Android實現二級下拉菜單及快速搜索功能示例

 一、我們要做什麼？

 上面有個搜索框，下面是一個二級下拉菜單。

 輸入查詢內容，下面列表將顯示查詢結果。

二、界面設計

（1）這是主框架（部分屬性已經省去，請看源碼），從上至下分別是文本框，列表，二級列表。

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout> 
    <LinearLayout 
        android:id="@+id/city_middle"> 
 
        <EditText 
            android:id="@+id/txtfind" 
            android:hint="請輸入" > 
        </EditText> 
 
        <ListView 
            android:id="@+id/listfind" > 
        </ListView> 
 
        <ExpandableListView 
            android:id="@+id/exList" /> 
    </LinearLayout> 
 
</LinearLayout> 

（2）一級菜單欄樣式，圖片將區別是否展開

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout  > 
 
    <TextView 
        android:id="@+id/group" > 
    </TextView> 
 
    <ImageView 
        android:id="@+id/tubiao"> 
    </ImageView> 
 
</LinearLayout> 

（3）二級菜單欄樣式

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout > 
 
    <TextView 
        android:id="@+id/child"> 
    </TextView> 
 
</LinearLayout> 

三、代碼設計

（1） 定義菜單對應數據

public static List<BasicNameValuePair> fatherList = new ArrayList<BasicNameValuePair>(); 
public static List<List<BasicNameValuePair>> childList = new ArrayList<List<BasicNameValuePair>>(); 

生成測試數據

for (int i = 0; i < 20; i++) { 
            fatherList.add(new BasicNameValuePair("father" + i, "father" + i)); 
            List<BasicNameValuePair> cList = new ArrayList<BasicNameValuePair>(); 
            for (int j = 0; j < 5; j++) { 
                cList.add(new BasicNameValuePair("child" + i + ":" + j, "child" 
                        + i + ":" + j)); 
            } 
            childList.add(cList); 
        } 

（2）定義列表適配器

protected class ListAdapter extends BaseAdapter { 
        private LayoutInflater mInflater; 
        //查詢結果列表 
        private List<BasicNameValuePair> list = new ArrayList<BasicNameValuePair>(); 
 
        public ListAdapter(Context context, String strin) { 
            mInflater = LayoutInflater.from(context); 
            //查詢匹配 
            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，默認為隱藏

list = (ListView) findViewById(R.id.listfind); 
list.setVisibility(View.GONE); 

（3）定義二級列表適配器

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()); 
            //展開，改變圖片 
            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; 
        } 
    } 

初始化二級菜單

exList = (ExpandableListView) findViewById(R.id.exList); 
exList.setAdapter(new ExAdapter()); 
exList.setGroupIndicator(null); 
exList.setDivider(null); 

（4）搜索事件，輸入改變即觸發

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）去除焦點自動彈出輸入

getWindow().setSoftInputMode( 
        WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_HIDDEN); 

源碼地址：http://115.com/file/c2r9e8ib#DWinterDemo.zip