The technical principle of the CircleImageView framework in the Java class library

The technical principle of the CircleImageView framework in the Java class library CircleImageView is a common circular avatar control that is widely used in the Java library.This article will introduce the technical principles and implementation methods of the CircleImageView framework. 1. Technical principles The technical principle of the CircleImageView framework is Java -based graphical processing technology.This framework mainly achieves the display and tailoring of the round avatar through the following points: 1. Inherit the ImageView class: CircleImageView class inherits from the ImageView class, so as to obtain some basic attributes and methods of the ImageView class. 2. Custom cutting: CircleImageView By rewriting the ONDRAW method, using the PATH path object to define a circular area before drawing the avatar.Then, we set the circular area as the cornering path to the Canvas object, so that it will only be displayed in the circular area when drawing the avatar. 3. Adaptive size: CircleImageView determines the final display of the final displayed avatar according to the size of ImageView itself and the scaletype set by the user.This can ensure the adaptive display of the avatar under different screen size. 4. Image loading and cache: CircleImageView framework is usually used together with the picture loading library (such as Glide, Picasso, etc.). Load the picture from the network or local local loading library to implement the cache of the picture.This can speed up the loading speed of the picture and avoid repeated loading. 2. Example code The following is a simple example code that shows how to use the CircleImageView framework to achieve a circular avatar display in the Java library. CircleImageView circleImageView = new CircleImageView(context); circleImageView.setImageResource(R.drawable.avatar); circleImageView.setBorderColor(getResources().getColor(R.color.border_color)); circleImageView.setBorderWidth(2); circleImageView.setShadowEnabled(true); circleImageView.setShadowRadius(4); circleImageView.setShadowColor(getResources().getColor(R.color.shadow_color)); In the above code, we first create a CircleImageView object and pass in a context.Then, we set the resource ID of the avatar through the SetImageReSource method, and set the color and width of the round border through SetBorderColor and the SetBorderWidth method.Then, we call Setshadowenabled, Setshadowradius and SetshadowColor methods to set whether to open the shadow effect and the radius and color of the shadow. Finally, we can add CircleImageView to the layout for display. 3. Summary This article introduces the technical principles and implementation methods of the CircleImageView framework in the Java library.By inheriting the technologies such as the ImageView class, custom tailoring, adaptive size, and picture loading and cache, CircleImageView can easily achieve the display and style settings of round avatar.I hope this article can help you understand the CircleImageView framework.