Android is a message driven, message driven several elements: The message says: Message Message queue: MessageQueue The news cycle, remove the message processing for circulation: Looper Message processing, message loop out messages from the message queue should be carried out after the processing of messages: Handler Usually we use most often is Message and Handler, if you use HandlerThread or similar HandlerThread things may come into contact with Looper, while

Subclass View onMeasure MeasureSpec setMeasureDimension onLayout layout(left, top, right, bottom) onDraw Canvas While viewgroups dont generally draw any content of their own,there are many situations where this could be useful,there are help instances where we can ask viewgroup to do some drawing.The first is inside the method dispatchDraw() after super.dispatchDraw has been called,at this stage,child views have already been drawn and we have an opportunity to do additional drawing on top.

System preferences In Apple Icon > System Preferences: Trackpad > Tap to click Keyboard > Key Repeat > Fast (all the way to the right) Keyboard > Delay Until Repeat > Short (all the way to the right) Dock > Automatically hide and show the Dock Homebrew install command line tools xcode-select --install,xcode-select -p /Library/Developer/CommandLineTools to check if command line tools is installed install homebrew ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"