Bild aus MySQL-Datenbank in Android-Studios abrufen

Question

Ich bin neu in Android Studios. Hier versuche ich, Bilder aus der MySQL-Datenbank, die auf einem Online-Server gespeichert ist, abzurufen und das Bild auf listvew anzuzeigen. Aber ich erhalte einen Fehler in meiner benutzerdefinierten Datei. Bitte hilf mir. this is the error i'm getting in log when i try to run my application

dies ist mein customJava code: paket com.example.manarpatel.book_app; Hier

import android.app.Activity; 
import android.graphics.Bitmap; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.ArrayAdapter; 
import android.widget.ImageView; 
import android.widget.TextView; 


public class CustomList extends ArrayAdapter<String> { 
private String[] urls; 
private Bitmap[] bitmaps; 
private Activity context; 

public CustomList(Activity context, String[] urls, Bitmap[] bitmaps) { 
    super(context, R.layout.image_list_view, urls); 
    this.context = context; 
    this.urls= urls; 
    this.bitmaps= bitmaps; 
} 

@Override 
public View getView(int position, View convertView, ViewGroup parent) { 

     LayoutInflater inflater = context.getLayoutInflater(); 
     View listViewItem = inflater.inflate(R.layout.image_list_view,parent, true); 

     TextView textViewURL = (TextView) listViewItem.findViewById(R.id.textViewURL); 
     ImageView image = (ImageView) listViewItem.findViewById(R.id.imageDownloaded); 

     textViewURL.setText(urls[position]); 

    Bitmap smaller = Bitmap.createScaledBitmap(bitmaps[position], 100, 50, false); 
    image.setImageBitmap(smaller); 
     // image.setImageBitmap(Bitmap.createScaledBitmap(bitmaps[position], 100, 50, false)); 

    return listViewItem; 
    } 
} 

, ist mein Imagelist-Viewer Java-Code:

package com.example.manarpatel.book_app; 

import android.app.ProgressDialog; 
import android.content.Intent; 
import android.os.AsyncTask; 
import android.os.Bundle; 
import android.support.v7.app.AppCompatActivity; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.ListView; 

import org.json.JSONException; 

import java.io.BufferedReader; 
import java.io.InputStreamReader; 
import java.net.HttpURLConnection; 
import java.net.URL; 


    public class ImageListView extends AppCompatActivity implements AdapterView.OnItemClickListener { 

    private ListView listView; 

    public static final String GET_IMAGE_URL="http://usedbookapp.esy.es/getAllImages.php"; 

    public GetAlImages getAlImages; 

    public static final String BITMAP_ID = "BITMAP_ID"; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_image_list_view); 

     listView = (ListView) findViewById(R.id.listView); 
     listView.setOnItemClickListener(this); 
     getURLs(); 
    } 

    private void getImages(){ 
     class GetImages extends AsyncTask<Void,Void,Void>{ 
      ProgressDialog loading; 
      @Override 
      protected void onPreExecute() { 
       super.onPreExecute(); 
       loading = ProgressDialog.show(ImageListView.this,"Downloading images...","Please wait...",false,false); 
      } 

      @Override 
      protected void onPostExecute(Void v) { 
       super.onPostExecute(v); 
       loading.dismiss(); 
       //Toast.makeText(ImageListView.this,"Success",Toast.LENGTH_LONG).show(); 
       CustomList customList = new CustomList(ImageListView.this,GetAlImages.imageURLs,GetAlImages.bitmaps); 
       listView.setAdapter(customList); 
      } 

      @Override 
      protected Void doInBackground(Void... voids) { 
       try { 
        getAlImages.getAllImages(); 

       } catch (JSONException e) { 
        e.printStackTrace(); 
       } 
       return null; 
      } 
     } 
     GetImages getImages = new GetImages(); 
     getImages.execute(); 
    } 

    private void getURLs() { 
     class GetURLs extends AsyncTask<String,Void,String>{ 
      ProgressDialog loading; 

      @Override 
      protected void onPreExecute() { 
       super.onPreExecute(); 
       loading = ProgressDialog.show(ImageListView.this,"Loading...","Please Wait...",true,true); 
      } 

      @Override 
      protected void onPostExecute(String s) { 
       super.onPostExecute(s); 
       loading.dismiss(); 
       getAlImages = new GetAlImages(s); 
       getImages(); 
      } 

      @Override 
      protected String doInBackground(String... strings) { 
       BufferedReader bufferedReader = null; 
       try { 
        URL url = new URL(strings[0]); 
        HttpURLConnection con = (HttpURLConnection) url.openConnection(); 
        StringBuilder sb = new StringBuilder(); 

        bufferedReader = new BufferedReader(new InputStreamReader(con.getInputStream())); 

        String json; 
        while((json = bufferedReader.readLine())!= null){ 
         sb.append(json+"\n"); 
        } 

        return sb.toString().trim(); 

       }catch(Exception e){ 
        return null; 
       } 
      } 
     } 
     GetURLs gu = new GetURLs(); 
     gu.execute(GET_IMAGE_URL); 
    } 

    @Override 
     public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) { 
     Intent intent = new Intent(this, ViewFullImage.class); 
     intent.putExtra(BITMAP_ID,i); 
     startActivity(intent); 
    } 
} 

Java-Code, um alle Bilder zu bekommen:

package com.example.manarpatel.book_app; 


import android.graphics.Bitmap; 
import android.graphics.BitmapFactory; 

import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 

import java.io.IOException; 
import java.net.MalformedURLException; 
import java.net.URL; 

public class GetAlImages { 

public static String[] imageURLs; 
public static Bitmap[] bitmaps; 

public static final String JSON_ARRAY="result"; 
public static final String IMAGE_URL = "url"; 
private String json; 
private JSONArray urls; 

public GetAlImages(String json){ 
    this.json = json; 
    try { 
     JSONObject jsonObject = new JSONObject(json); 
     urls = jsonObject.getJSONArray(JSON_ARRAY); 
    } catch (JSONException e) { 
     e.printStackTrace(); 
    } 
} 

private Bitmap getImage(JSONObject jo){ 
    URL url = null; 
    Bitmap image = null; 
    try { 
     url = new URL(jo.getString(IMAGE_URL)); 
     image = BitmapFactory.decodeStream(url.openConnection().getInputStream()); 
    } catch (MalformedURLException e) { 
     e.printStackTrace(); 
    } catch (IOException e) { 
     e.printStackTrace(); 
    } catch (JSONException e) { 
     e.printStackTrace(); 
    } 
    return image; 
} 

public void getAllImages() throws JSONException { 
    bitmaps = new Bitmap[urls.length()]; 

    imageURLs = new String[urls.length()]; 

    for(int i=0;i<urls.length();i++){ 
     imageURLs[i] = urls.getJSONObject(i).getString(IMAGE_URL); 
     JSONObject jsonObject = urls.getJSONObject(i); 
     bitmaps[i]=getImage(jsonObject); 
     } 
    } 
} 

hier, den XML-Code der Bildlistenansicht

<LinearLayoutandroid:orientation="horizontal"android:layout_width="fill_parent" android:layout_height="wrap_content"> 
<ImageView android:id="@+id/imageDownloaded" android:layout_width="wrap_content" android:layout_height="wrap_content" android:src="@drawable/abc_ic_menu_copy_mtrl_am_alpha"/> 
<TextView android:id="@+id/textViewURL" android:layout_width="wrap_content" android:layout_height="wrap_content"/> 

</LinearLayout> 

Answer 1

versuchen Sie, Glide zu verwenden, um ima zu recen ge aus der Datenbank

public class NetworkImageView extends ImageView { 

private String imageURL; 

/** 
* Resource ID of the image to be used as a placeholder until the network image is loaded. 
*/ 
private int mDefaultImageId; 

/** 
* Resource ID of the image to be used if the network response fails. 
*/ 
private int mErrorImageId; 

private Bitmap bitmap; 

public NetworkImageView(Context context) { 
    super(context); 
} 

public NetworkImageView(Context context, AttributeSet attrs) { 
    super(context, attrs); 
} 

public NetworkImageView(Context context, AttributeSet attrs, int defStyle) { 
    super(context, attrs, defStyle); 
} 

public String getImageURL() { 
    return imageURL; 
} 

public void setImageUrl(String imageURL) { 
    this.imageURL = imageURL; 
    Glide.with(getContext()) 
      .load(imageURL) 
      .override(200, 200) 
      .diskCacheStrategy(DiskCacheStrategy.ALL) 
      .into(this); 
} 

/** 
* Sets the default image resource ID to be used for this view until the attempt to load it 
* completes. 
*/ 
public void setDefaultImageResId(int defaultImage) { 
    mDefaultImageId = defaultImage; 
} 

/** 
* Sets the error image resource ID to be used for this view in the event that the image 
* requested fails to load. 
*/ 
public void setErrorImageResId(int errorImage) { 
    mErrorImageId = errorImage; 
} 

public void setLocalImageBitmap(Bitmap bitmap) { 
    this.bitmap = bitmap; 
} 

}

xml Lyaout:

<com.vynd.solution.utiles.NetworkImageView 
        android:id="@+id/backdrop" 
        android:layout_width="match_parent" 
        android:layout_height="match_parent" 
        android:background="@drawable/gradient" 
        android:scaleType="centerCrop" 
        android:src="@null" /> 

und verwenden diese

photo = (NetworkImageView) itemView.findViewById(R.id.photoItem); 

photo.setImageUrl(url); 

I dieser exemple hoffe, nützlich ist Mehr Infos Link

Answer 2

Sie können dies versuchen:

Picasso.with(this).load(imageURL).into(imageView); 

Dank