Zho:背景换成下一个（积木）

The Next Backdrop block is a Looks block and a Stack block. The block changes the backdrop to the next in the list of backdrops, but if the current backdrop is the last in the list, the block will loop to the first.

The equivalent for a sprite is the Next Costume block, though sprites do not have an event hat block for changing costumes.

History
Prior to Scratch 2.0, this block was called Next Background and did not fire an event upon running. During 2.0 development, this block was also called "Next Scene".

Example Uses
This block is mainly used in animation scripts, in which the Stage will progress through its backdrops as with stop motion animation. The Wait Secs block is often used along with it to improve the animation speed.

Alternatively, it can be used for slideshow-style projects as shown below: 當 [空白 v] 鍵被按下 下一個背景

Workaround
This block may simply be replicated with the following code: 背景換成 [下一個背景 v] Also, because this block simply advances the backdrop number, the following code can do this: 背景換成 ((背景编号) + (1))

To get the effect of the nonexistent Previous Backdrop block, the addition can be changed to subtraction.

Removal
Many users have made suggestions about removing this block, insisting that its alternative is perfectly fine to use; however, others have disagreed, saying that it saves lots of time and is handy for animation.

The Scratch Team has made no comment on the matter, but is likely to keep the block for its handiness; it has been in Scratch since Scratch 1.0.