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為什么老師設(shè)置getTag在postExecute里?post里的操作只是貼圖,應(yīng)該在doinbackground里或之前設(shè)置的
2016-03-20
源自:Android必學(xué)-異步加載 3-3
正在回答
sorry,原來下節(jié)就講到流量的問題了。。。
可能我跳著看沒看清老師寫的,這是我自己寫的,可以用
? ? ? ? protected?Bitmap?doInBackground(String...?params)?{
????????????//?TODO?Auto-generated?method?stub
????????????String?url?=?params[0];
????????????Bitmap?bitmap?=?null;
????????????if(imageview.getTag()!=?null){
????????????????bitmap?=?(Bitmap)?imageview.getTag();
????????????}
????????????else{
????????????try?{
????????????????bitmap?=?BitmapFactory.decodeStream(new?URL(url).openStream());
????????????????imageview.setTag(bitmap);
????????????}?catch?(Exception?e)?{
????????????????e.printStackTrace();
????????????}?}
????????????return?bitmap;
????????}
就是在doinbackround中,當(dāng)?shù)谝淮蝕etTag為null時(shí)就下載圖片然后把bitmap設(shè)置為TAG,下次getTag不為null時(shí)就取出tag并返回這個(gè)tag
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2016-03-20
sorry,原來下節(jié)就講到流量的問題了。。。
2016-03-20
可能我跳著看沒看清老師寫的,這是我自己寫的,可以用
? ? ? ? protected?Bitmap?doInBackground(String...?params)?{
????????????//?TODO?Auto-generated?method?stub
????????????String?url?=?params[0];
????????????Bitmap?bitmap?=?null;
????????????if(imageview.getTag()!=?null){
????????????????bitmap?=?(Bitmap)?imageview.getTag();
????????????}
????????????else{
????????????try?{
????????????????bitmap?=?BitmapFactory.decodeStream(new?URL(url).openStream());
????????????????imageview.setTag(bitmap);
????????????}?catch?(Exception?e)?{
????????????????e.printStackTrace();
????????????}?}
????????????return?bitmap;
????????}
就是在doinbackround中,當(dāng)?shù)谝淮蝕etTag為null時(shí)就下載圖片然后把bitmap設(shè)置為TAG,下次getTag不為null時(shí)就取出tag并返回這個(gè)tag