如何在Android应用中利用DrawerLayout实现一个侧拉菜单栏功能

<&#63;xml version="1.0" encoding="utf-8"&#63;> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
  xmlns:tools="http://schemas.android.com/tools" 
  xmlns:app="http://schemas.android.com/apk/res-auto" 
  android:layout_width="match_parent" 
  android:layout_height="match_parent" 
  tools:context="com.example.lenovo.mydrawerlayout.MainActivity"> 
<android.support.v4.widget.DrawerLayout 
  android:layout_width="match_parent" 
  android:id="@+id/drawer_layout" 
  android:layout_height="match_parent"> 
  <LinearLayout 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:orientation="vertical" 
    > 
    <android.support.v7.widget.Toolbar 
      android:id="@+id/toolbar" 
      android:layout_width="match_parent" 
      android:layout_height="&#63;attr/actionBarSize" 
      android:background="&#63;attr/colorPrimary" 
      app:popupTheme="@style/AppTheme.PopupOverlay" /> 
    <TextView 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="这是主界面" 
      /> 
  </LinearLayout> 
  <LinearLayout 
    android:layout_width="300dp" 
    android:layout_height="match_parent" 
    android:layout_gravity="left" 
    android:background="#f00" 
    > 
    <TextView 
      android:id="@+id/t" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:text="这是侧拉界面" 
      /> 
  </LinearLayout> 
</android.support.v4.widget.DrawerLayout> 
</LinearLayout> 

<resources> 
   <!-- Base application theme. --> 
  <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar"> 
    <!-- Customize your theme here. --> 
    <item name="colorPrimary">@color/colorPrimary</item> 
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item> 
    <item name="colorAccent">@color/colorAccent</item> 
  </style> 
  <style name="AppTheme.NoActionBar"> 
    <item name="windowActionBar">false</item> 
    <item name="windowNoTitle">true</item> 
  </style> 
  <style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" /> 
  <style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" /> 
</resources> 

package com.example.lenovo.mydrawerlayout; 
 import android.os.Bundle; 
import android.support.design.widget.Snackbar; 
import android.support.v4.view.GravityCompat; 
import android.support.v4.widget.DrawerLayout; 
import android.support.v7.app.ActionBarDrawerToggle; 
import android.support.v7.app.AppCompatActivity; 
import android.support.v7.widget.Toolbar; 
import android.view.View; 
import android.widget.TextView; 
public class MainActivity extends AppCompatActivity { 
  @Override 
  protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    //Toolbar代替ActionBar 
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); 
    setSupportActionBar(toolbar); 
    // DrawerLayout 
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
    //Toolbar上面最左边显示三杠图标监听DrawerLayout 
    ActionBarDrawerToggle toggle = new ActionBarDrawerToggle( 
        this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close); 
    drawer.setDrawerListener(toggle); 
    toggle.syncState(); 
    //侧拉页面字体 
    TextView t= (TextView) findViewById(R.id.t); 
    t.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
        Snackbar.make(v, "侧拉页面", Snackbar.LENGTH_LONG) 
            .setAction("Action", null).show(); 
      } 
    }); 
  } 
  @Override 
  public void onBackPressed() { 
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout); 
    if (drawer.isDrawerOpen(GravityCompat.START)) { 
      drawer.closeDrawer(GravityCompat.START); 
    } else { 
      super.onBackPressed(); 
    } 
  } 
}