2、Theme_Black：
它的意思为默认状态下黑背景。 api原文如下：
Special variation on the default theme that ensures the background is completely black. This is useful for things like image viewers and media players. If you want the normal (dark background) theme do not use this, use Theme. 效果图如下：
2.1、Theme_Black_NoTitleBar： 意思为：黑背景主题的没有标题栏的样式 api原文：
Variant of the black theme with no title bar 效果图如下：
2.2、Theme_Black_NoTitleBar_Fullscreen 意思为：黑背景主题的没有标题栏且全屏的样式 api原文：
Variant of the black theme that has no title bar and fills the entire screen 效果图如下：
3、Theme_Light
意思为：默认状态下亮背景，与上述黑背景Theme_Black相反。 api原文：
Theme for a light background with dark text on top. Set your activity to this theme if you would like such an appearance. As with the default theme, you should try to assume little more than that the background will be a light color. 效果图如下：
