package cn.edu.nhic.wyyx2.ui.activity;

import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;

import cn.edu.nhic.wyyx2.R;
import cn.edu.nhic.wyyx2.base.BaseFragment;
import cn.edu.nhic.wyyx2.ui.fragment.CarFragment;
import cn.edu.nhic.wyyx2.ui.fragment.DeserveFragment;
import cn.edu.nhic.wyyx2.ui.fragment.HomeFragment;
import cn.edu.nhic.wyyx2.ui.fragment.MineFragment;
import cn.edu.nhic.wyyx2.ui.fragment.SortFragment;
import cn.edu.nhic.wyyx2.utils.LogUtils;

public class MainActivity extends AppCompatActivity {

    public BottomNavigationView mBottomNavigationView;
    //public static final String TAG ="MainActivity" ;
    private HomeFragment mHomeFragment;
    private SortFragment mSortFragment;
    private MineFragment mMineFragment;
    private CarFragment mCarFragment;
    private DeserveFragment mDeserveFragment;
    private FragmentManager mSupportFragmentManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //initView();
        //ButterKnife.bind(this);
        initFragments();
        initListener();
    }

    private void initFragments() {
        mHomeFragment = new HomeFragment();
        mSortFragment = new SortFragment();
        mDeserveFragment = new DeserveFragment();
        mCarFragment = new CarFragment();
        mMineFragment = new MineFragment();
        mSupportFragmentManager = getSupportFragmentManager();
        switchFragment (mHomeFragment);
    }
    private void initListener() {
        mBottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {


            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                //Log.d(TAG,"TITLE"+item.getTitle()+"id"+item.getItemId());
                //log等级控制
                if(item.getItemId()==R.id.home){
                    LogUtils.d(MainActivity.class,"切换到首页");
                    switchFragment (mHomeFragment);

                }else if(item.getItemId()==R.id.shfl){
                    LogUtils.i(MainActivity.class,"切换到商品分类");
                    switchFragment (mSortFragment);

                }else if(item.getItemId()==R.id.deserve){
                    LogUtils.w(MainActivity.class,"切换到值得买");
                    switchFragment (mDeserveFragment);

                }else if(item.getItemId()==R.id.car){
                    LogUtils.e(MainActivity.class,"切换到购物车");
                    switchFragment (mCarFragment);

                }else if(item.getItemId()==R.id.mine){
                    LogUtils.v(MainActivity.class,"切换到我的");
                    switchFragment (mMineFragment);

                }
                return true;
            }
        });
       
    }

    private void switchFragment(BaseFragment targetFragment) {
        FragmentTransaction fragmentTransaction=mSupportFragmentManager.beginTransaction();
        fragmentTransaction.replace(R.id.main_page_container,targetFragment);
        fragmentTransaction.commit();//要习惯性的提交事务

    }
/*
    private void initView() {
        mBottomNavigationView = (BottomNavigationView) this.findViewById(R.id.main_navigation_bar);

        HomeFragment homeFragment=new HomeFragment();

        //依次把fragment添加进去

        FragmentManager fm=getSupportFragmentManager();
        FragmentTransaction transaction=fm.beginTransaction();
        transaction.add(R.id.main_page_container,homeFragment);
        transaction.commit();

    }
    */
}

04-24 00:42:11.585 5841-5841/? I/art: Not late-enabling -Xcheck:jni (already on)

04-24 00:42:11.586 5841-5841/? W/art: Unexpected CPU variant for X86 using defaults: x86

04-24 00:42:11.630 5841-5848/? E/art: Failed sending reply to debugger: Broken pipe

04-24 00:42:11.630 5841-5848/? I/art: Debugger is no longer active

04-24 00:42:11.631 5841-5848/? I/art: Starting a blocking GC Instrumentation

04-24 00:42:11.959 5841-5841/? W/System: ClassLoader referenced unknown path: /data/app/cn.edu.nhic.wyyx2-2/lib/x86

04-24 00:42:11.972 5841-5841/? I/InstantRun: starting instant run server: is main process

04-24 00:42:12.408 5841-5841/? W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable

04-24 00:42:13.112 5841-5841/cn.edu.nhic.wyyx2 D/AndroidRuntime: Shutting down VM

                                                                --------- beginning of crash

04-24 00:42:13.112 5841-5841/cn.edu.nhic.wyyx2 E/AndroidRuntime: FATAL EXCEPTION: main

                                                                Process: cn.edu.nhic.wyyx2, PID: 5841

                                                                java.lang.RuntimeException: Unable to start activity ComponentInfo{cn.edu.nhic.wyyx2/cn.edu.nhic.wyyx2.ui.activity.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.design.widget.BottomNavigationView.setOnNavigationItemSelectedListener(android.support.design.widget.BottomNavigationView$OnNavigationItemSelectedListener)' on a null object reference

                                                                    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)

                                                                    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)

                                                                    at android.app.ActivityThread.-wrap12(ActivityThread.java)

                                                                    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)

                                                                    at android.os.Handler.dispatchMessage(Handler.java:102)

                                                                    at android.os.Looper.loop(Looper.java:154)

                                                                    at android.app.ActivityThread.main(ActivityThread.java:6119)

                                                                    at java.lang.reflect.Method.invoke(Native Method)

                                                                    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)

                                                                    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

                                                                 Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.design.widget.BottomNavigationView.setOnNavigationItemSelectedListener(android.support.design.widget.BottomNavigationView$OnNavigationItemSelectedListener)' on a null object reference

                                                                    at cn.edu.nhic.wyyx2.ui.activity.MainActivity.initListener(MainActivity.java:51)

                                                                    at cn.edu.nhic.wyyx2.ui.activity.MainActivity.onCreate(MainActivity.java:38)

                                                                    at android.app.Activity.performCreate(Activity.java:6679)

                                                                    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)

                                                                    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)

                                                                    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 

                                                                    at android.app.ActivityThread.-wrap12(ActivityThread.java) 

                                                                    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 

                                                                    at android.os.Handler.dispatchMessage(Handler.java:102) 

                                                                    at android.os.Looper.loop(Looper.java:154) 

                                                                    at android.app.ActivityThread.main(ActivityThread.java:6119) 

                                                                    at java.lang.reflect.Method.invoke(Native Method) 

                                                                    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 

                                                                    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 

04-24 00:42:22.261 5841-5848/cn.edu.nhic.wyyx2 W/art: Suspending all threads took: 7.128ms

04-24 00:42:22.760 5841-5848/cn.edu.nhic.wyyx2 W/art: Suspending all threads took: 5.577ms

已解决，空时针问题