Question

我是Android的新手，在从服务器中存在的mysql数据库中检索图像URL时面临问题我可以使用Hashmap检索字符串，但无法从数据库中检索图像URL

我使用适配器类链接listview和imageview，textview等

任何人都可以检查下面的代码，以便我可以检索图像路径并将其链接到imageView 并显示数据库插入路径中的图像。

MainActivity.java

public class MainActivity extends Activity {
@SuppressLint("NewApi")
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Permission StrictMode
    if (android.os.Build.VERSION.SDK_INT > 9) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
    }

    // listView1
    final ListView lstView1 = (ListView)findViewById(R.id.listView1); 

    String url = "http://192.168.1.2/Android/App/sample.php";

    try {
        JSONArray data = new JSONArray(getJSONUrl(url));

        final ArrayList<HashMap<String, String>> MyArrList = new ArrayList<HashMap<String, String>>();
        HashMap<String, String> map;

        for(int i = 0; i < data.length(); i++){
            JSONObject c = data.getJSONObject(i);
            map = new HashMap<String, String>();
            map.put("title", c.getString("title"));
            map.put("artist", c.getString("artist"));
            map.put("duration", c.getString("duration"));
            map.put("image", c.getString("image")); i cant retrieve the image string here is the only problem


            MyArrList.add(map);
        }           

        lstView1.setAdapter(new ImageAdapter(this,MyArrList));

    } catch (JSONException e) {

        e.printStackTrace();
    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }


}


public class ImageAdapter extends BaseAdapter 
{
    private Context context;
    public ImageView imageView;
    private ArrayList<HashMap<String, String>> MyArr = new ArrayList<HashMap<String, String>>();

    public ImageAdapter(Context c, ArrayList<HashMap<String, String>> list) 
    {

        context = c;
        MyArr = list;
    }

    public int getCount() {

        return MyArr.size();
    }

    public Object getItem(int position) {

        return position;
    }

    public long getItemId(int position) {

        return position;
    }
    public View getView(int position, View convertView, ViewGroup parent) {


        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);


        if (convertView == null) {
            convertView = inflater.inflate(R.layout.activity_column, null); 
        }

        // ColImage
        imageView = (ImageView) convertView.findViewById(R.id.image);
        //imageView.getLayoutParams().height = 50;
        //imageView.getLayoutParams().width = 50;
        //imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
         try
         {
             URL url = new URL("image");
            Bitmap bmp = BitmapFactory.decodeStream(url.openConnection().getInputStream());
            imageView.setImageBitmap(bmp);
         } catch (Exception e) {
             // When Error
             imageView.setImageResource(android.R.drawable.ic_menu_report_image);
         }

        // ColPosition
        TextView tv_title = (TextView) convertView.findViewById(R.id.title);
        tv_title.setText("ID : " + MyArr.get(position).get("title"));

        // ColPicname
        TextView tv_artist = (TextView) convertView.findViewById(R.id.artist);
        //tv_artist.setPadding(50, 0, 0, 0);
        tv_artist.setText("Desc : " + MyArr.get(position).get("artist"));

        TextView tv_duration = (TextView) convertView.findViewById(R.id.duration);
        //tv_artist.setPadding(50, 0, 0, 0);
        tv_duration.setText("Desc : " + MyArr.get(position).get("duration"));

        TextView tv_link = (TextView) convertView.findViewById(R.id.link);
        //tv_artist.setPadding(50, 0, 0, 0);
        tv_link.setText("Desc : " + MyArr.get(position).get("link"));

        return convertView;

    }

} 

/*** Get JSON Code from URL ***/
public String getJSONUrl(String url) {
    StringBuilder str = new StringBuilder();
    HttpClient client = new DefaultHttpClient();
    HttpGet httpGet = new HttpGet(client);
    try 
    {
        HttpResponse response = client.execute(httpGet);
        StatusLine statusLine = response.getStatusLine();
        int statusCode = statusLine.getStatusCode();
        if (statusCode == 200) 
        { 
            HttpEntity entity = response.getEntity();
            InputStream content = entity.getContent();
            BufferedReader reader = new BufferedReader(new InputStreamReader(content));
            String line;
            while ((line = reader.readLine()) != null) 
            {
                str.append(line);
            }
        }   
        else 
        {
            Log.e("Log", "Failed to download file..");
        }
    } 
    catch (ClientProtocolException e) 
    {
        e.printStackTrace();
    } 
    catch (IOException e) 
    {
        e.printStackTrace();
    }
    return str.toString();
}


private static final String TAG = "ERROR";
private static final int IO_BUFFER_SIZE = 4 * 1024;
public static Bitmap loadBitmap(String url) {
    Bitmap bitmap = null;
    InputStream in = null;
    BufferedOutputStream out = null;

    try {
        in = new BufferedInputStream(new URL(url).openStream(), IO_BUFFER_SIZE);

        final ByteArrayOutputStream dataStream = new ByteArrayOutputStream();
        out = new BufferedOutputStream(dataStream, IO_BUFFER_SIZE);
        copy(in, out);
        out.flush();

        final byte[] data = dataStream.toByteArray();
        BitmapFactory.Options options = new BitmapFactory.Options();
        //options.inSampleSize = 1;

        bitmap = BitmapFactory.decodeByteArray(data, 0, data.length,options);
    } catch (IOException e) {
        Log.e(TAG, "Could not load Bitmap from: " + url);
    } finally {
        closeStream(in);
        closeStream(out);
    }

    return bitmap;
}

 private static void closeStream(Closeable stream) {
        if (stream != null) {
            try {
                stream.close();
            } catch (IOException e) {
                android.util.Log.e(TAG, "Could not close stream", e);
            }
        }
    }

 private static void copy(InputStream in, OutputStream out) throws IOException {
    byte[] b = new byte[IO_BUFFER_SIZE];
    int read;
    while ((read = in.read(b)) != -1) {
        out.write(b, 0, read);
    }
}



@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}}

sample.php

<?php
$con = mysql_connect("localhost","root","");
if (!$con){
die('Could not connect: ' . mysql_error());}
mysql_select_db("testdatabase", $con);
$result = mysql_query("SELECT * FROM sample");
while($row = mysql_fetch_assoc($result)){
    $output[] = $row;}

print(json_encode($output));
mysql_close($con);
?>

activity_column.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="@drawable/list_selector"
android:orientation="horizontal"
android:padding="5dip" >

<!--  ListRow Left sied Thumbnail image -->
<LinearLayout android:id="@+id/thumbnail" 
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:padding="3dip"      
    android:layout_alignParentLeft="true"
    android:background="@drawable/image_bg" 
    android:layout_marginRight="5dip">

    <ImageView
        android:id="@+id/image"   
        android:layout_width="50dip"
        android:layout_height="50dip"
       />

</LinearLayout>

<!-- Title Of Song-->
<TextView
    android:id="@+id/title"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignTop="@+id/thumbnail"
    android:layout_toRightOf="@+id/thumbnail"
    android:textColor="#040404"
    android:typeface="sans" 
    android:textSize="15dip"
    android:textStyle="bold"/>

<!-- Artist Name -->
<TextView
    android:id="@+id/artist"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_below="@id/title"
    android:textColor="#343434"
    android:textSize="10dip"
    android:layout_marginTop="1dip"
    android:layout_toRightOf="@+id/thumbnail"
    />

<!-- Rightend Duration -->
<TextView
    android:id="@+id/duration"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentRight="true"
    android:layout_alignTop="@id/title"
    android:gravity="right"
    android:layout_marginRight="5dip"
    android:textSize="10dip"
    android:textColor="#10bcc9"
    android:textStyle="bold"/>

 <!-- Rightend Arrow -->    
 <ImageView 
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:src="@drawable/arrow"
    android:layout_alignParentRight="true"
    android:layout_centerVertical="true"/>

 <TextView
     android:id="@+id/link"
     android:layout_width="wrap_content"
     android:layout_height="wrap_content"
     android:layout_alignBottom="@+id/thumbnail"
     android:layout_marginLeft="60dp"
     android:layout_toRightOf="@+id/title"
     />
</RelativeLayout>

数据库数据如下 enter image description here

我不知道我错过了哪些方法谢谢你的时间和关心我也无法检索图像路径检查图像路径是否正在检索我在mainActivity.java中创建了一个虚拟textview tv_link，但我得到的值为null

Answer 1

你使用了错误的IP方向。

如果您使用localhost来测试ip应该是'10 .0.0.2'而不是192.168.1.2必须是您的本地IP地址，但是在android仿真中localhost的地址不是172.0.0.1或者你的局域网IP 192.168.1.2

您必须使用10.0.0.2

String url = "http://10.0.0.2/Android/App/sample.php";

和

http://10.0.0.2/Android/pictures/sandeep1.jpg

在数据库中图片的网址

如果您确定url字符串很好，请尝试使用HttpURLConnection

try { URL url = new URL(imagen); HttpURLConnection connection = (HttpURLConnection)url.openConnection(); connection.setDoInput(true); connection.connect(); InputStream inputStream = connection.getInputStream(); foto = BitmapFactory.decodeStream(inputStream); } catch (MalformedURLException e) { e.printStackTrace(); }

如果有错误，将在catch块中详细说明

Android：无法从mysql数据库中检索图像URL并将其显示在imageView中

1 个答案: