Android学习笔记之ActionBar Item用法分析

<uses-sdk Android:minSdkVersion="11"/>

<uses-sdk android:targetSdkVersion="11" />

<?xml version="1.0" encoding="utf-8"?><menu xmlns:android="http://schemas.android.com/apk/res/android">  <item android:id="@+id/action_search"     android:icon="@android:drawable/ic_menu_search"     android:title="action_bar_search"     android:showAsAction="ifRoom"     android:actionViewClass="android.widget.SearchView" />  <item android:id="@+id/action_add"     android:icon="@android:drawable/ic_menu_add"     android:title="action_bar_add" />  <item android:id="@+id/action_edit"     android:icon="@android:drawable/ic_menu_edit"     android:showAsAction="always"     android:title="action_bar_edit" />  <item android:id="@+id/action_share"     android:icon="@android:drawable/ic_menu_share"     android:title="action_bar_share"     android:showAsAction="ifRoom" />  <item android:id="@+id/action_sort"     android:icon="@android:drawable/ic_menu_sort_by_size"     android:title="action_bar_sort"     android:showAsAction="ifRoom">    <menu>      <item android:id="@+id/action_sort_size"         android:icon="@android:drawable/ic_menu_sort_by_size"         android:title="action_bar_sort_size"         android:onClick="onSort" />      <item android:id="@+id/action_sort_alpha"         android:icon="@android:drawable/ic_menu_sort_alphabetically"         android:title="action_bar_sort_alpha"         android:onClick="onSort" />    </menu>  </item></menu>

import android.app.Activity;import android.graphics.drawable.Drawable;import android.os.Bundle;import android.view.Menu;import android.view.MenuInflater;import android.view.MenuItem;import android.widget.SearchView;import android.widget.SearchView.OnQueryTextListener;import android.widget.TextView;import android.widget.Toast;/** * This demonstrates idiomatic usage of the Action Bar. The default Honeycomb theme * includes the action bar by default and a menu resource is used to populate the * menu data itself. If you'd like to see how these things work under the hood, see * ActionBarMechanics. */public class ActionBarUsageActivity extends Activity implements OnQueryTextListener {  TextView mSearchText;  int mSortMode = -1;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    mSearchText = new TextView(this);    setContentView(mSearchText);  }  //和加载传统的menu一样，重写onCreateOptionsMenu方法  @Override  public boolean onCreateOptionsMenu(Menu menu) {    MenuInflater inflater = getMenuInflater();    inflater.inflate(R.menu.actions, menu);    SearchView searchView = (SearchView) menu.findItem(R.id.action_search).getActionView();    searchView.setOnQueryTextListener(this);    return true;  }  @Override  public boolean onPrepareOptionsMenu(Menu menu) {    if (mSortMode != -1) {      Drawable icon = menu.findItem(mSortMode).getIcon();      menu.findItem(R.id.action_sort).setIcon(icon);    }    return super.onPrepareOptionsMenu(menu);  }  //和相应传统的menu一样，重写onOptionsItemSelected方法  @Override  public boolean onOptionsItemSelected(MenuItem item) {    Toast.makeText(this, "Selected Item: " + item.getTitle(), Toast.LENGTH_SHORT).show();    return true;  }  // This method is specified as an onClick handler in the menu xml and will  // take precedence over the Activity's onOptionsItemSelected method.  // See res/menu/actions.xml for more info.  public void onSort(MenuItem item) {    mSortMode = item.getItemId();    // Request a call to onPrepareOptionsMenu so we can change the sort icon    invalidateOptionsMenu();  }  // The following callbacks are called for the SearchView.OnQueryChangeListener  // For more about using SearchView, see src/.../view/SearchView1.java and SearchView2.java  public boolean onQueryTextChange(String newText) {    newText = newText.isEmpty() ? "" : "Query so far: " + newText;    mSearchText.setText(newText);    return true;  }  public boolean onQueryTextSubmit(String query) {    Toast.makeText(this, "Searching for: " + query + "...", Toast.LENGTH_SHORT).show();    return true;  }}