在所有其他活动中都需要使用外部类中的微调器

Question

My question is how can i put my spinner in an external java class and implement it in all other activities (works as a menu), here is my spinner code:

final Spinner spinner = (Spinner) findViewById(R.id.comboCasino);
        ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.comboCasino, android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);
        spinner.setSelection(0, false);
        // this will be called when you select any item in this spinner
        spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View arg1, int position, long arg3) {
                // get the text at that position
                switch(position) {
                case 0: {
                    Intent NewPost = new Intent(getApplicationContext(), StartingPoint.class);
                    startActivity(NewPost);
                    break; }
                case 1: {
                    Intent NewPost = new Intent(getApplicationContext(), Simmering.class);
                    startActivity(NewPost); 
                    break; }
                case 2: {
                    Intent NewPost = new Intent(getApplicationContext(), LugnerCity.class);
                    startActivity(NewPost);
                    break; }
                case 3: {
                    Intent NewPost = new Intent(getApplicationContext(), Gmunden.class);
                    startActivity(NewPost);
                    break;}
                case 4: {
                    Intent NewPost = new Intent(getApplicationContext(), Salzburg.class);
                    startActivity(NewPost);
                    break; }
                case 5: {
                    Intent NewPost = new Intent(getApplicationContext(), Linz.class);
                    startActivity(NewPost);
                    break; }
                case 6: {
                    Intent NewPost = new Intent(getApplicationContext(), Saalbach.class);
                    startActivity(NewPost);
                    break; }
                case 7: {
                    Intent NewPost = new Intent(getApplicationContext(), Innsbruck.class);
                    startActivity(NewPost); 
                    break;}
                case 8: {
                    Intent NewPost = new Intent(getApplicationContext(), Reutte.class);
                    startActivity(NewPost);
                    break; }
                case 9: {
                    Intent NewPost = new Intent(getApplicationContext(), Bregenz.class);
                    startActivity(NewPost); 
                    break; }
                case 10: {
                    Intent NewPost = new Intent(getApplicationContext(), Kufstein.class);
                    startActivity(NewPost);
                    break; }
                case 11: {
                    Intent NewPost = new Intent(getApplicationContext(), Bratislava.class);
                    startActivity(NewPost);
                    break; }
                }       
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                // TODO Auto-generated method stub  
            }
        });

it shoud be saved for example in menu.java and should be called in every activity, how do i do that correctly? thank you in advance.

Answer 1

If you have the same menu in all your activities, the best way to do this is by creating a superclass that extends Activity and let all your other activities extend this activity.

public class BaseActivity extends Activity { // menu code  }

public class StartingPoint extends BaseActivity { //... } 

Answer 2

1. Create a constructor for menu.java

     menu(Context mcontext){ this.mcontext = mcontext; } 

2. Now in place of getApplicationContext() call it by passing of object of class where you want to use Spinner property.

     Menu object = new Menu(object_of_current_class); object.ShowSpinner(); 

Answer 3

Try creating your own Spinner class:

public class MenuSpinner extends Spinner {

   public MenuSpinner(Context context) {
      super(context);
      ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.comboCasino, android.R.layout.simple_spinner_item);
      adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
      setAdapter(adapter);
      setSelection(0, false);   
      .
      .
      .
   }
}

And then add it in your layout

<com.yourpackage.MenuSpinner
   android:id="comboCasino"
   .
   .
   . />

If you want more detailled information visit http://developer.android.com/training/custom-views/index.html