Learn Android simpleadapter Display Network pictures

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The main knowledge of this program is: Simpleadapter itself is not support network pictures, if in Map.put (A, A, b) is a bitmap, the program does not report red font, but in the console output green font, as follows

05-10 15:46:45.474:i/system.out (846): ResolveUri failed on bad bitmap uri: [email protected]

To implement the display network picture is actually very simple, using the method in Simpleadapter Simpleadapter.setviewbinder ().

Simpleadapter.setviewbinder (New Viewbinder () {@Overridepublic Boolean setviewvalue (View view, Object data,string Textrepresentation) {if (view instanceof ImageView && data instanceof Bitmap) {ImageView IV = (ImageView) view;iv. Setimagebitmap ((Bitmap) data); return true;} return false;}});

New Simpleadapter (Mainactivity.this,getdata (), r.layout.t, new string[] {"Images"},new int[] {r.id.imageview_main});

There are three parameters view,data,textrepresentation, say the first two parameters, view is your custom layout (such as R.LAYOUT.T) all the components, the program will traverse the component in the layout, data is you preach

list<map<, >> (GetData () method, returns a list<map<, >>), the program iterates through each item of data. Next, use the IF () statement to filter on it.

Since it is a network picture, it requires permission

<uses-permission android:name= "Android.permission.INTERNET"/>

The code is as follows:

Mainactivity.java

public class Mainactivity extends Actionbaractivity {listview listview; list<map<string,?>> data; String str[] = {"",//Add image URL for h t T P:/"", "", ""}; @Overridepublic void OnCreate (Bundle savedinstancestate) {s Uper.oncreate (savedinstancestate); Setcontentview (r.layout.activity_main); listview = (ListView) Findviewbyid ( R.id.lv_main); Simpleadapter simpleadapter = new Simpleadapter (Mainactivity.this,getdata (), r.layout.t, new string[] {"Images"},new in T[] {r.id.imageview_main}), Simpleadapter.setviewbinder (new Viewbinder () {@Overridepublic Boolean setviewvalue (View View, Object data,string textrepresentation) {if (view instanceof ImageView && data instanceof Bitmap) {ImageView IV = (ImageView) view;iv.setimagebitmap ((Bitmap) data); return true;} return false;}}); Listview.setadapter (Simpleadapter);} Public list<map<string,?>> GetData () {data = new arraylist<map<string,?>> (); for (int i = 0; I &l T Str.length; i++) {map<string, OBJECT&GT Map = new hashmap<string, object> (), Map.put ("Images", Returnbitmap (Str[i]));d ata.add (map); return data;} Public Bitmap returnbitmap (String url) {URL myfileurl = null; Bitmap Bitmap = null;try {myfileurl = new URL (URL),} catch (Malformedurlexception e) {e.printstacktrace ();} try {HttpURLConnection conn = (httpurlconnection) myfileurl.openconnection (); Conn.setdoinput (true); Conn.connect (); I Nputstream is = Conn.getinputstream (), bitmap = Bitmapfactory.decodestream (is); Is.close (); catch (IOException e) {e.printstacktrace ();} return bitmap;}}

Activity_main.xml

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "    android:orientation=" vertical "    android:layout_width=" fill_parent "    android:layout_height=" Fill_parent "    ><listview     android:id=" @+id/lv_main "    android:layout_width=" Fill_parent    " android:layout_height= "Fill_parent" ></ListView> </LinearLayout>

customizing layout files

T.xml

<?xml version= "1.0" encoding= "Utf-8"? ><linearlayout xmlns:android= "http://schemas.android.com/apk/res/ Android "    android:layout_width=" match_parent "    android:layout_height=" match_parent "    android:o rientation= "vertical" >        <imageview         android:id= "@+id/imageview_main"        android:layout_width= " 80DP "        android:layout_height=" 80DP "/></linearlayout>