Android Flickr Jsonキャッシング画像

Question

Flickr Json画像をキャッシュして高速なローディングとオフライン使用のためにキャッシュする方法を教えていただけたらと思っています。下のコードはチュートリアルのものです。 Androidデベロッパーのリソースやその他の例をウェブで読み書きしようとすると失われてしまいます...解決策には非常に感謝して、この仕事をするのに役立ちます...私はプログラミングの初心者で、知識がありがとうございます:)

package com.windmillagency; 

import java.io.BufferedReader; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.io.Reader; 
import java.net.HttpURLConnection; 
import java.net.MalformedURLException; 
import java.net.URL; 

import org.apache.http.HttpEntity; 
import org.apache.http.client.ClientProtocolException; 
import org.apache.http.client.HttpClient; 
import org.apache.http.client.methods.HttpGet; 
import org.apache.http.impl.client.DefaultHttpClient; 
import org.json.JSONArray; 
import org.json.JSONException; 
import org.json.JSONObject; 








import android.app.ProgressDialog; 
import android.content.Context; 
import android.graphics.Bitmap; 
import android.graphics.BitmapFactory; 
import android.os.Bundle; 
import android.os.Handler; 
import android.os.Message; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.view.ViewGroup.LayoutParams; 
import android.widget.BaseAdapter; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.Gallery; 
import android.widget.ImageView; 
import android.widget.LinearLayout; 
import android.widget.Toast; 

public class AndroidFlickrActivity extends BT_activity_base { 



    public String thisActivityName = "Flickr"; 

    ProgressDialog progressDialog; 
    BackgroundThread backgroundThread; 

    public class FlickrImage { 
     String Id; 
     String Owner; 
     String Secret; 
     String Server; 
     String Farm; 
     String Title; 

     Bitmap FlickrBitmap; 

     FlickrImage(String _Id, String _Owner, String _Secret, 
       String _Server, String _Farm, String _Title){ 
      Id = _Id; 
      Owner = _Owner; 
      Secret = _Secret; 
      Server = _Server; 
      Farm = _Farm; 
      Title = _Title; 

      FlickrBitmap = preloadBitmap(); 
     } 

     private Bitmap preloadBitmap(){ 
      Bitmap bm= null; 

      String FlickrPhotoPath = 
        "http://farm" + Farm + ".static.flickr.com/" 
        + Server + "/" + Id + "_" + Secret + "_m.jpg"; 

      URL FlickrPhotoUrl = null; 

      try { 
       FlickrPhotoUrl = new URL(FlickrPhotoPath); 

       HttpURLConnection httpConnection 
        = (HttpURLConnection) FlickrPhotoUrl.openConnection(); 
       httpConnection.setDoInput(true); 
       httpConnection.connect(); 
       InputStream inputStream = httpConnection.getInputStream(); 
       bm = BitmapFactory.decodeStream(inputStream); 

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

      return bm; 
     } 

     public Bitmap getBitmap(){ 
      return FlickrBitmap; 
     } 

    } 

    class FlickrAdapter extends BaseAdapter{ 
     private Context context; 
     private FlickrImage[] FlickrAdapterImage;; 

     FlickrAdapter(Context c, FlickrImage[] fImage){ 
      context = c; 
      FlickrAdapterImage = fImage; 
     } 

     public int getCount() { 
      // TODO Auto-generated method stub 
      return FlickrAdapterImage.length; 
     } 

     public Object getItem(int position) { 
      // TODO Auto-generated method stub 
      return FlickrAdapterImage[position]; 
     } 

     public long getItemId(int position) { 
      // TODO Auto-generated method stub 
      return position; 
     } 

     public View getView(int position, View convertView, ViewGroup parent) { 
      // TODO Auto-generated method stub 
      ImageView image; 
      if (convertView == null) { 
       image = new ImageView(context); 
       image.setLayoutParams(new Gallery.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT)); 
       image.setScaleType(ImageView.ScaleType.FIT_CENTER); 
       image.setPadding(8, 8, 8, 8); 
      } else { 
       image = (ImageView) convertView;  
      } 

      image.setImageBitmap(FlickrAdapterImage[position].getBitmap()); 

      return image; 
     } 

    } 

    FlickrImage[] myFlickrImage; 

    /* 
    * FlickrQuery = FlickrQuery_url 
    * + FlickrQuery_per_page 
    * + FlickrQuery_nojsoncallback 
    * + FlickrQuery_format 
    * + FlickrQuery_tag + q 
    * + FlickrQuery_key + FlickrApiKey 
    */ 

    String FlickrQuery_url = "http://api.flickr.com/myflickrURL"; 
    String FlickrQuery_per_page = "&per_page=10"; 
    String FlickrQuery_nojsoncallback = "&nojsoncallback=1"; 
    String FlickrQuery_format = "&format=json"; 
    String FlickrQuery_tag = "&tags="; 
    String FlickrQuery_key = "&api_key="; 

    // Apply your Flickr API: 
    // www.flickr.com/services/apps/create/apply/? 
    String FlickrApiKey = "xxxxxxxxxxxxxxxxxxx"; 


    final String DEFAULT_SEARCH = "flickr"; 

    EditText searchText; 
    Button searchButton; 

    Gallery photoBar; 

    Bitmap bmFlickr; 

    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     this.activityName = "AndroidFlickrActivity"; 
     BT_debugger.showIt(activityName + ":onCreate"); 

     //reference to base layout.. 
      LinearLayout baseView = (LinearLayout)findViewById(R.id.baseView); 

      //setup background colors... 
      BT_viewUtilities.updateBackgroundColorsForScreen(this, this.screenData); 

      //setup background images.. 
      if(backgroundImageWorkerThread == null){ 
       backgroundImageWorkerThread = new BackgroundImageWorkerThread(); 
       backgroundImageWorkerThread.start(); 
      }   

      //setup navigation bar... 
      LinearLayout navBar = BT_viewUtilities.getNavBarForScreen(this, this.screenData); 
      if(navBar != null){ 
       baseView.addView(navBar); 
      } 

      //inflate this screens layout file... 
      LayoutInflater vi = (LayoutInflater)thisActivity.getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      View thisScreensView = vi.inflate(R.layout.flickr, null); 

      //add the view to the base view... 
      baseView.addView(thisScreensView); 

     searchText = (EditText)findViewById(R.id.searchtext); 
     searchText.setText(DEFAULT_SEARCH); 
     searchButton = (Button)findViewById(R.id.searchbutton); 

     photoBar = (Gallery)findViewById(R.id.photobar); 

     searchButton.setOnClickListener(searchButtonOnClickListener); 
    } 

    private Button.OnClickListener searchButtonOnClickListener 
    = new Button.OnClickListener(){ 

     public void onClick(View arg0) { 
      // TODO Auto-generated method stub 
      progressDialog = ProgressDialog.show(AndroidFlickrActivity.this, 
        "Progress", "Wait!"); 

      backgroundThread = new BackgroundThread(); 
      backgroundThread.setRunning(true); 
      backgroundThread.start(); 




     }}; 


    private String QueryFlickr(String q){ 

     String qResult = null; 

     String qString = 
       FlickrQuery_url 
       + FlickrQuery_per_page 
       + FlickrQuery_nojsoncallback 
       + FlickrQuery_format 
       + FlickrQuery_tag + q 
       + FlickrQuery_key + FlickrApiKey; 

     HttpClient httpClient = new DefaultHttpClient(); 
     HttpGet httpGet = new HttpGet(qString); 

     try { 
      HttpEntity httpEntity = httpClient.execute(httpGet).getEntity(); 

      if (httpEntity != null){ 
       InputStream inputStream = httpEntity.getContent(); 
       Reader in = new InputStreamReader(inputStream); 
       BufferedReader bufferedreader = new BufferedReader(in); 
       StringBuilder stringBuilder = new StringBuilder(); 

       String stringReadLine = null; 

       while ((stringReadLine = bufferedreader.readLine()) != null) { 
        stringBuilder.append(stringReadLine + "\n"); 
        } 

       qResult = stringBuilder.toString(); 
       inputStream.close(); 
      } 

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

     return qResult; 
    } 

    private FlickrImage[] ParseJSON(String json){ 

     FlickrImage[] flickrImage = null; 

     bmFlickr = null; 
     String flickrId; 
     String flickrOwner; 
     String flickrSecret; 
     String flickrServer; 
     String flickrFarm; 
     String flickrTitle; 

     try { 
      JSONObject JsonObject = new JSONObject(json); 
      JSONObject Json_photos = JsonObject.getJSONObject("photos"); 
      JSONArray JsonArray_photo = Json_photos.getJSONArray("photo"); 

      flickrImage = new FlickrImage[JsonArray_photo.length()]; 
      for (int i = 0; i < JsonArray_photo.length(); i++){ 
       JSONObject FlickrPhoto = JsonArray_photo.getJSONObject(i); 
       flickrId = FlickrPhoto.getString("id"); 
       flickrOwner = FlickrPhoto.getString("owner"); 
       flickrSecret = FlickrPhoto.getString("secret"); 
       flickrServer = FlickrPhoto.getString("server"); 
       flickrFarm = FlickrPhoto.getString("farm"); 
       flickrTitle = FlickrPhoto.getString("title"); 
       flickrImage[i] = new FlickrImage(flickrId, flickrOwner, flickrSecret, 
         flickrServer, flickrFarm, flickrTitle); 
      } 

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

     return flickrImage; 
    } 

    public class BackgroundThread extends Thread{ 
     volatile boolean running = false; 
     int cnt; 

     void setRunning(boolean b){ 
      running = b;  
      cnt = 10; 
     } 

     @Override 
     public void run() { 
      // TODO Auto-generated method stub 
      String searchQ = searchText.getText().toString(); 
      String searchResult = QueryFlickr(searchQ); 

      myFlickrImage = ParseJSON(searchResult); 


      handler.sendMessage(handler.obtainMessage()); 
     } 
    } 

    Handler handler = new Handler(){ 

     @Override 
     public void handleMessage(Message msg) { 
      // TODO Auto-generated method stub 

      progressDialog.dismiss(); 
      photoBar.setAdapter(new FlickrAdapter(AndroidFlickrActivity.this, myFlickrImage)); 
      Toast.makeText(AndroidFlickrActivity.this, 
        "Images Loaded", Toast.LENGTH_LONG).show(); 
     } 

    }; 

} 

Answer 1

ギブスでUniversal Image Loaderをご覧ください。

ユニバーサルImage Loaderを使用すると、リスト、ギャラリー、グリッド形式のAndroid上で画像の非同期画像の読み込み、キャッシュ、レンダリングを簡単に統合できます。独自のソリューションを実装したい場合は、このプロジェクトのソースを読むことは始めるのに最適です。これはSergey Tarasevichによって書かれ、BSD 3-clauseでライセンスされています。