前言
本文主要给大家介绍了关于Android模仿美团顶部滑动菜单的相关内容，分享出来供大家参考学习，下面话不多说了，来一起看看详细的介绍吧。
先来看下效果图：
实现方法
这是通过 ViewPager 和 GridView 相结合做出来的效果，每一个 ViewPager 页面都是一个 GridView，底部的每个滑动指示圆点都是从布局文件中 inflate 出来的
首先需要一个代表每个活动主题的 JavaBean
/** * 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; } }
然后用一个 List< Subject > 来承载需要显示的所有主题内容，将这些数据传给 GridViewAdapter 。因为 ViewPager 有几个页面就有几个GridView ，每个GridView对应的是哪些数据都需要在其内部根据页面索引进行计算
/** * 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; } }
需要使用到的布局文件 item_grid_view 如下所示
<?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>
使用到了 ViewPager，自然也需要一个 ViewPagerAdapter
/** * 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; } }
在 MainActivity 中进行数据填充
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) { } }); } }
每一个小圆点都对应一个布局文件，其中只包含一个View，重点是设置是设备其 background 属性，使其呈现圆形
<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>
代码整体来说都挺简单的，这里也提供源代码下载：仿美团顶部滑动菜单
总结
以上就是这篇文章的全部内容了，希望本文的内容对各位Android开发者们的学习或者工作能带来一定的帮助，如果有疑问大家可以留言交流，谢谢大家对脚本之家的支持。