Android适配器学习和使用

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Android的适配器的学习和使用(整理)在开发中我们需要绑定一些数据展现到桌面上,这是就需要AdapterView。

AdapterView是ViewGroup的子类,它决定了怎么展现视图通过Adapter来绑定特殊的数据类型。

AdapterView是非常有帮助的当你展现数据在你的布局中。

Gallery,ListView和Spinner是AdapterView的子类。

下面看一下AdapterView的结构图:然后再看一下Adapter的结构图:上面已经充分展现了他们的子类和父类的基础关系。

下面我们看一个ListViewDemo的例子:先来看一个简单的adapter的例子:public class SimpleList extends ListActivity {private String[] mListString={"姓名:王魁锋","性别:男","年龄:23", "居住地:上海市普陀区","邮箱:wangkuifeng0118@"};private ListView mListView=null;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);mListView=this.getListView();setListAdapter(new ArrayAdapter<String>(this,yout.simple_list_item_1,mListString));mListView.setOnItemClickListener(new OnItemClickListener() {@Overridepublic void onItemClick(AdapterView<?> parent, View view, int position, long id) {// TODO Auto-generated method stubToast.makeText(SimpleList.this, "你选择了:"+mListString[position], 1).show();}});}这里用到了系统定义好的适配模式,当然这只能用来简单的数据适配,下面看一下效果:接下来看一个稍微复杂点的,SimpleAdapter怎么适配:public class IconList extends ListActivity {private String[] mListTitle = { "姓名", "性别", "年龄", "居住地","邮箱"};private String[] mListStr = { "王魁锋", "男", "23", "上海市普陀区","wangkuifeng0118@"};ListView mListView = null;ArrayList<Map<String,Object>> mData= newArrayList<Map<String,Object>>();;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubmListView = getListView();int lengh = mListTitle.length;for(int i =0; i < lengh; i++) {Map<String,Object> item = new HashMap<String,Object>(); item.put("image", R.drawable.portrait);item.put("title", mListTitle[i]);item.put("text", mListStr[i]);mData.add(item);}SimpleAdapter adapter = newSimpleAdapter(this,mData,yout.iconlist,new String[]{"image","title","text"},newint[]{R.id.image,R.id.title,R.id.text});setListAdapter(adapter);mListView.setOnItemClickListener(new OnItemClickListener() {@Overridepublic void onItemClick(AdapterView<?> parent, View view,int position, long id) {// TODO Auto-generated method stubToast.makeText(IconList.this,"您选择了标题:" + mListTitle[position] + " 内容:"+mListStr[position],Toast.LENGTH_LONG).show();}});super.onCreate(savedInstanceState);}}上面的数据可以是同数据库读取的也可以是从网络获取的,这里不做过多介绍,看下效果:哈哈看起来美观了些,如果要做更复杂的布局,哪就要用BaseAdapter了。

先看一下布局文件:<?xml version="1.0" encoding="utf-8"?><RelativeLayoutxmlns:android="/apk/res/android" android:layout_width="fill_parent"android:layout_height="wrap_content"><ImageView android:id="@+id/color_image"android:layout_width="wrap_content"android:layout_height="fill_parent"android:layout_alignParentTop="true"android:layout_alignParentBottom="true"android:adjustViewBounds="true"android:padding="2dip" /><TextView android:id="@+id/color_title"android:layout_width="fill_parent"android:layout_height="wrap_content"android:layout_toRightOf="@+id/color_image"android:layout_alignParentTop="true"android:layout_alignParentRight="true"android:singleLine="true"android:ellipsize="marquee"android:textSize="15dip" /><TextView android:id="@+id/color_text"android:layout_width="fill_parent"android:layout_height="wrap_content"android:layout_toRightOf="@+id/color_image"android:layout_below="@+id/color_title"android:layout_alignParentBottom="true"android:layout_alignParentRight="true"android:singleLine="true"android:ellipsize="marquee"android:textSize="20dip" /></RelativeLayout>下面是核心代码:public class ColorList extends ListActivity {private String[] mListTitle = { "姓名", "性别", "年龄", "居住地","邮箱"};private String[] mListText={"王魁锋","男","23","上海市普陀区","wangkuifeng0118@"};private ListView mListView=null;private MyListAdapter myAdapter=null;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubmListView=this.getListView();myAdapter=new MyListAdapter(this);this.setListAdapter(myAdapter);mListView.setOnItemClickListener(new OnItemClickListener() {@Overridepublic void onItemClick(AdapterView<?> parent, View view, int position, long id) {// TODO Auto-generated method stubView v=parent.getChildAt(position);v.setBackgroundColor(Color.RED);Toast.makeText(ColorList.this, "你选择了"+mListText[position], 1).show();}});super.onCreate(savedInstanceState);}private class MyListAdapter extends BaseAdapter{private Context mContext;private int[] colors=new int[]{0xff626569,0xff4f5257 };public MyListAdapter(Context context){mContext=context;}@Overridepublic int getCount() {// TODO Auto-generated method stubreturn mListText.length;}@Overridepublic Object getItem(int position) {// TODO Auto-generated method stubreturn position;}@Overridepublic long getItemId(int position) {// TODO Auto-generated method stubreturn position;}@Overridepublic View getView(int position, View convertView, ViewGroup parent) {ImageView image=null;TextView title=null;TextView content=null;if(convertView==null){convertView=LayoutInflater.from(mContext).inflate(yo ut.colorlist, null);image=(ImageView)convertView.findViewById(R.id.color_image);title=(TextView)convertView.findViewById(R.id.color_title);content=(TextView)convertView.findViewById(R.id.color_text);}int colorPos=position%colors.length;convertView.setBackgroundColor(colors[colorPos]);title.setText(mListTitle[position]);content.setText(mListText[position]);image.setImageResource(R.drawable.portrait);return convertView;}}}BaseAdapter可以让我们做比较复杂的布局,只要在xml文件中设置好布局格式,在getView中分别取出放入相应的值就可以了。