本文实例讲述了Android编程实现二级下拉菜单及快速搜索的方法。分享给大家供大家参考，具体如下：

一、我们要做什么？

上面有个搜索框，下面是一个二级下拉菜单。

输入查询内容，下面列表将显示查询结果。

二、界面设计

(1)这是主框架(部分属性已经省去，请看源码)，从上至下分别是文本框，列表，二级列表。

android:id="@+id/city_middle">

android:id="@+id/txtfind"

android:hint="请输入" >

android:id="@+id/listfind" >

android:id="@+id/exList" />

(2)一级菜单栏样式，图片将区别是否展开

android:id="@+id/group" >

android:id="@+id/tubiao">

(3)二级菜单栏样式

android:id="@+id/child">

三、代码设计

(1) 定义菜单对应数据

public static List fatherList = new ArrayList();

public static List> childList = new ArrayList>();

生成测试数据

for (int i = 0; i < 20; i++) {

fatherList.add(new BasicNameValuePair("father" + i, "father" + i));

List cList = new ArrayList();

for (int j = 0; j < 5; j++) {

cList.add(new BasicNameValuePair("child" + i + ":" + j, "child"

+ i + ":" + j));

}

childList.add(cList);

}

(2)定义列表适配器

protected class ListAdapter extends BaseAdapter {

private LayoutInflater mInflater;

//查询结果列表

private List list = new ArrayList();

public ListAdapter(Context context, String strin) {

mInflater = LayoutInflater.from(context);

//查询匹配

for (int i = 0; i < childList.size(); i++) {

for (int j = 0; j < childList.get(i).size(); j++) {

String tmp = childList.get(i).get(j).getValue();

if (tmp.indexOf(strin) >= 0) {

list.add(new BasicNameValuePair(childList.get(i).get(j)

.getName(), tmp));

}

}

}

}

public int getCount() {

return list.size();

}

public Object getItem(int position) {

return position;

}

public long getItemId(int position) {

return position;

}

public View getView(final int position, View convertView,

ViewGroup parent) {

convertView = mInflater.inflate(R.layout.child, null);

TextView title = (TextView) convertView.findViewById(R.id.child);

title.setText(list.get(position).getValue());

return convertView;

}

}

初始化列表，默认为隐藏

list = (ListView) findViewById(R.id.listfind);

list.setVisibility(View.GONE);

(3)定义二级列表适配器

protected class ExAdapter extends BaseExpandableListAdapter {

@Override

public int getGroupCount() {

return fatherList.size();

}

@Override

public int getChildrenCount(int groupPosition) {

return childList.get(groupPosition).size();

}

@Override

public Object getGroup(int groupPosition) {

return fatherList.get(groupPosition).getValue();

}

@Override

public Object getChild(int groupPosition, int childPosition) {

return childList.get(groupPosition).get(childPosition).getValue();

}

@Override

public long getGroupId(int groupPosition) {

return groupPosition;

}

@Override

public long getChildId(int groupPosition, int childPosition) {

return childPosition;

}

@Override

public View getGroupView(int groupPosition, boolean isExpanded,

View convertView, ViewGroup parent) {

View view = convertView;

if (view == null) {

LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

view = inflater.inflate(R.layout.group, null);

}

TextView t = (TextView) view.findViewById(R.id.group);

t.setText(fatherList.get(groupPosition).getValue());

//展开，改变图片

ImageView gImg = (ImageView) view.findViewById(R.id.tubiao);

if (isExpanded)

gImg.setBackgroundResource(R.drawable.mm_submenu_down_normal);

else

gImg.setBackgroundResource(R.drawable.mm_submenu_normal);

return view;

}

@Override

public View getChildView(int groupPosition, int childPosition,

boolean isLastChild, View convertView, ViewGroup parent) {

View view = convertView;

if (view == null) {

LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

view = inflater.inflate(R.layout.child, null);

}

TextView t = (TextView) view.findViewById(R.id.child);

t.setText(childList.get(groupPosition).get(childPosition)

.getValue());

return view;

}

@Override

public boolean hasStableIds() {

return true;

}

@Override

public boolean isChildSelectable(int groupPosition, int childPosition) {

return true;

}

}

初始化二级菜单

exList = (ExpandableListView) findViewById(R.id.exList);

exList.setAdapter(new ExAdapter());

exList.setGroupIndicator(null);

exList.setDivider(null);

(4)搜索事件，输入改变即触发

txtFind = (EditText) findViewById(R.id.txtfind);

txtFind.addTextChangedListener(new TextWatcher() {

@Override

public void beforeTextChanged(CharSequence s, int start, int count,

int after) {

}

@Override

public void onTextChanged(CharSequence s, int start, int before,

int count) {

}

@Override

public void afterTextChanged(Editable s) {

if (s != null && !s.toString().equals("")) {

list.setAdapter(new ListAdapter(DWinterDemoActivity.this, s

.toString()));

list.setVisibility(View.VISIBLE);

exList.setVisibility(View.GONE);

} else {

list.setVisibility(View.GONE);

exList.setVisibility(View.VISIBLE);

}

}

});

(5)去除焦点自动弹出输入

getWindow().setSoftInputMode(

WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN);

希望本文所述对大家Android程序设计有所帮助。