Android listview layout (inheriting listactivity and using arrayadapter)

 

 

Using listview and arrayadapter layout is the simplest of listview layout. First, we will create a component to display data, such as main. xml

 

<? XML version = "1.0" encoding = "UTF-8"?> <! -- The main interface itself is a display component --> <textview xmlns: Android = "http://schemas.android.com/apk/res/android" Android: layout_width = "fill_parent" Android: layout_height = "fill_parent" Android: padding = "10dp" Android: textsize = "16sp"> </textview>

　　

The activity code is as follows:

 

Package cn.com. android. GRID; import android. app. listactivity; import android. OS. bundle; import android. widget. arrayadapter; public class listviewtest extends listactivity {@ override protected void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); string data [] = getdata (); arrayadapter <string> arrayadapter = new arrayadapter <string> (this, R. layout. main, data); this. setlistadapter (arrayadapter); // arrayadapter inherits from baseadapter, baseadapter inherits from listadapter}/*** @ author chenzheng_java * @ description to get an array list */private string [] getdata () {string [] DATA = new string [100]; for (INT I = 0; I <100; I ++) {data [I] = "list item" + I;} return data ;}}

If the activity does not want to inherit the listactivity, we can write it like this.

 

Package cn.com. android. GRID; import android. app. activity; import android. OS. bundle; import android. widget. arrayadapter; import android. widget. listview; public class listviewtest2 extends activity {@ override protected void oncreate (bundle savedinstancestate) {super. oncreate (savedinstancestate); listview = new listview (this); listview. setadapter (New arrayadapter <string> (this, R. layout. main, getdata (); setcontentview (listview);}/*** @ author chenzheng_java * @ description get an array list */private string [] getdata () {string [] DATA = new string [100]; for (INT I = 0; I <100; I ++) {data [I] = "list item" + I;} return data ;}}

　　

Waste of words:

There is a big gap between the two implementation methods, and many beginners may be dizzy. But it doesn't matter. Let's take a look at how listactivity is implemented.

The Code excerpt is as follows:

 

public class ListActivity extends Activity {      /**      * This field should be made private, so it is hidden from the SDK.      * {@hide}      */      protected ListAdapter mAdapter;      /**      * This field should be made private, so it is hidden from the SDK.      * {@hide}      */      protected ListView mList;  

　　

We can see that, in fact, when we inherit the listactivity, there is actually a listview inherited from the listactivity, so do not think that the gap is very large, in essence, the implementation steps are the same. You can think that android provides you with a free tool class. Nothing unusual.

The steps are three major steps:

Step 1: Prepare the layout file main. xml

Step 2: Get the data getdata ()

 

Step 3: bind the data source setlistadapter ();