanks to stackoverflow, i found the very useful class of StringBuild and StringBuffer.

Nick Frankel
Nick Frankel
428 Points

I spent ages trying to think about how to do this without using a loop as the lectures so far don't really cover this. Not much else to say as i'm a newbie too but good work for researching it!

1 Answer

ABRAHAM CHAVEZ REYES
ABRAHAM CHAVEZ REYES
361 Points

package com.example.hp.testlol;

import android.app.Activity; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.ImageButton; import android.widget.TextView;

import java.util.Arrays;

public class Mtest extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_mtest);
    final TextView firs=(TextView)findViewById(R.id.TV);
    final TextView second=(TextView)findViewById(R.id.TV2);
    ImageButton img1= (ImageButton)findViewById(R.id.img1);
    View.OnClickListener listener = new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            int[] numbersArray = { 5,7,3,0,1,2,8,9,4,6 };
            Arrays.sort(numbersArray);
            for (int a = 0; a < numbersArray.length; a++) {
                firs.append(String.valueOf(numbersArray[a]));
            }

            for (int b = numbersArray.length - 1; b > -1; b--) {
                second.append(String.valueOf(numbersArray[b]));

            }

        }
    };
    img1.setOnClickListener(listener);

}




@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.mtest, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

}

this is the way I did it. but when i press the button i get the whole array of numbers at the same time. i wold like to know if someone make just one number at a time not the whole array of numbers at the same click of button.