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：
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
/**
* 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,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，谢谢大家对编程小技巧的支持。
