I came across stormzhang’s Tencent interview questions and decided to work through them, documenting my answers and thought process. Topics covered: Android fundamentals (processes, Activities, Handler) Screen density and resource qualifiers Thread synchronization in Java System design (resumable downloads, network architecture) ...
Ever since getting a Nexus device, I never wanted to plug in a USB cable again. Android supports ADB debugging over WiFi, making cable-free development a reality. ...
SQLite is a lightweight relational database engine built into Android, ideal for local data persistence. The android.database.sqlite package provides everything you need without additional setup. ...
The Palette library, part of Android Support Library (now migrated to AndroidX palette), extracts representative colors from a Bitmap. In Material Design, deriving UI colors from imagery is a common pattern, and Palette makes this straightforward. ...
Parallax scrolling is a common UI effect where different layers move at different speeds during scrolling, creating a sense of depth. ...
RecyclerView is a more flexible replacement for ListView. According to the official documentation, it efficiently maintains a limited collection of scrolling data items, and is recommended when your Views need to interact with user gestures and network data. ...
Canvas clipping limits the drawing region: only content within the clipped area is visible. ...
A View renders its content by “drawing” — using a canvas (Canvas) and a paintbrush (Paint). The Canvas obtained through the onDraw method is directly composited onto the View. ...
...
When you first start writing custom Views in Android, it’s common to feel unsure where to begin. Generally, there are two approaches: From scratch: Extend View and implement the appearance entirely through calculation and drawing. Extend an existing View: Add child views to an existing component, or override methods to change its behavior. ...