Android -在ListView中显示背景图像


Android - Display background image in ListView

我是android的新手。我开始使用android才2天。我试着在谷歌上搜索我需要做什么才能在列表视图中制作背景图像,但所有的代码都太复杂了,我无法理解,所以请不要投票给我。

我的列表视图应该显示来自服务器的背景图像。我已经完成了将我的应用程序连接到服务器。我可以显示图像的url

下面是我的php代码:

AndroidHome.php

<?php
$con = mysql_connect("localhost", "load2unet_root", "hzXC3rUm");
if (!$con)
{
die('Could not connect: ' . mysql_error());
}
mysql_select_db("load2unet_db", $con);
$result = mysql_query("SELECT Photo FROM Home ORDER BY HomeID DESC");
while($row = mysql_fetch_assoc($result))
{
    $output[] = $row;
}
print(json_encode($output));
mysql_close($con);
?>

这是我的。java

HomeActivity.java

//@SuppressLint("NewApi")
public class HomeActivity extends ListActivity{

//String to display in ListView
String [] hello = {
        "Red",
        "Blue",
        "White",
        "Black",
        "Orange",
        "Pink"
};
ArrayList<String> arrayDataFromServer = new ArrayList<String>();
String array;
String [] thisarray;
@SuppressLint("NewApi")
@Override  
public void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    //setContentView(R.layout.activity_home); 
    StrictMode.enableDefaults();
    String result ="";
    InputStream isr = null;
    try{
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new     HttpPost("http://www.mysite.com/android/AndroidHome.php");
        HttpResponse response = httpclient.execute(httppost);
        HttpEntity entity = response.getEntity();
        isr = entity.getContent();
    }
    catch (Exception e)
    {
        Log.e("log_tag", "Error in http connection" +e.toString());
        //resultView.setText("Couldn't connect to database");
    }
    try {
        BufferedReader reader = new BufferedReader(new    InputStreamReader(isr, "iso-8859-1"), 8);
        StringBuilder sb = new StringBuilder();
        String line = null;
        while ((line = reader.readLine()) != null)
        {
            sb.append(line + "'n");
        }
        result = sb.toString();
        Log.e("log_tag", "BufferedReader:" +result);
    }
    catch(Exception e)
    {
        Log.e("log_tag, Error converting result"+e.toString(), result);
    }
    try {
        String s = "";
        JSONArray jArray = new JSONArray(result);
        for (int i = 0; i< jArray.length(); i++)
        {
            JSONObject json = jArray.getJSONObject(i);
            array=json.getString("Photo");
            arrayDataFromServer.add(array);
            Log.e("log_tag", "Array: " +array);
            Log.e("log_tag", "arrayDataFromServer: " +arrayDataFromServer);
        }
    }
    catch (Exception e)
    {
        Log.e("log_tag", "Error Parsing Data"+e.toString());
    }
    setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrayDataFromServer));
}
public void onListItemClick(
        ListView parent, View v, int position, long id)
{
    //Toast.makeText(this, "You have selected" + colors[position], Toast.LENGTH_LONG).show();
}

}

activity_home.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical">
    <!-- Main ListView
         Always give id value as list(@android:id/list)
    -->

    <ListView
        android:id="@+id/listView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </ListView>
</LinearLayout>

我在想,在setListAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrayDataFromServer));我可以使用一些不同的代码来显示它在背景图像?

任何帮助都将非常感激。提前感谢!

编辑

String urlString = URLEncoder.encode(array);
            URL url = new URL(urlString);
            Bitmap bm = BitmapFactory.decodeStream(url.openConnection().getInputStream());
            Drawable dr = new BitmapDrawable(bm); // that's the bitmap you downloaded from your server
            getListView.setBackground(dr);

回答你的问题:

 // you can call this from inside the ListActivity
 Drawable dr = new BitmapDrawable(bitmap); // that's the bitmap you downloaded from your server
 getListView().setBackground(dr);

给新手额外的建议:

不要使用StrictMode.enableDefaults();,因为你正在屏蔽一个非常好的保护,以防止不良代码。学习如何正确地做这件事。AsyncTask是一个非常流行且非常容易使用的线程平台,你应该使用它。如果你觉得有信心和冒险使用加载器,这是更复杂,但更强大!