Question

menu item is not displaying dialog box below is my code when user click on menu item it should take him to login page where to add that code.

public boolean onOptionsItemSelected(MenuItem item, int id) {
    switch (item.getItemId()) {
        case R.id.Login:
             startActivity(new Intent(this, Login.class));
             return true;
        case R.id.About:
         startActivity(new Intent(this, About.class));
            return true;
        case R.id.Post_Ads:
            AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setMessage("Are you sure you want to exit?")
                   .setCancelable(false);
            AlertDialog alert = builder.create();
                    alert.show();
                    startActivity(new Intent(this, Login.class));
             return true;


          }
    return super.onOptionsItemSelected(item);
}

Answer 1

Try this , it should work:

public boolean onOptionsItemSelected(MenuItem item) {
            // TODO Auto-generated method stub
            switch (item.getItemId()) {
            case R.id.Login:
                Toast.makeText(getApplicationContext(), "Fired 1", Toast.LENGTH_SHORT).show();
                 startActivity(new Intent(this, Login.class));
                 return true;

            case R.id.About:
    Toast.makeText(getApplicationContext(), "Fired 2", Toast.LENGTH_SHORT).show();
             startActivity(new Intent(this, About.class));

                return true;
                        case R.id.Post_Ads:
                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setMessage("Are you sure you want to exit?")
                       .setCancelable(false);
                AlertDialog alert = builder.create();
                        alert.show();
                        startActivity(new Intent(this, Login.class));

                 return true;


              }
        return super.onOptionsItemSelected(item);

        }

There is no method called public boolean onOptionsItemSelected(MenuItem item, int id) in the Activity class to handle option menu's.

The method to handle such events is onOptionsItemSelected(MenuItem).

For your menu items to getting displayed, you have to use following method too,
Check whether you have implemented this method also or not,

public boolean onCreateOptionsMenu(Menu menu) {
    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.your_menu_file, menu);
    return true;
}

And a small correction,

You have implemented the following Alertdialog method,

AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setMessage("Are you sure you want to exit?")
                   .setCancelable(false);
            AlertDialog alert = builder.create();
                    alert.show();
                    startActivity(new Intent(this, Login.class));

You haven’t provided any ok or cancel button here,
And also you made it setCancellable(false). So User cannot choose any options here.

So i am suggesting you to give Ok and Cancel Button here and do what you want to do inside the onClick() method. Like the following example:

AlertDialog.Builder builder = new AlertDialog.Builder(this);
            builder.setMessage("Are you sure you want to exit?")
                   .setCancelable(false);
            AlertDialog alert = builder.create();
            alert.setButton("Ok", new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog, int which) {
                    // Do call some activity or close the app. Do what you wish to;

                }
            });

alert.setButton2("Cancel", new DialogInterface.OnClickListener() {

                public void onClick(DialogInterface dialog, int which) {
                    // Do stay in the current activity or something else. Do what you wish to;

                }
            });
                    alert.show();

             return true;

Hope, It might be helpful.