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。
