Android ListView and BaseAdapter applications, androidbaseadapter

Android ListView and BaseAdapter applications, androidbaseadapter

Steps:

1. Create a ListView object. -- (function: bind an Adapter to present data)

2. Create an Item column. xml layout for ListView; -- (Role: implement the column layout for ListView)

3. Create a View data instance (class) for Item. xml; -- (Role: implement the Item column data interface)

4. inherit BaseAdapter to create a MyAdapter class; -- (function: encapsulate ListView's. xml layout and Item data)

5. Of course, more operations are required. Here is a simple method;

Adapter implementation:

1 private class UpdateAdpter extends BaseAdapter {2 3 private LayoutInflater mInflater; 4 private List <ItemData> mItemsData; 5 6 public UpdateAdpter (Context context, List <ItemData> listItemData) {7 this. mInflater = LayoutInflater. from (context); 8 this. mItemsData = listItemData; 9 10} 11 12 @ Override 13 public int getCount () {14 // TODO Auto-generated method stub 15 return mItemsData. size (); 16} 17 18 @ Override 19 public Object getItem (int position) {20 // TODO Auto-generated method stub 21 return mItemsData. get (position); 22} 23 24 @ Override 25 public long getItemId (int position) {26 // TODO Auto-generated method stub 27 return position; 28} 29 30 @ Override 31 public View getView (final int position, View convertView, 32 ViewGroup parent) {33 // TODO Auto-generated method stub 34 ViewHolder holder; 35 if (convertView = null) {36 convertView = mInflater. inflate (37 R. layout. activity_account_update_listview_item, null); 38 holder = new ViewHolder (convertView); 39 convertView. setTag (holder); 40 41} else {42 holder = (ViewHolder) convertView. getTag (); 43} 44 ItemData item = mItemsData. get (position); 45 holder. title. setText (item. getTitle (); 46 holder. price. setText (item. getPrice (); 47 holder. text. setText (item. getBuyText (); 48 holder. status. setText (item. getStatus (); 49 50 return convertView; 51} 52 53 public class ViewHolder {54 public TextView title; 55 public TextView price; 56 public TextView buytext; 57 public TextView status; 58 59 ViewHolder (View view) {60 title = (TextView) view 61. findViewById (R. id. TV _accountupdateitem_title); 62 price = (TextView) view 63. findViewById (R. id. TV _accountupdateitem_price); 64 text = (TextView) view 65. findViewById (R. id. TV _accountupdateitem_buytext); 66 status = (TextView) view. findViewById (R. id. TV _accountupdate_status); 67} 68} 69} 70 71 private class ItemData {72 private String title; // title 73 private String price; // price 74 private String text; // content 75 private String status; // status 76 77 public void setTitle (String value) {78 title = value; 79} 80 81 public String getTitle () {82 return title; 83} 84 85 public void setPrice (String value) {86 price = value; 87} 88 89 public String getPrice () {90 return price; 91} 92 93 public void setText (String value) {94 buytext = value; 95} 96 97 public String getText () {98 return buytext; 99} 100 101 public void setStatus (String value) {102 status = value; 103} 104 105 public String getStatus () {106 return status; 107} 108}

Activity has an instance:

Public class UpdateActivity extends Activity implements OnClickListener {private ListView UpdateLView; @ Override protected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. activity_account_update); iniView ();} public void iniView () {UpdateLView = (ListView) findViewById (R. id. account_update_listView); iniListViewDataUpdate (); // initial listview data} @ Override public void onClick (View v) {// TODO Auto-generated method stub} private void iniListViewDataUpdate () {ItemData itemData; List <ItemData> listItemData = new ArrayList <ItemData> (); for (int I = 0; I <2; I ++) {itemData = new ItemData (); itemData. setTitle ("title"); itemData. setPrice ("price"); itemData. setText ("text"); itemData. setStatus ("status"); listItemData. add (itemData);} nowUpdateLView. setAdapter (new UpdateAdpter (this, listItemData ));}

Item. xml;

<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="wrap_content"    android:background="@android:color/white"    android:descendantFocusability="blocksDescendants"    android:gravity="center_vertical" >    <LinearLayout        android:id="@+id/lyt_roomlistview_item"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="vertical" >        <LinearLayout            android:layout_width="match_parent"            android:layout_height="40dp"            android:layout_marginLeft="8dp"            android:layout_marginRight="8dp"            android:background="@android:color/white" >            <TextView                android:id="@+id/tv_accountupdateitem_title"                android:layout_width="wrap_content"                android:layout_height="match_parent"                android:gravity="center"                android:text="title"                android:textSize="18sp" />            <TextView                android:id="@+id/tv_accountupdate_status"                android:layout_width="wrap_content"                android:layout_height="match_parent"                android:layout_marginLeft="12dp"                android:layout_weight="1"                android:gravity="left|center"                android:text="button"                android:textColor="@android:color/holo_orange_dark"                android:textSize="16sp" />            <TextView                android:id="@+id/tv_accountupdateitem_price"                android:layout_width="wrap_content"                android:layout_height="match_parent"                android:gravity="center"                android:text="price"                android:textColor="@android:color/holo_orange_dark"                android:textSize="16sp" />        </LinearLayout>        <LinearLayout            android:layout_width="match_parent"            android:layout_height="40dp"            android:layout_marginLeft="8dp"            android:layout_marginRight="8dp"            android:background="@android:color/white" >            <TextView                android:id="@+id/tv_accountupdateitem_buytext"                android:layout_width="wrap_content"                android:layout_height="match_parent"                android:layout_weight="1"                android:gravity="center_vertical"                android:text="Textview"                android:textSize="16sp" />            <TextView                android:id="@+id/textView2"                android:layout_width="50dp"                android:layout_height="30dp"                android:layout_gravity="center"                android:background="@android:color/holo_orange_dark"                android:gravity="center"                android:text="@string/title_buy"                android:textColor="@android:color/white"                android:textSize="16sp" />        </LinearLayout>    </LinearLayout></RelativeLayout>

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