showEnterNameDialog

AlertDialogManager

package com.example.myfunction;

import android.app.AlertDialog;
import android.content.Context;
import android.content.SharedPreferences;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;

public class AlertDialogManager {
	public void showEnterNameDialog(final Context context) {
		final AlertDialog alertDialog = new AlertDialog.Builder(context)
				.create();
		alertDialog.setCancelable(false);
		alertDialog.setTitle("Enter Your Name");

		LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
				LinearLayout.LayoutParams.MATCH_PARENT,
				LinearLayout.LayoutParams.MATCH_PARENT);

		final EditText input = new EditText(context);
		input.setLayoutParams(lp);
		input.setHint("Type here");
		input.setText(context.getSharedPreferences(MainActivity.PREF,
				Context.MODE_PRIVATE).getString(MainActivity.PREF_NAME, ""));

		final Button btn = new Button(context);
		btn.setLayoutParams(lp);
		btn.setText("Confirm");
		btn.setOnClickListener(new Button.OnClickListener() {

			@Override
			public void onClick(View v) {
				if (!input.getText().toString().trim().isEmpty()) {
					SharedPreferences sp = context.getSharedPreferences(
							MainActivity.PREF, Context.MODE_PRIVATE);
					SharedPreferences.Editor se = sp.edit();
					se.putString(MainActivity.PREF_NAME, input.getText()
							.toString().trim());
					se.commit();
					alertDialog.dismiss();
				}
			}
		});

		final LinearLayout ll = new LinearLayout(context);
		ll.setLayoutParams(lp);
		ll.setOrientation(LinearLayout.VERTICAL);
		ll.addView(input);
		ll.addView(btn);
		alertDialog.setView(ll); // uncomment this line

		// Showing Alert Message
		alertDialog.show();
	}
}

MainActivity

package com.example.myfunction;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;


public class MainActivity extends Activity {

    protected static final String PREF = "PREF";
	protected static final String PREF_NAME = "PREF_NAME";

	@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, 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) {
			adm.showEnterNameDialog(MainActivity.this);
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
    
	AlertDialogManager adm = new AlertDialogManager();
	@Override
	public void onResume() {

		if (getSharedPreferences(PREF, Context.MODE_PRIVATE).getString(
				PREF_NAME, "").equals("")) {
			adm.showEnterNameDialog(MainActivity.this);
		}
		super.onResume();
	}
}