[Android] listview drag a black screen, SQL Delete, display the list of dialog, list long by event, split line

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• Solution:

Solution:

Http://my.oschina.net/haquanwen/blog/54394

Listview is a commonly used display control. The default background is the same transparent color as the system window. If a background image or background color is added to listview, The listview will be black when scrolling, because, during scrolling, when the view in the list is re-painted, the system still uses the default transparent color. The color value is # ff191919. to change this situation, you only need to call setcachecolorhint (0) of listview and set the color value to 0 or the attribute Android: cachecolorhint = "#00000000" of listview in XML files. When scrolling, there is no background color when you redraw the view.

Note: yes #000000000 instead of #000000, or @ color/transparent can be used.

 

SQL delete:

if(db.delete("rss_channel", "_id = ? ", new String[]{channel.get_id()+""}) > 0)

 

Display the dialog of the list:

No title is set. No title is automatically displayed.

New alertdialog. builder (homeactivity. this ). setitems (New String [] {"go", "delete"}, new dialoginterface. onclicklistener (){......}). create (). show ();

 

 

The long-pressed list event has the same parameters as short-pressed events, so there is almost no difference in usage.

 

Split line:

<View android:layout_width="fill_parent"        android:layout_height="2dip"        android:background="#FF909090"        android:layout_marginTop="5dip"        android:layout_marginBottom="5dip"/>