我刚开始，ActionBar我得到了一个NoSuchMethodError Exception. 这是什么原因？
这是例外
java.lang.NoSuchMethodError: com.example.actionbar2.MainActivity.getActionBar
代码 ：
package com.example.actionbar2;
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.Activity;
import android.app.Fragment;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;
public class MainActivity extends Activity {
public static Context appContext;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//ActionBar gets initiated
ActionBar actionbar = getActionBar();
//Tell the ActionBar we want to use Tabs.
actionbar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
//initiating both tabs and set text to it.
ActionBar.Tab PlayerTab = actionbar.newTab().setText("Fragment A");
ActionBar.Tab StationsTab = actionbar.newTab().setText("Fragment B");
//create the two fragments we want to use for display content
Fragment PlayerFragment = new AFragment();
Fragment StationsFragment = new BFragment();
//set the Tab listener. Now we can listen for clicks.
PlayerTab.setTabListener(new MyTabsListener(PlayerFragment));
StationsTab.setTabListener(new MyTabsListener(StationsFragment));
//add the two tabs to the actionbar
actionbar.addTab(PlayerTab);
actionbar.addTab(StationsTab);
}
public class AFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.afragment, container, false);
}
}
public class BFragment extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.afragment, container, false);
}
}
class MyTabsListener implements ActionBar.TabListener {
public Fragment fragment;
public MyTabsListener(Fragment fragment) {
this.fragment = fragment;
}
@Override
public void onTabReselected(Tab tab, android.app.FragmentTransaction ft) {
Toast.makeText(MainActivity.appContext, "Reselected!", Toast.LENGTH_LONG).show();
}
@Override
public void onTabSelected(Tab tab, android.app.FragmentTransaction ft) {
ft.replace(R.id.fragment_container, fragment);
}
@Override
public void onTabUnselected(Tab tab, android.app.FragmentTransaction ft) {
ft.remove(fragment);
}
}
}