ViewPager 实现左右滑动 点击Tab

效果图

1. 创建top.xml、bottom.xml。在bottom.xml中放置四个ImageButton 使用的是LinerLayout 在这里可以设置android:layout_weight=”1” 使 四个店家按钮平均分配所占大小
2. 取消activity的titlebar 在setContentView(R.layout.activity_main);之前调用requestWindowFeature(Window.FEATURE_NO_TITLE); 无效。最后在application.xml中设置android:theme=”@style/Theme.AppCompat.NoActionBar”。(这里犯2 写道activity_main.xml中了 )

3. ViewPager步骤：实例化PagerView，创建PagerAdapter 重写方法
   `pagerAdapter=new PagerAdapter() {

       @Override
       public void destroyItem(ViewGroup container, int position, Object object) {
           View view = mViews.get(position);
           container.removeView(view);
       }
       @Override
       public Object instantiateItem(ViewGroup container, int position) {
           View view = mViews.get(position);
           container.addView(view);
           return view;
       }
       @Override
       public int getCount() {
           return mViews.size();
       }
       @Override
       public boolean isViewFromObject(View view, Object object) {
           return view==object;
       }
   };`
   

4. 在点击切换按钮图片的时候 犯2 应设置：weixin_img.setImageResource(R.drawable.tab_weixin_pressed); 而非setBackgroundResource。
5. ViewPager 滑动事件监听

mViewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
                Log.d("InitEvent", "onPageScrolled() called with: " + "position = [" + position + "], positionOffset = [" + positionOffset + "], positionOffsetPixels = [" + positionOffsetPixels + "]");
            }

            @Override
            public void onPageSelected(int position) {
                //mViewPager.setCurrentItem(position);
                Log.d("InitEvent", "onPageSelected() called with: " + "position = [" + position + "]");
                resetImageBtn();
                switch (position){
                    case 0:
                    weixin_img.setImageResource(R.drawable.tab_weixin_pressed);
                        break;
                    case 1:
                    friend_img.setImageResource(R.drawable.tab_find_frd_pressed);
                        break;
                    case 2:
                    address_img.setImageResource(R.drawable.tab_address_pressed);
                        break;
                    case 3:
                    setting_img.setImageResource(R.drawable.tab_settings_pressed);
                        break;
                }
            }
            @Override
            public void onPageScrollStateChanged(int state) {
                Log.d("InitEvent", "onPageScrollStateChanged() called with: " + "state = [" + state + "]");
            }
        });

总结：在使用LinerLayout时 可以使用layout_weight 来设置所占比例 比较方便。

"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:background="#0000"
    android:orientation="vertical">
    "@layout/top"/>
    .support.v4.view.ViewPager
        android:id="@+id/viewpager"
        android:layout_width="match_parent"
        android:layout_weight="1"
        android:layout_height="0dp">
    .support.v4.view.ViewPager>

    "@layout/bottom" />