In Android, the overall background turns black when listview sets the background image and is dragged.

In Android, listview is a commonly used control. When we use it, we often encounter the phenomenon that the entire view is dimmed after clicking, which is particularly evident after setting the background image.
Starting from the effect of listview, the default listitem background is transparent, while the background of listview is fixed, therefore, if the display content of each item is mixed with the background in real time during the scroll bar process, the android system uses Android: cachecolorhint to optimize this process.
In the black topic, the default color value is #191919, so the entire view is dimmed.
To solve this problem, you only need a line of code. If you only change the background color, you can directly specify the Android: cachecolorhint as the color you want. If you use an image as the background, you only need to specify Android: cachecolorhint as transparent (#00000000.
Method 1: Add the following attributes to the layout file: Android: cachecolorhint = "#00000000 ″.
Method 2: In the Java file, for listactivity, use this in oncreate. getlistview () first obtains the listview, and then calls the listview method: setcachecolorhint (color. transparent), set the background to transparent.