Android利用DrawerLayout实现抽屉效果详解编程语言

官网guide:http://developer.android.com/training/implementing-navigation/nav-drawer.html

官网示例:NavigationDrawer.zip  

android.support.v4.widget.DrawerLayout 抽屉layout。该widget只能实现从左向右、从右向左

   openDrawer(), closeDrawer(), isDrawerOpen()

下面贴一下示例的主要的布局文件 和 activity实现

activity_main.xml

    <android.support.v4.widget.DrawerLayout   
        xmlns:android="http://schemas.android.com/apk/res/android"   
        android:id="@+id/drawer_layout"   
        android:layout_width="match_parent"   
        android:layout_height="match_parent">   
       
        <FrameLayout   
            android:id="@+id/content_frame"   
            android:layout_width="match_parent"   
            android:layout_height="match_parent" />   
       
        <ListView   
            android:id="@+id/left_drawer"   
            android:layout_width="240dp"   
            android:layout_height="match_parent"   
            android:layout_gravity="right"   
            android:choiceMode="singleChoice"   
            android:divider="@android:color/transparent"   
            android:dividerHeight="0dp"   
            android:background="#111"/>   
        <!--    
            android:choiceMode  选中状态 跟itemclick没有冲突   
                    none              值为0,表示无选择模式;    
                    singleChoice      值为1,表示最多可以有一项被选中;   
                    multipleChoice    值为2,表示可以多项被选中。   
                       
            android:layout_gravity  left或right  left或start   right或end   
                表示在抽屉里的效果是从左到右还是从右到左出现   
         -->   
    </android.support.v4.widget.DrawerLayout>  

    package com.stone.drawerlayout;   
    /*  
     * 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.  
     */   
       
    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);//抽屉里的view   
       
            // set a custom shadow that overlays the main content when the drawer opens   
            mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START);//设置shadow   
            // 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   需要api level 11   
            getActionBar().setDisplayHomeAsUpEnabled(true);//给home icon的左边加上一个返回的图标   
            getActionBar().setHomeButtonEnabled(true); //需要api level 14  使用home-icon 可点击   
       
            // ActionBarDrawerToggle ties together the the proper interactions   
            // between the sliding drawer and the action bar app icon   
            mDrawerToggle = new ActionBarDrawerToggle(//v4控件  actionbar上的抽屉开关   
                    this,                  /* host Activity */   
                    mDrawerLayout,         /* DrawerLayout object */   
                    R.drawable.ic_drawer,  /* nav drawer image to replace 'Up' caret */     //上一级图标 返回图标   
                    R.string.drawer_open,  /* "open drawer" description for accessibility */   
                    R.string.drawer_close  /* "close drawer" description for accessibility */   
                    ) {   
                public void onDrawerClosed(View view) {//抽屉关闭后   
                    getActionBar().setTitle(mDrawerTitle);   
                    invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()   
                }   
       
                public void onDrawerOpened(View drawerView) {//抽屉打开后   
                    getActionBar().setTitle(mTitle);   
                    invalidateOptionsMenu(); // creates call to onPrepareOptionsMenu()   
                }   
                   
                @Override   
                public boolean onOptionsItemSelected(MenuItem item) {   
                    if (item != null && item.getItemId() == android.R.id.home) {//actionbar上的home icon   
                        //END即gravity.right 从右向左显示   START即left  从左向右弹出显示   
                        if (mDrawerLayout.isDrawerVisible(GravityCompat.END)) {   
                            mDrawerLayout.closeDrawer(GravityCompat.END);//关闭抽屉   
                        } else {   
                            mDrawerLayout.openDrawer(GravityCompat.END);//打开抽屉   
                        }   
                        return true;   
                    }   
                    return false;   
                }   
            };   
            mDrawerLayout.setDrawerListener(mDrawerToggle);//设置抽屉监听   
       
            if (savedInstanceState == null) {   
    //            selectItem(0);   
            }   
        }   
       
        @Override   
        public boolean onCreateOptionsMenu(Menu menu) {//加载menu  sdk3.0以后menu包含在actionbar中   
            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);//search的显示与drawer的显示相反   
            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);   
            }   
        }   
           
      //内容区显示PlanetFragment   
        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 the drawer   
    //        mDrawerList.setItemChecked(position, true);   
    //        setTitle(mPlanetTitles[position]);   
            mDrawerLayout.closeDrawer(mDrawerList);   
        }   
       
        @Override   
        public void setTitle(CharSequence title) {   
            mDrawerTitle = title;   
            getActionBar().setTitle(mDrawerTitle);   
        }   
       
        /**  
         * When using the ActionBarDrawerToggle, you must call it during  
         * onPostCreate() and onConfigurationChanged()...  
         */   
       
        @Override   
        protected void onPostCreate(Bundle savedInstanceState) {   
            super.onPostCreate(savedInstanceState);   
            // Sync the toggle state after onRestoreInstanceState has occurred.   
            mDrawerToggle.syncState();   
        }   
       
        @Override   
        public void onConfigurationChanged(Configuration newConfig) {   
            super.onConfigurationChanged(newConfig);   
            // Pass any configuration change to the drawer toggls   
            mDrawerToggle.onConfigurationChanged(newConfig);   
        }   
       
        /**  
         * Fragment that appears in the "content_frame", shows a planet  
         */   
        public static class PlanetFragment extends Fragment {   
            public static final String ARG_PLANET_NUMBER = "planet_number";   
       
            public PlanetFragment() {   
                // Empty constructor required for fragment subclasses   
            }   
       
            @Override   
            public View onCreateView(LayoutInflater inflater, ViewGroup container,   
                    Bundle savedInstanceState) {   
                View rootView = inflater.inflate(R.layout.fragment_planet, container, false);   
                int i = getArguments().getInt(ARG_PLANET_NUMBER);   
                String planet = getResources().getStringArray(R.array.planets_array)[i];   
                //查找出 res-drawable资源的id   
                int imageId = getResources().getIdentifier(planet.toLowerCase(Locale.getDefault()),   
                                "drawable", getActivity().getPackageName());   
                ((ImageView) rootView.findViewById(R.id.image)).setImageResource(imageId);   
                getActivity().setTitle(planet);   
                return rootView;   
            }   
        }   
    }  

原创文章,作者:奋斗,如若转载,请注明出处:https://blog.ytso.com/tech/pnotes/10706.html

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