Commonly used Android components: ListView and androidlistview

Commonly used Android components: ListView and androidlistview

Use ListAdapter as the ListView adapter.

Use the ListView. setAdapter () method to set the ListView adapter.

Adapter =NewArrayAdapter <String> (This, Android. R. layout.Simple_list_item_1); Adapter. add ("hello "); Adapter. add ("eoe "); Lv. setAdapter (adapter );

Android in front of R indicates that resources provided by the system are used.

Create an XML file under the layout package with the following content:

<? Xmlversion ="1.0"Encoding ="UTF-8"?> <ListViewxmlns: android =Http://schemas.android.com/apk/res/android" Android: layout_width ="Match_parent" Android: layout_height ="Match_parent"> </ListView>

Create an Adapter as follows:

Adapter =NewArrayAdapter <String> (This, R. layout.List_cell_view); Adapter. add ("hello "); Adapter. add ("eoe "); Lv. setAdapter (adapter );

PrivateBaseAdapter adapter =NewBaseAdapter (){ PrivateString [] data = {"user1", "user2", "user3", "user4", "user5", "user6 ", "User7", "user8", "user9", "user10", "user11", "user12", "user13", "user14 ",}; @ Override PublicView getView (IntPosition, View convertView, ViewGroup parent ){ TextView TV =NewTextView (MainActivity.This); TV. setText (getItem (position )); ReturnTV; } @ Override PublicLongGetItemId (IntPosition ){ ReturnPosition; } @ Override PublicString getItem (IntPosition ){ ReturnData [position]; } @ Override PublicIntGetCount (){ ReturnData. length; } };

The number of list items displayed on the interface when the program is running. The getView method is how many times the program is executed.

The View in the getView parameter indicates the View that is recycled by the system.

Optimization:

TextView TV =Null; If(ConvertView! =Null){ TV = (TextView) convertView; }Else{ TV =NewTextView (MainActivity.This); } TV. setText (getItem (position ));

Create a new Linearlayout layout file in layout:

<? Xmlversion ="1.0"Encoding ="UTF-8"?> <LinearLayoutxmlns: android =Http://schemas.android.com/apk/res/android" Android: layout_width ="Match_parent" Android: layout_height ="Match_parent" Android: orientation ="Horizontal"> <ImageView Android: layout_width ="120dp" Android: layout_height ="120dp" Android: id ="@ + Id/icon"/> <LinearLayout Android: layout_weight ="1" Android: layout_width ="0dp" Android: layout_height ="Match_parent" Android: orientation ="Vertical"> <TextView Android: id ="@ + Id/name" Android: layout_width ="Wrap_content" Android: layout_height ="Wrap_content"/> <TextView Android: id ="@ + Id/dec" Android: layout_width ="Wrap_content" Android: layout_height ="Wrap_content"/> </LinearLayout>   </LinearLayout>

Create an Adapter:

PrivateBaseAdapter adapter =NewBaseAdapter (){ PrivateListCellData [] data =NewListCellData [] { NewListCellData ("James", "male", android. R. drawable.Ic_btn_speak_now), NewListCellData ("Lili", "female", android. R. drawable.Ic_dialog_dialer), }; @ Override PublicView getView (IntPosition, View convertView, ViewGroup parent ){ LinearLayout line =Null; If(ConvertView! =Null){ Line = (LinearLayout) convertView; }Else{ Line = (LinearLayout) LayoutInflater.From(MainActivity.This). Inflate (R. layout.List_cell_view,Null); } ListCellData item = getItem (position ); ImageView image = (ImageView) line. findViewById (R. id.Icon); TextView name = (TextView) line. findViewById (R. id.Name); TextView dec = (TextView) line. findViewById (R. id.Dec); Image. setImageResource (item. getIcon ()); Name. setText (item. getUsername ()); Dec. setText (item. getSex ()); ReturnLine; } @ Override PublicLongGetItemId (IntPosition ){ ReturnPosition; } @ Override PublicListCellData getItem (IntPosition ){ ReturnData [position]; } @ Override PublicIntGetCount (){ ReturnData. length; } };