標籤:android 部落格 控制項 radiobutton listview
許久沒有寫過部落格了,近來在做Android開發,突然想到這裡,以後可以在這裡貼些代碼,做些記錄,與大家分享交流。Android開發中,常常會用到RadioButton與ListView的混合使用,使用者點擊一條Item,然後記錄下選中的狀態,其中最重要的是記錄好使用者點擊選中Item的位置。
布局檔案很簡單:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_marginLeft="10dp" android:layout_marginRight="10dp" android:orientation="vertical" > <TextView android:layout_width="match_parent" android:layout_height="wrap_content" android:gravity="center" android:text="@string/select_authors" android:textSize="25sp" /> <ListView android:id="@+id/list" android:layout_width="match_parent" android:layout_height="match_parent" android:scrollbars="none" /></LinearLayout>
ItemList也不複雜:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent"> <TextView android:id="@+id/author" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentLeft="true" android:layout_centerVertical="true" android:text="@string/author_name" android:textSize="20sp"/> <RadioButton android:id="@+id/radio" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignParentRight="true" android:layout_centerVertical="true"/></RelativeLayout>
RadioButtonList 類,這裡我寫了一些自己喜歡的作家(當然我也很喜歡和大家交流一些文學作品)作為類比資料。
package com.example.radiobuttonlisttest;import android.app.Activity;import android.os.Bundle;import android.widget.ListView;public class RadioButtonList extends Activity {private ListView radioButtonList;private RadioAdapter adapter;// 類比幾個資料,作為List的條目private String[] authors = { "芥川龍之介", "三島由紀夫", "川端康成", "村上春樹", "東野圭吾","張愛玲", "金庸", "錢鐘書", "老舍", "梁實秋", "亨利米勒", "海明威", "菲茲傑拉德", "凱魯亞克","傑克倫敦", "小仲馬", "杜拉斯", "福樓拜", "雨果", "巴爾紮克", "莎士比亞", "勞倫斯", "毛姆","柯南道爾", "笛福" };@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_radio_button_list);radioButtonList = (ListView) findViewById(R.id.list);adapter = new RadioAdapter(this, authors);radioButtonList.setAdapter(adapter);}}
適配器是最關鍵的,標記好選擇的位置,選中狀態不會因為ListView的滑動而出現混亂:
package com.example.radiobuttonlisttest;import android.content.Context;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.CompoundButton;import android.widget.CompoundButton.OnCheckedChangeListener;import android.widget.RadioButton;import android.widget.TextView;import android.widget.Toast;public class RadioAdapter extends BaseAdapter {private LayoutInflater inflater;private String[] authors;private viewHolder holder;// 標記使用者當前選擇的那一個作家private int index = -1;private Context c;public RadioAdapter(Context c, String[] authors) {super();this.c = c;this.authors = authors;inflater = LayoutInflater.from(c);}@Overridepublic int getCount() {return authors.length;}@Overridepublic Object getItem(int position) {return null;}@Overridepublic long getItemId(int position) {return 0;}@Overridepublic View getView(final int position, View convertView, ViewGroup parent) {holder = new viewHolder();if (convertView == null) {convertView = inflater.inflate(R.layout.item_list, null);holder.nameTxt = (TextView) convertView.findViewById(R.id.author);holder.selectBtn = (RadioButton) convertView.findViewById(R.id.radio);convertView.setTag(holder);} else {holder = (viewHolder) convertView.getTag();}holder.nameTxt.setText(authors[position]);holder.selectBtn.setOnCheckedChangeListener(new OnCheckedChangeListener() {@Overridepublic void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {if (isChecked) {Toast.makeText(c, "您選擇的作家是:" + authors[position],Toast.LENGTH_LONG).show();index = position;notifyDataSetChanged();}}});if (index == position) {// 選中的條目和當前的條目是否相等holder.selectBtn.setChecked(true);} else {holder.selectBtn.setChecked(false);}return convertView;}public class viewHolder {public TextView nameTxt;public RadioButton selectBtn;}}
最後看看:
650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/4D/9A/wKioL1RUmYHzGp8wAAHUsdUIf08328.jpg" style="float:none;" title="001v7yLagy6NeaQrZzzb9&690.jpg" alt="wKioL1RUmYHzGp8wAAHUsdUIf08328.jpg" />
650) this.width=650;" src="http://s3.51cto.com/wyfs02/M02/4D/9A/wKiom1RUmSXi98iQAAIRDufO4-I942.jpg" style="float:none;" title="001v7yLagy6NeaQwIZy98&690.jpg" alt="wKiom1RUmSXi98iQAAIRDufO4-I942.jpg" />
Android RadioButton與ListView的混合使用