從緩存中存儲和加載圖像，圖像將存儲但不會加載

我有從服務器下載圖像或圖像集並顯示它們的功能。這部分工作正常，但我想將它們存儲在緩存中以使用應用程序保存用戶數據。從緩存中存儲和加載圖像，圖像將存儲但不會加載

我跟着this將緩存過程合併到我現有的函數中。

這是我imageload類：

package ui; 

import android.content.Context; 
import android.graphics.Bitmap; 
import android.graphics.BitmapFactory; 
import android.os.AsyncTask; 
import android.util.Log; 
import android.widget.ImageButton; 
import android.widget.ImageView; 

import java.io.InputStream; 
import java.net.URL; 
import java.util.Collections; 
import java.util.Map; 
import java.util.WeakHashMap; 
import java.util.concurrent.ExecutorService; 
import java.util.concurrent.Executors; 

/** 
* Created by paul on 15/08/2015. 
*/ 
public class loadImage extends AsyncTask<String, String, Bitmap> { 

    private Bitmap bitmap = null; 
    private String type = ""; 
    private ImageView imageView = null; 
    private ImageButton imageButton = null; 
    public int size = 0; 
    public boolean cache = true; 
    private Map<ImageButton, String> imageViewBtn; 
    private Map<ImageView, String> imageViewView; 
    private ExecutorService executorService; 
    private FileCache fileCache; 
    private MemoryCache memoryCache; 
    private String url = ""; 

    public loadImage (String type, Object object, Context context){ 
     memoryCache = new MemoryCache(); 
     if(type.equalsIgnoreCase("imagebutton")){ 
      imageButton = (ImageButton) object; 
      imageViewBtn = Collections.synchronizedMap(new WeakHashMap<ImageButton, String>()); 
     } else { 
      imageView = (ImageView) object; 
      imageViewView = Collections.synchronizedMap(new WeakHashMap<ImageView, String>()); 
     } 
     fileCache = new FileCache(context); 
     executorService = Executors.newFixedThreadPool(5); 
    } 

    @Override 
    protected void onPreExecute() { 
     super.onPreExecute(); 
     //add loader as BG 
    } 
    @Override 
    protected Bitmap doInBackground(String... params) { 
     //check if cache is true 
     url = params[0]; 
     try { 
      bitmap = BitmapFactory.decodeStream((InputStream) new URL(url).getContent()); 

     } catch (Exception e) { 
      e.printStackTrace(); 
     } 
     return bitmap; 

    } 
    protected void onPostExecute(Bitmap image) { 
     if(size != 0){ 
      image = Bitmap.createScaledBitmap(image, size, size, false); 
     } 
     if(type.equalsIgnoreCase("imagebutton")){ 
      imageButton.setImageBitmap(image); 
      imageViewBtn.put(imageButton, url); 
     } else { 
      imageButton.setImageBitmap(image); 
      imageViewBtn.put(imageButton, url); 
     } 
     memoryCache.put(url,image); 
    } 

    public boolean cache(String url) { 
     bitmap = memoryCache.get(url); 
     if(bitmap != null) { 
      Log.d("CACHE", "Image loaded from cache"); 
      if(type.equalsIgnoreCase("imagebutton")){ 
       imageButton.setImageBitmap(bitmap); 
      } else { 
       imageButton.setImageBitmap(bitmap); 
      } 
      return true; 
     } 
     return false; 
    } 
}

在我的日誌，它說的是，圖像被存儲在緩存中，但是當我在我的設備設置檢查緩存量永遠不會改變。我如何得到這個工作。

而且該類稱爲是這樣的：

//activity is the activity so ie login.this or whatever activity im currently in 
ImageButton pp = (ImageButton) custom.findViewById(R.id.search_pp); 
loadImage loadImage = new loadImage("imagebutton", pp, activity); 
if (!loadImage.cache(thumb)) { 
    loadImage.execute(thumb); 
}

來源

2015-08-16 Paul Ledger