aysnctask将所有图像下载到listview中的相同项目

I'm using asynctask to download image to listview with custom cursoradapter. The images are downloaded to the first item in the list and when I scroll down to the second and so on. It's not synchronize and it's not the right picture. What am I doing wrong? I cant upload pictures so here is my code:I'm using asynctask to download image to listvi