- <TextView
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_centerhorizontal="true"
- android:layout_centervertical="true"
- android:text="@string/hello_world"
- tools:context=". Mainactivity " />
Always for tools:context=. " Mainactivity "This sentence does not understand, today looked under, found is this:
tools:context= the phrase "activity name" will not be packaged into the APK. Just the layout editor of ADT sets the corresponding render context in your current layout file, indicating that the rendering context of your current layout is the activity that the activity name corresponds to. If the activity has a theme set in the manifest file, the ADT Layout Editor will render your current layout based on this theme. That is, if you set the mainactivity set a theme.light (others can also), then you see in the visual layout manager of the background of a control ah or something should be theme.light look. Just to show you what you see and what you get.
Tools:context= ". The role of Mainactivity