Android - When and for which purpose we use the following prefixes in android xml file?
问题 I am new to android development and confused about the following prefixes: xmlns:android xmlns:app xmlns:tools android:something app:something tool:something I am confused about them because sometimes I use one, and android studio marks it as red underline which means i should use another one, and when sometimes i use another one android studio marks it with red line which means i should use the other one and so on, which makes me confused. And even in some cases i noticed that we are not