安卓开发之左侧滑动菜单学习

左侧滑动窗口是很多app应用经常用到的，学习它也是很有必要的。

左侧滑动xml的布局：

<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" >

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:clipToPadding="true"
        android:fitsSystemWindows="true" >

        <include
            android:id="@+id/rl_title"
            layout="@layout/layout_main_title" />

        <!-- The main content view -->

        <FrameLayout
            android:id="@+id/content_frame"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_below="@+id/rl_title"
            android:background="@color/white_normal" >
        </FrameLayout>
    </RelativeLayout>

    <!-- The navigation view -->
    <FrameLayout
        android:id="@+id/left_drawer"
        android:layout_width="280dp"
        android:layout_height="match_parent"
        android:layout_gravity="start" >

        <include layout="@layout/layout_main_left" />
    </FrameLayout>

<!--     <ListView -->
<!--     android:id="@+id/left_drawer" -->
<!--     android:layout_width="240dp" -->
<!--     android:layout_height="match_parent" -->
<!--     android:layout_gravity="start" -->
<!--     android:background="#ffffcc" -->
<!--     android:choiceMode="singleChoice" -->
<!--     android:divider="@android:color/transparent" -->
<!--     android:dividerHeight="0dp" > -->
<!--     </ListView> -->

</android.support.v4.widget.DrawerLayout>

include是连接一个新的页面的布局，对于复杂的页面设计，可以起到很好地效果，这样使得结构更清晰，更具有可读性。

FrameLayout是一个框架，也可以把它看着一个activity。上面是一个整体的框架布局，一般把主体部分放在左滑动菜单前面，

这样更利于编辑是区分。

下面是上面xml的效果图：

绿框就是默认的菜单位置。

Main的代码：

package com.ansen.developerheadlines.activity;

import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.widget.DrawerLayout;
import android.view.Gravity;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.WindowManager;
import android.widget.RelativeLayout;

import com.ansen.developerheadlines.R;
import com.ansen.developerheadlines.fragment.ContentFragment;
import com.ansen.developerheadlines.fragment.GiftFragment;
import com.ansen.developerheadlines.fragment.MainFragment;
import com.ansen.developerheadlines.fragment.ShareFragment;

public class MainActivity extends FragmentActivity{
    private DrawerLayout mDrawerLayout;

    private RelativeLayout rlHome, rlGift, rlShare;
    
    private int currentSelectItem = R.id.rl_home;// 默认首页
    
    private MainFragment mainFragment;
    private ShareFragment shareFragment;
    private GiftFragment giftFragment;

//    private ContentFragment contentFragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);

        findViewById(R.id.iv_menu).setOnClickListener(clickListener);
        
        initLeftMenu();//初始化左边菜单
        
//        contentFragment=new ContentFragment();
        mainFragment=new MainFragment();
//        getSupportFragmentManager().beginTransaction().add(R.id.content_frame,contentFragment).commit();  
        getSupportFragmentManager().beginTransaction().add(R.id.content_frame,mainFragment).commit();
        setWindowStatus();
    }

    private void initLeftMenu() {
        rlHome = (RelativeLayout) findViewById(R.id.rl_home);
        rlGift = (RelativeLayout) findViewById(R.id.rl_gift);
        rlShare = (RelativeLayout) findViewById(R.id.rl_share);

        rlHome.setOnClickListener(onLeftMenuClickListener);
        rlGift.setOnClickListener(onLeftMenuClickListener);
        rlShare.setOnClickListener(onLeftMenuClickListener);

        rlHome.setSelected(true);
    }

    private OnClickListener onLeftMenuClickListener = new OnClickListener() {
        @Override
        public void onClick(View v) {
            if (currentSelectItem != v.getId()) {//防止重复点击
                currentSelectItem=v.getId();
                noItemSelect();
                changeFragment(v.getId());//设置fragment显示切换
                switch (v.getId()) {
                case R.id.rl_home:
                    rlHome.setSelected(true);
//                    contentFragment.setContent("这是首页");
                    break;
                case R.id.rl_gift:
                    rlGift.setSelected(true);
//                     contentFragment.setContent("这是礼物");
                    break;
                case R.id.rl_share:
                    rlShare.setSelected(true);
//                     contentFragment.setContent("这是分享");
                    break;
                }
                mDrawerLayout.closeDrawer(Gravity.LEFT);
            }
        }
    };
    
    /**
     * 改变fragment的显示
     * @param resId
//     */
    private void changeFragment(int resId) {
        FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();//开启一个Fragment事务
        
        hideFragments(transaction);//  t
        if(resId==R.id.rl_home){//主页
            if(mainFragment==null){//如果为空先添加进来.不为空直接显示
                mainFragment = new MainFragment();
                transaction.add(R.id.content_frame,mainFragment);
            }else {
                transaction.show(mainFragment);
            }
        }else if(resId==R.id.rl_share){
            if(shareFragment==null){
                shareFragment = new ShareFragment();
                transaction.add(R.id.content_frame,shareFragment);//加入后直接调用了show()显示。
            }else {
                transaction.show(shareFragment);
            }
        }else if(resId==R.id.rl_gift){
            if(giftFragment==null){
                giftFragment = new GiftFragment();
                transaction.add(R.id.content_frame,giftFragment);
            }else {
                transaction.show(giftFragment);
            }
        }
        transaction.commitAllowingStateLoss();//一定要记得提交事务
    }
    
    /**
     * 显示之前隐藏所有fragment
     * @param transaction
     */
    private void hideFragments(FragmentTransaction transaction){
        if (mainFragment != null)//不为空才隐藏,如果不判断第一次会有空指针异常
            transaction.hide(mainFragment);
        if (shareFragment != null)
            transaction.hide(shareFragment);
        if (giftFragment != null)
            transaction.hide(giftFragment);
    }
    
    private void noItemSelect(){
        rlHome.setSelected(false);
        rlGift.setSelected(false);
        rlShare.setSelected(false);
    }

    private OnClickListener clickListener = new OnClickListener() {
        @Override
        public void onClick(View v) {
            switch (v.getId()) {
            case R.id.iv_menu:// 打开左边抽屉
                mDrawerLayout.openDrawer(Gravity.LEFT);
                break;
            }
        }
    };

    // 设置状态栏
    private void setWindowStatus() {
//        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
//            // 透明状态栏
//            getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_STATUS);
//            // 透明导航栏
//            getWindow().addFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
//            // 设置状态栏颜色
//            getWindow().setBackgroundDrawableResource(R.color.main_color);
//        }
    }
}

这些只是部分代码，需要进一步补充才能看到效果。