???????ActionBar????
????ActionBar??androiD3.0???????????????????????javascript:;" onClick="javascript:tagshow(event, '??ó???');" target="_self">??ó???????????????λ?ò?????????????????????????????????????????ActionBar??????????????????????????????ActionBar?????
??????????????????????????ActionBar??????4??????????????????

????1??App icon???????????App??Logo???????????治????????棬?????????????????
????2??View Control???????л?????????????????????????app??????
????3??Action Buttons????????app??????????????????????actionbar?з???????????Action overflow?У??????????????????????????????Action Buttons???????????ActionBar??50%??
????4??Action overflow????????????????????????????
?????????ActionBar????????????????????????????ActionBar??
????????ActionBar?????
???????actionbar??android3.0??????????????????API Level 11???μ?汾???actionBar??????????v7???????????????????????汾?????????????????????????????????????ActionBar???
????1??????Activity????ActionBarActivity
????2????app????Activity???????????@style/Theme.AppCompat.Light
??????????г?????????????Ч?????

?????????????ActionBar??????????????????????
????//???ActionBar????
????ActionBar actionBar=getSupportActionBar();
????//????hide??????????actionbar
????actionBar.hide();
????//????show????????actionbar
????//actionBar.show();
????????actionBar??????????????App icon???????????????????????????????????????????Logo???????????????????????????????????????????￡?
????1???????????????????????setDisplayHomeAsUpEnabled(Boolean flag)
????2?????????????????????setHomeAsUpIndicator
????3???????????????????дonOptionsItemSelected?????????????ж?
????if(id==android.R.id.home){
????Toast.makeText(this??"???????????"??Toast.LENGTH_SHORT).show();
????return true;
????}
????Ч??????￡?

????Logo???????????
????1??Logo????????????
????setDisplayShowHomeEnabled(Boolean flag)
????setDisplayUseLogoEnabled(Boolean flag)
????2??Logo???????setLogo
???????ú?Ч??????￡?

?????????????View Control??????????????????????????????????????Spinner??tabs??ShareActionProvider??????????????????????????View????????????????????????????????????′????????????????
?????????????
????1??????????????setDisplayShowTitleEnabled(Boolean flag)
????2????????????setTitle
????3???????????setSubtitle
????4???趨?????View??setCustomView
???????Ч?????????


 

????Action Buttons??Action flow????????????????????????????????????ν?????????????actionbar?????
?????????????????????????
????1????дonCreateOptionsMenu???????????????????????????????????????дxml??????????????java?????????????????????дxml??
????2????дonOptionsItemSelected???????????????????????
????Xml???????￡?
????<menu xmlns:android="http://schemas.android.com/apk/res/android"
????xmlns:app="http://schemas.android.com/apk/res-auto"
????xmlns:tools="http://schemas.android.com/tools"tools:context=".MainActivity">
????<item android:id="@+id/action_search"android:title="????"
????android:orderInCategory="100"app:showAsAction="always"
????android:icon="@drawable/ic_launcher"/>
????<item android:id="@+id/action_share"android:title="????"
????android:orderInCategory="100"app:showAsAction="never"/>
????<item android:id="@+id/action_collection"android:title="???"
????android:orderInCategory="100"app:showAsAction="never"/>
????<item android:id="@+id/action_font"android:title="?????С"
????android:orderInCategory="100"app:showAsAction="never"/>
????</menu>
????ShowAsAction???????????????????????????????????????never??always??ifroom??
????Ч?????￡?