使用 Java 程序碼實現動作欄(Action Bar)

前面一些文章示範如何通過 XML 文件定義動作欄(Action Bar). 這篇文章示範如何使用 Java 程序碼實現動作欄(Action Bar).



像下面修改 Activity 中的 onCreateOptionsMenu(Menu menu) 方法實現動作欄, 同時修改 onOptionsItemSelected(MenuItem item) 的 switch-case 處理對應的數值.

package com.Android3ActionBar;

import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class Android3ActionBarActivity extends Activity {
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
  }

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
  super.onCreateOptionsMenu(menu);
  
  MenuItem menuItem0 = menu.add(0, 0, 0, "done"); 
  //(groupId, itemId, order, title)
  menuItem0.setIcon(R.drawable.ic_action_done);
  menuItem0.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
     |MenuItem.SHOW_AS_ACTION_WITH_TEXT);
  
  MenuItem menuItem1 = menu.add(0, 1, 1, "photo");
  menuItem1.setIcon(R.drawable.ic_action_photo);
  menuItem1.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
     |MenuItem.SHOW_AS_ACTION_WITH_TEXT);
  
  MenuItem menuItem2 = menu.add(0, 2, 2, "refresh");
  menuItem2.setIcon(R.drawable.ic_action_refresh);
  menuItem2.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
     |MenuItem.SHOW_AS_ACTION_WITH_TEXT);
  
  MenuItem menuItem3 = menu.add(0, 3, 3, "star");
  menuItem3.setIcon(R.drawable.ic_action_star);
  menuItem3.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
     |MenuItem.SHOW_AS_ACTION_WITH_TEXT);
  
  MenuItem menuItem4 = menu.add(0, 4, 4, "user");
  menuItem4.setIcon(R.drawable.ic_action_user);
  menuItem4.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
     |MenuItem.SHOW_AS_ACTION_WITH_TEXT);

  MenuItem menuItem5 = menu.add(0, 5, 5, "add user");
  menuItem5.setIcon(R.drawable.ic_action_user_add);
  menuItem5.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM
     |MenuItem.SHOW_AS_ACTION_WITH_TEXT);
  
  return true;
 }

 @Override
 public boolean onOptionsItemSelected(MenuItem item) {
  // TODO Auto-generated method stub
  switch(item.getItemId()){
  case 0:
  case 1:
  case 2:
  case 3:
  case 4:
  case 5:
   Toast.makeText(Android3ActionBarActivity.this,
     item.getTitle(),
     Toast.LENGTH_LONG).show();
   return true;
  default:
   return false;
  }
  
 }

}