ListView與RadioButton組合——自定義單選列表
阿新 • • 發佈:2019-01-28
Android自帶的RadioButton單選框只支援新增文字,我們自己寫Adapter實現自定義的RadioButton
首先item的XML原始碼
search_user_item.xml (現在只是文字+單選按鈕+自定義背景,可以根據需要隨意擴充套件)
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/search_user_list_item" android:layout_width="fill_parent" android:layout_height="30dp" android:layout_marginBottom="10dp" android:layout_marginTop="10dp" android:background="@drawable/more_item_press" android:gravity="center_vertical" android:orientation="horizontal" > <TextView android:id="@+id/search_user_name" android:layout_width="200dp" android:layout_height="wrap_content" android:layout_marginLeft="30dp" android:gravity="left" android:textColor="@android:color/black" android:textSize="16sp" /> <RadioButton android:id="@+id/radio_btn" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="10dp" /> </LinearLayout>
Listview就是用系統自帶的
<ListView android:id="@+id/search_user_list" android:layout_width="fill_parent" android:layout_height="200dp" android:layout_marginLeft="5dp" android:layout_marginRight="5dp" android:paddingBottom="5dp" android:cacheColorHint="@android:color/transparent" android:divider="@null" android:listSelector="@android:color/transparent" android:visibility="gone" > </ListView>
再來是Adapter程式碼
SearchUserAdapter.java (具體改動寫在程式碼註釋裡面)
package ouc.sei.suxin.android.ui.adapter; import java.util.HashMap; import java.util.List; import ouc.sei.suxin.R; import android.content.Context; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.LinearLayout; import android.widget.RadioButton; import android.widget.TextView; public class SearchUserAdapter extends BaseAdapter { private Context context; private List<String> userList; HashMap<String,Boolean> states=new HashMap<String,Boolean>();//用於記錄每個RadioButton的狀態,並保證只可選一個
public SearchUserAdapter(Context context, List<String> userList)
{
this.context = context;
this.userList= userList;
}
@Override
public int getCount() {
return userList.size();
}
@Override
public Object getItem(int position) {
return userList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ViewHolder holder;
if (convertView == null) {
convertView = LayoutInflater.from(context).inflate(R.layout.search_user_item, null);
holder = new ViewHolder();
holder.background = (LinearLayout) convertView.findViewById(R.id.search_user_list_item);
holder.userName = (TextView) convertView.findViewById(R.id.search_user_name);
convertView.setTag(holder);
}else{
holder=(ViewHolder) convertView.getTag();
}
final RadioButton radio=(RadioButton) convertView.findViewById(R.id.radio_btn);
holder.rdBtn = radio;
holder.userName.setText(userList.get(position));
//根據Item位置分配不同背景
if(userList.size() > 0)
{
if(userList.size() == 1)
{
holder.background.setBackgroundResource(R.drawable.more_item_press);
}
else{
if(position == 0){
holder.background.setBackgroundResource(R.drawable.more_itemtop_press);
}
else if(position == userList.size()-1){
holder.background.setBackgroundResource(R.drawable.more_itembottom_press);
}
else{
holder.background.setBackgroundResource(R.drawable.more_itemmiddle_press);
}
}
}
//當RadioButton被選中時,將其狀態記錄進States中,並更新其他RadioButton的狀態使它們不被選中
holder.rdBtn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
//重置,確保最多隻有一項被選中
for(String key:states.keySet()){
states.put(key, false);
}
states.put(String.valueOf(position), radio.isChecked());
SearchUserAdapter.this.notifyDataSetChanged();
}
});
boolean res=false;
if(states.get(String.valueOf(position)) == null || states.get(String.valueOf(position))== false){
res=false;
states.put(String.valueOf(position), false);
}
else
res = true;
holder.rdBtn.setChecked(res);
return convertView;
}
static class ViewHolder {
LinearLayout background;
TextView userName;
RadioButton rdBtn;
}
}
List適配程式碼(與一般無異):
adapter = new SearchUserAdapter(this, searchUserList);
searchUserLV.setAdapter(adapter);
searchUserLV.setVisibility(View.VISIBLE);
setListViewHeightBasedOnChildren(searchUserLV);
這裡還根據內容動態設定了一下,具體函式如下:
public void setListViewHeightBasedOnChildren(ListView listView) {
Adapter listAdapter = listView.getAdapter();
if (listAdapter == null) {
return;
}
int totalHeight = 0;
int viewCount = listAdapter.getCount();
for (int i = 0; i < viewCount; i++) {
View listItem = listAdapter.getView(i, null, listView);
listItem.measure(0, 0);
totalHeight += listItem.getMeasuredHeight();
}
ViewGroup.LayoutParams params = listView.getLayoutParams();
params.height = totalHeight
+ (listView.getDividerHeight() * (listAdapter.getCount()-1)) + 10;//加10是為了適配自定義背景
listView.setLayoutParams(params);
}
當需要獲取ListView中RadioButton的選擇狀態時,可以直接看Adapter中的states,具體如下:
// 根據RadioButton的選擇情況確定使用者名稱
for (int i = 0, j = searchUserLV.getCount(); i < j; i++) {
View child = searchUserLV.getChildAt(i);
RadioButton rdoBtn = (RadioButton) child
.findViewById(R.id.radio_btn);
if (rdoBtn.isChecked())
searchUser = searchUserList.get(i);
}
這裡的searchUserList是呼叫後臺服務獲取的使用者名稱列表,通過states獲取選中使用者名稱進行後續操作
效果圖: