Android模仿美团顶部的滑动菜单实例代码

/** * Created by CZY on 2017/6/23. */public class Subject { //主题名 private String name; //主题图标资源ID private int icon; public Subject(String name, int icon) {  this.name = name;  this.icon = icon; } public String getName() {  return name; } public void setName(String name) {  this.name = name; } public int getIcon() {  return icon; } public void setIcon(int icon) {  this.icon = icon; }}

/** * Created by CZY on 2017/6/23. */public class GridViewAdapter extends BaseAdapter { private List<Subject> subjectList; private LayoutInflater layoutInflater; //当前页索引 private int currentIndex; //占满屏幕时每页展示的主题个数 private int pageSize; public GridViewAdapter(Context context, List<Subject> subjectList, int currentIndex, int pageSize) {  this.layoutInflater = LayoutInflater.from(context);  this.subjectList = subjectList;  this.currentIndex = currentIndex;  this.pageSize = pageSize; } /**  * 如果剩余数据能够完全占满当前页，则返回 pageSize  * 如果不能，则返回剩余的数据个数  */ @Override public int getCount() {  return subjectList.size() > (currentIndex + 1) * pageSize ? pageSize : (subjectList.size() - currentIndex * pageSize); } /**  * 计算出正确的索引  */ @Override public Object getItem(int position) {  return subjectList.get(position + currentIndex * pageSize); } @Override public long getItemId(int position) {  return position + currentIndex * pageSize; } @Override public View getView(int position, View convertView, ViewGroup parent) {  ViewHolder viewHolder;  if (convertView == null) {   convertView = layoutInflater.inflate(R.layout.item_grid_view, parent, false);   viewHolder = new ViewHolder();   viewHolder.tv_subject = (TextView) convertView.findViewById(R.id.tv_subject);   viewHolder.iv_subject = (ImageView) convertView.findViewById(R.id.iv_subject);   convertView.setTag(viewHolder);  } else {   viewHolder = (ViewHolder) convertView.getTag();  }  int pos = position + currentIndex * pageSize;  viewHolder.tv_subject.setText(subjectList.get(pos).getName());  viewHolder.iv_subject.setImageResource(subjectList.get(pos).getIcon());  return convertView; } private class ViewHolder {  private TextView tv_subject;  private ImageView iv_subject; }}

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="wrap_content" android:paddingBottom="10dp" android:paddingTop="10dp"> <ImageView  android:id="@+id/iv_subject"  android:layout_width="40dp"  android:layout_height="40dp"  android:layout_centerHorizontal="true" /> <TextView  android:id="@+id/tv_subject"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:layout_below="@id/iv_subject"  android:layout_centerHorizontal="true"  android:layout_marginTop="3dp"  android:textSize="12sp" /></RelativeLayout>

/** * Created by CZY on 2017/6/23. */public class ViewPagerAdapter extends PagerAdapter { private List<View> viewList; public ViewPagerAdapter(List<View> viewList) {  this.viewList = viewList; } @Override public void destroyItem(ViewGroup container, int position, Object object) {  container.removeView(viewList.get(position)); } @Override public Object instantiateItem(ViewGroup container, int position) {  container.addView(viewList.get(position));  return (viewList.get(position)); } @Override public int getCount() {  return viewList == null ? 0 : viewList.size(); } @Override public boolean isViewFromObject(View view, Object object) {  return view == object; }}

public class MainActivity extends AppCompatActivity { private String[] titles = {"美食", "电影", "酒店住宿", "休闲娱乐", "甜品饮品",   "水上乐园", "汽车服务", "美发", "丽人", "景点",   "足疗按摩", "运动健身", "健身", "超市", "买菜",   "今日新单", "外卖", "自助餐", "KTV", "机票/火车票",   "周边游", "小吃快餐", "面膜", "美甲美睫", "火锅",   "生日蛋糕", "母婴亲子", "生活服务", "婚纱摄影", "学习培训",   "家装", "结婚"}; private List<Subject> subjectList; private LinearLayout ll_dot; //每页展示的主题个数 private final int pageSize = 10; //当前页索引 private int currentIndex; @Override protected void onCreate(Bundle savedInstanceState) {  super.onCreate(savedInstanceState);  setContentView(R.layout.activity_main);  ViewPager viewPager = (ViewPager) findViewById(R.id.viewPager);  ll_dot = (LinearLayout) findViewById(R.id.ll_dot);  subjectList = new ArrayList<>();  for (String title : titles) {   subjectList.add(new Subject(title, R.drawable.icon));  }  //需要的页面数  int pageCount = (int) Math.ceil(subjectList.size() * 1.0 / pageSize);  List<View> viewList = new ArrayList<>();  for (int i = 0; i < pageCount; i++) {   GridView gridView = (GridView) getLayoutInflater().inflate(R.layout.layout_grid_view, viewPager, false);   gridView.setAdapter(new GridViewAdapter(this, subjectList, i, pageSize));   viewList.add(gridView);   gridView.setOnItemClickListener(new AdapterView.OnItemClickListener() {    @Override    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {     int pos = position + currentIndex * pageSize;     Toast.makeText(MainActivity.this, subjectList.get(pos).getName(), Toast.LENGTH_SHORT).show();    }   });  }  viewPager.setAdapter(new ViewPagerAdapter(viewList));  for (int i = 0; i < pageCount; i++) {   ll_dot.addView(getLayoutInflater().inflate(R.layout.view_dot, null));  }  //使第一个小圆点呈选中状态  ll_dot.getChildAt(0).findViewById(R.id.v_dot).setBackgroundResource(R.drawable.dot_selected);  viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {   public void onPageSelected(int position) {    ll_dot.getChildAt(currentIndex).findViewById(R.id.v_dot).setBackgroundResource(R.drawable.dot_normal);    ll_dot.getChildAt(position).findViewById(R.id.v_dot).setBackgroundResource(R.drawable.dot_selected);    currentIndex = position;   }   public void onPageScrolled(int arg0, float arg1, int arg2) {   }   public void onPageScrollStateChanged(int arg0) {   }  }); }}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="wrap_content" android:layout_height="wrap_content"> <View  android:id="@+id/v_dot"  android:layout_width="8dp"  android:layout_height="8dp"  android:layout_marginLeft="2dp"  android:layout_marginRight="2dp"  android:background="@drawable/dot_normal" /></RelativeLayout>