LruCash使用showImageByThread有Bug
1．剛載入時，可見項目除了最後一個有載入圖片(有時還錯位)，其它只顯示ic_launcher
2．要滾動畫面好幾次才會全部載入對應的圖片
程式碼如下?
ImageLoader.java
ImageView?imageView;
String?url;
LruCache<String,?Bitmap>?bitmapLruCache;
public?ImageLoader()?{
????int?maxMemory?=?(int)?Runtime.getRuntime().maxMemory();
????int?cashSize?=?maxMemory?/?4;
????bitmapLruCache?=?new?LruCache<String,?Bitmap>(cashSize)?{
????????@Override
????????protected?int?sizeOf(String?key,?Bitmap?value)?{
????????????return?value.getByteCount();
????????}
????};
}
private?Handler?handler?=?new?Handler()?{
????@Override
????public?void?handleMessage(Message?msg)?{
????????if?(imageView.getTag().equals(url))?{
????????????imageView.setImageBitmap((Bitmap)?msg.obj);
????????}
????}
};
public?void?showImageByThread(ImageView?imageView,?final?String?url)?{
????this.imageView?=?imageView;
????this.url?=?url;
????Bitmap?bitmap?=?getBitmapFromCash(url);
????//緩衝沒有bitmap，從網路下載
????if?(bitmap?==?null)?{
????????new?Thread()?{
????????????@Override
????????????public?void?run()?{
????????????????Bitmap?bitmap?=?getBitmapFromURL(url);
????????????????//將下載的bitmap存到緩衝
????????????????addBitmapToCash(url,?bitmap);
????????????????Message?msg?=?Message.obtain();
????????????????msg.obj?=?bitmap;
????????????????handler.sendMessage(msg);
????????????}
????????}.start();
????}?else?{
????????imageView.setImageBitmap(bitmap);
????}
}
public?Bitmap?getBitmapFromURL(String?url)?{
????Bitmap?bitmap?=?null;
????try?{
????????URLConnection?connection?=?new?URL(url).openConnection();
????????InputStream?is?=?connection.getInputStream();
????????bitmap?=?BitmapFactory.decodeStream(is);
????????is.close();
????}?catch?(IOException?e)?{
????????e.printStackTrace();
????}
????return?bitmap;
}
public?void?addBitmapToCash(String?url,?Bitmap?bitmap)?{
????if?(bitmap?!=?null)?{
????????bitmapLruCache.put(url,?bitmap);
????}
}
public?Bitmap?getBitmapFromCash(String?url)?{
????return?bitmapLruCache.get(url);
}
2015-06-10
還有個可能，看你代碼你加載圖片的時候是不是調用的showImageByThread(ImageView?imageView,?final?String?url)
這個方法？
你這個loader中只有1個ImageView的引用，多次調用后，這個引用只指向最后一個ImageView，這也許就是為什么只有最后一個圖片顯示的原因吧。
顯示網絡圖片有好多庫可以用，universalImageLoader，google的volley。。。。。
2015-06-12
把new handler的操作放在你的showImageByThread（）里就可以了
2015-06-10
回復 iceliuorange：可以了，把圖片下載獨立成內部類，呼叫時把imageview和url傳進去
public?void?showImageByThread(ImageView?imageView,?final?String?url)?{ ????Bitmap?bitmap?=?getBitmapFromCash(url); ????//緩衝沒有bitmap，從網路下載 ????if?(bitmap?==?null)?{ ????????new?ImageHandlerThreat(imageView,?url).startThread(); ????}?else?{ ????????imageView.setImageBitmap(bitmap); ????} } private?class?ImageHandlerThreat?{ ????private?ImageView?imageView; ????private?String?url; ????private?Handler?handler?=?new?Handler()?{ ????????@Override ????????public?void?handleMessage(Message?msg)?{ ????????????if?(imageView.getTag().equals(url))?{ ????????????????imageView.setImageBitmap((Bitmap)?msg.obj); ????????????} ????????} ????}; ????public?ImageHandlerThreat(ImageView?imageView,?String?url)?{ ????????this.imageView?=?imageView; ????????this.url?=?url; ????} ????public?void?startThread()?{ ????????new?Thread()?{ ????????????@Override ????????????public?void?run()?{ ????????????????Bitmap?bitmap?=?getBitmapFromURL(url); ????????????????//將下載的bitmap存到緩衝 ????????????????addBitmapToCash(url,?bitmap); ????????????????Message?msg?=?Message.obtain(); ????????????????msg.obj?=?bitmap; ????????????????handler.sendMessage(msg); ????????????} ????????}.start(); ????} }2015-06-10
public?void?handleMessage(Message?msg)?{
????????if?(imageView.getTag().equals(url))?{
????????????imageView.setImageBitmap((Bitmap)?msg.obj);
????????}
????}
這里打個斷點，看是什么問題