DrawerLayout官方Demo

/* * Copyright 2013 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.example.android.navigationdrawerexample; import java.util.Locale; import android.app.Activity; import android.app.Fragment; import android.app.FragmentManager; import android.app.SearchManager; import android.content.Intent; import android.content.res.Configuration; import android.os.Bundle; import android.support.v4.app.ActionBarDrawerToggle; import android.support.v4.view.GravityCompat; import android.support.v4.widget.DrawerLayout; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.ArrayAdapter; import android.widget.ImageView; import android.widget.ListView; import android.widget.Toast; /** * This example illustrates a common usage of the DrawerLayout widget * in the Android support library. * <p/> * <p>When a navigation (left) drawer is present, the host activity should detect presses of * the action bar's Up affordance as a signal to open and close the navigation drawer. The * ActionBarDrawerToggle facilitates this behavior. * Items within the drawer should fall into one of two categories:</p> * <p/> * <ul> * <li><strong>View switches</strong>. A view switch follows the same basic policies as * list or tab navigation in that a view switch does not create navigation history. * This pattern should only be used at the root activity of a task, leaving some form * of Up navigation active for activities further down the navigation hierarchy.</li> * <li><strong>Selective Up</strong>. The drawer allows the user to choose an alternate * parent for Up navigation. This allows a user to jump across an app's navigation * hierarchy at will. The application should treat this as it treats Up navigation from * a different task, replacing the current task stack using TaskStackBuilder or similar. * This is the only form of navigation drawer that should be used outside of the root * activity of a task.</li> * </ul> * <p/> * <p>Right side drawers should be used for actions, not navigation. This follows the pattern * established by the Action Bar that navigation should be to the left and actions to the right. * An action should be an operation performed on the current contents of the window, * for example enabling or disabling a data overlay on top of the current content.</p> */ public class MainActivity extends Activity { private DrawerLayout mDrawerLayout; private ListView mDrawerList; private ActionBarDrawerToggle mDrawerToggle; private CharSequence mDrawerTitle; private CharSequence mTitle; private String[] mPlanetTitles; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mTitle = mDrawerTitle = getTitle(); mPlanetTitles = getResources().getStringArray(R.array.planets_array); mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout); mDrawerList = (ListView) findViewById(R.id.left_drawer); // set a custom shadow that overlays the main content when the drawer opens mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START); // set up the drawer's list view with items and click listener mDrawerList.setAdapter(new ArrayAdapter<String>(this, R.layout.drawer_list_item, mPlanetTitles)); mDrawerList.setOnItemClickListener(new DrawerItemClickListener()); // enable ActionBar app icon to behave as action to toggle nav drawer getActionBar().setDisplayHomeAsUpEnabled(true); getActionBar().setHomeButtonEnabled(true); // ActionBarDrawerToggle ties together the the proper interactions // between the sliding drawer and the action bar app icon mDrawerToggle = new ActionBarDrawerToggle( this, /* host Activity */ mDrawerLayout, /* DrawerLayout object */ R.drawable.ic_drawer, /* nav drawer image to replace 'Up' caret */ R.string.drawer_open, /* "open drawer" description for accessibility */ R.string.drawer_close /* "close drawer" description for accessibility */ ) { public void onDrawerClosed(View view) { getActionBar().setTitle(mTitle); invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu() } public void onDrawerOpened(View drawerView) { getActionBar().setTitle(mDrawerTitle); invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu() } }; mDrawerLayout.setDrawerListener(mDrawerToggle); if (savedInstanceState == null) { selectItem(0); } } @Override public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.main, menu); return super.onCreateOptionsMenu(menu); } /* Called whenever we call invalidateOptionsMenu() */ @Override public boolean onPrepareOptionsMenu(Menu menu) { // If the nav drawer is open, hide action items related to the content view boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList); menu.findItem(R.id.action_websearch).setVisible(!drawerOpen); return super.onPrepareOptionsMenu(menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { // The action bar home/up action should open or close the drawer. // ActionBarDrawerToggle will take care of this. if (mDrawerToggle.onOptionsItemSelected(item)) { return true; } // Handle action buttons switch(item.getItemId()) { case R.id.action_websearch: // create intent to perform web search for this planet Intent intent = new Intent(Intent.ACTION_WEB_SEARCH); intent.putExtra(SearchManager.QUERY, getActionBar().getTitle()); // catch event that there's no activity to handle intent if (intent.resolveActivity(getPackageManager()) != null) { startActivity(intent); } else { Toast.makeText(this, R.string.app_not_available, Toast.LENGTH_LONG).show(); } return true; default: return super.onOptionsItemSelected(item); } } /* The click listner for ListView in the navigation drawer */ private class DrawerItemClickListener implements ListView.OnItemClickListener { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { selectItem(position); } } private void selectItem(int position) { // update the main content by replacing fragments Fragment fragment = new PlanetFragment(); Bundle args = new Bundle(); args.putInt(PlanetFragment.ARG_PLANET_NUMBER, position); fragment.setArguments(args); FragmentManager fragmentManager = getFragmentManager(); fragmentManager.beginTransaction().replace(R.id.content_frame, fragment).commit(); // update selected item and title, then close