Android 抽屉效果的导航菜单实现

Android 抽屉效果的导航菜单实现

抽屉效果的导航菜单

　　看了不少应用，以为这种侧滑的抽屉效果的菜单很好。

　　不用切换到另外一个页面，也不用去按菜单的硬件按钮，直接在界面上一个按钮点击，菜单就滑出来，并且感受能放不少东西。

　　关于实现，搜索了一下，有以下两种：

1.用SlidingDrawer：

http://developer.android.com/reference/android/widget/SlidingDrawer.html

　　可是不知道为何这个类官方不建议再继续用了：

Deprecated since API level 17

2.用DrawerLayout：

http://developer.android.com/reference/android/support/v4/widget/DrawerLayout.html

　　Guide在这里：

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

库的引用

首先，DrawerLayout这个类是在Support Library里的，须要加上android-support-v4.jar这个包。

　　而后程序中用时在前面导入import android.support.v4.widget.DrawerLayout;

　　若是找不到这个类，首先用SDK Manager更新一下Android Support Library，而后在Android SDK\extras\android\support\v4路径下找到android-support-v4.jar，复制到项目的libs路径，将其Add to Build Path.

代码1

　　布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"><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"><!-- The main content view --><!-- main content must be the first element of DrawerLayout because it will be drawn first and drawer must be on top of it --><FrameLayout      android:id="@+id/content_frame"      android:layout_width="match_parent"      android:layout_height="match_parent"/><!-- The navigation drawer --><ListView      android:id="@+id/left_drawer"      android:layout_width="240dp"      android:layout_height="match_parent"      android:layout_gravity="left"      android:background="#111"      android:choiceMode="singleChoice"      android:divider="@android:color/transparent"      android:dividerHeight="0dp"/></android.support.v4.widget.DrawerLayout></RelativeLayout>

　　DrawerLayout的第一个子元素是主要内容，即抽屉没有打开时显示的布局。这里采用了一个FrameLayout，里面什么也没放。

　　DrawerLayout的第二个子元素是抽屉中的内容，即抽屉布局，这里采用了一个ListView。

　　主要的Activity（从官方实例中扒出来的）：

package com.example.hellodrawer;import android.os.Bundle;import android.app.Activity;import android.content.res.Configuration;import android.view.MenuItem;import android.view.View;import android.widget.AdapterView;import android.widget.AdapterView.OnItemClickListener;import android.widget.ArrayAdapter;import android.widget.ListView;import android.support.v4.app.ActionBarDrawerToggle;import android.support.v4.view.GravityCompat;import android.support.v4.widget.DrawerLayout;publicclass HelloDrawerActivity extends Activity{  private String[] mPlanetTitles;  private DrawerLayout mDrawerLayout;  private ActionBarDrawerToggle mDrawerToggle;  private ListView mDrawerList;  @Override  publicvoid onCreate(Bundle savedInstanceState)  {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_hello_drawer);    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);    // init the ListView and Adapter, nothing new    initListView();    // set a custom shadow that overlays the main content when the drawer    // opens    mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow,        GravityCompat.START);    mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,        R.drawable.ic_drawer, R.string.drawer_open,        R.string.drawer_close)    {      /** Called when a drawer has settled in a completely closed state. */publicvoid onDrawerClosed(View view)      {        invalidateOptionsMenu(); // creates call to                      // onPrepareOptionsMenu()      }      /** Called when a drawer has settled in a completely open state. */publicvoid onDrawerOpened(View drawerView)      {        invalidateOptionsMenu(); // creates call to                      // onPrepareOptionsMenu()      }    };    // Set the drawer toggle as the DrawerListener    mDrawerLayout.setDrawerListener(mDrawerToggle);    // enable ActionBar app icon to behave as action to toggle nav drawer
        getActionBar().setDisplayHomeAsUpEnabled(true);    // getActionBar().setHomeButtonEnabled(true);    // Note: getActionBar() Added in API level 11  }  privatevoid initListView()  {    mDrawerList = (ListView) findViewById(R.id.left_drawer);    mPlanetTitles = getResources().getStringArray(R.array.planets_array);    // Set the adapter for the list view
        mDrawerList.setAdapter(new ArrayAdapter<String>(this,        R.layout.list_item, mPlanetTitles));    // Set the list's click listener
        mDrawerList.setOnItemClickListener(new OnItemClickListener()    {      @Override      publicvoid onItemClick(AdapterView<?> parent, View view,          int position, long id)      {        // Highlight the selected item, update the title, and close the        // drawer
                mDrawerList.setItemChecked(position, true);        setTitle(mPlanetTitles[position]);        mDrawerLayout.closeDrawer(mDrawerList);      }    });  }  @Override  protectedvoid onPostCreate(Bundle savedInstanceState)  {    super.onPostCreate(savedInstanceState);    // Sync the toggle state after onRestoreInstanceState has occurred.    mDrawerToggle.syncState();  }  @Override  publicvoid onConfigurationChanged(Configuration newConfig)  {    super.onConfigurationChanged(newConfig);    mDrawerToggle.onConfigurationChanged(newConfig);  }  @Override  publicboolean onOptionsItemSelected(MenuItem item)  {    // Pass the event to ActionBarDrawerToggle, if it returns    // true, then it has handled the app icon touch eventif (mDrawerToggle.onOptionsItemSelected(item))    {      returntrue;    }    // Handle your other action bar items...returnsuper.onOptionsItemSelected(item);  }}

　　比较纠结的是用了Level 11的一个API，这样minSdkVersion就有限制，不能过低。

　　图片资源Android官网示例处提供下载了。

　　程序运行后效果以下：

　　抽屉打开前：

　　抽屉打开后：

代码2

　　今天又看了一下DrawerLayout的类，发现有不少方法能够直接用的。

　　从新试了一下，其实不用上面那么麻烦，随便本身定义一个按钮控制抽屉的打开就行：

　　布局：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:paddingBottom="@dimen/activity_vertical_margin"  android:paddingLeft="@dimen/activity_horizontal_margin"  android:paddingRight="@dimen/activity_horizontal_margin"  android:paddingTop="@dimen/activity_vertical_margin"  tools:context=".DrawerActivity"><android.support.v4.widget.DrawerLayout    android:id="@+id/drawer_layout"    android:layout_width="match_parent"    android:layout_height="match_parent"><!-- The main content view --><FrameLayout      android:id="@+id/content_frame"      android:layout_width="match_parent"      android:layout_height="match_parent"><Button        android:id="@+id/btn"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="open"/></FrameLayout><!-- The navigation drawer --><ListView      android:id="@+id/left_drawer"      android:layout_width="240dp"      android:layout_height="match_parent"      android:layout_gravity="start"      android:background="#111"      android:choiceMode="singleChoice"      android:divider="@android:color/transparent"      android:dividerHeight="0dp"/></android.support.v4.widget.DrawerLayout></RelativeLayout>

　　主要代码：

package com.example.hellodrawer;import android.os.Bundle;import android.app.Activity;import android.support.v4.widget.DrawerLayout;import android.view.Gravity;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;publicclass DrawerActivity extends Activity{  private DrawerLayout mDrawerLayout = null;  @Override  protectedvoid onCreate(Bundle savedInstanceState)  {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_drawer);    mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);    Button button = (Button) findViewById(R.id.btn);    button.setOnClickListener(new OnClickListener()    {      @Override      publicvoid onClick(View v)      {        // 按钮按下，将抽屉打开        mDrawerLayout.openDrawer(Gravity.LEFT);      }    });  }}

参考资料

　　官方教程：

http://developer.android.com/design/patterns/navigation-drawer.html

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

　　其余参考资料：

http://blog.chengyunfeng.com/?p=493

http://my.eoe.cn/appadventure/archive/3826.html