overview
Android performance optimization is to improve the response speed, stability and user experience of the application. In application development, when the application encounters problems such as freezing, freezing, and slow operation, it will bring users a very poor experience and even lead to user loss. Performance optimization can effectively solve these problems and improve application quality and user satisfaction. In addition, the optimized application can also improve the battery life of the device and reduce the memory consumption, thereby increasing the service life of the device.
Causes of lag in Android application development
Stuck phenomena in Android application development are usually caused by the following reasons:
- UI thread is blocked: The UI thread is the thread responsible for rendering and updating the UI. If the UI thread is blocked, the interface will freeze. Common reasons for blocking the UI thread include time-consuming operations (such as IO operations, network requests, etc.), excessive drawing, and so on.
- Frequent garbage collection: Garbage collection will take a certain amount of time. If garbage collection is performed frequently, it will affect the response speed of the application. Common causes of frequent garbage collection include excessive creation of objects, memory leaks, etc.
- A large number of IO operations: IO operations are time-consuming operations. If there are a large number of IO operations in the application, it will affect the performance of the application.
- Excessive resource consumption: If the application excessively uses resources such as CPU and memory, it will cause the application to freeze. For example, there are memory leaks, a large number of Bitmap objects, etc. in the application.
Performance Optimization Solution
- Use asynchronous tasks and multi-threading technology to move time-consuming operations to background threads, avoiding time-consuming operations in the main thread.
- Optimize layout and rendering performance. Overlapping views and excessive layout levels can be avoided by using more optimized layout methods such as constraint layout. Additionally, hardware acceleration and caching techniques can be used to optimize rendering performance.
- Memory optimization. Reducing memory leaks and memory footprint reduces the risk of app jank. Memory optimization using the Android memory analysis tool can effectively identify and resolve memory leaks.
- Reduce IO operations and network requests. Using caching technology and as few network requests as possible can reduce the number of IO operations and network requests, thereby improving application performance.
- Use performance optimization tools to optimize. Use the performance optimization tools provided by Android Studio to identify performance problems in the application and provide corresponding solutions. For example, you can use Systrace to analyze your application's CPU usage and rendering performance, and use Profiler to identify memory leaks and CPU usage issues.
- Use animations and transitions appropriately. Too many animations and transition effects may cause the application to freeze, so use them according to actual needs.
- Regular app optimization. Continuous application optimization can continuously improve application performance and reduce the occurrence of stuttering.
Practical experience
In Android application development, lagging is a common problem that many developers will encounter. There may be many reasons for the freeze. The following will analyze the reasons that may cause the freeze from multiple dimensions, and give corresponding solutions and code examples.
Insufficient layout optimization
In Android application development, layout is a very important part, and an unreasonable layout may cause the application to freeze. Common layout optimization problems include:
- Nesting too deep: Nesting too many layout containers will lead to complex layout calculations, which will affect the performance of the application. Layout nesting should be minimized, and simple layout containers such as ConstraintLayout or LinearLayout should be used.
- Overdrawing: If a view is drawn beyond the bounds of its container, then the drawing of this view will affect the drawing of other views. Overdraw can be reduced by using a ViewStub to lazy load unnecessary views.
- Unreasonable layout attributes: Using unreasonable layout attributes may also cause the application to freeze. For example, if a layout container's width and height are both set to match_parent, it will occupy as much screen space as possible, thereby affecting the drawing of other views. The layout properties should be set reasonably according to actual needs.
Solution: Optimize the layout, minimize layout nesting, avoid overdrawing and use unreasonable layout attributes.
memory leak
Memory leaks are one of the common problems in Android application development, which can cause problems such as application freezes and crashes. Common memory leak issues include:
- Holding a static reference: If an object holds a static reference, it will not be recycled during the application life cycle, resulting in a memory leak. Static references should be avoided as much as possible.
- Hold Activity reference: If an object holds a reference to Activity, then when the Activity is destroyed, the object will continue to hold its reference, resulting in a memory leak. You should try to avoid holding a reference to the Activity in the object.
- Failure to release resources in time: If an object occupies a large amount of resources but does not release them in time, it will cause a memory leak. For example, a database connection was opened but not closed in a timely manner. Resources should be released in time to avoid memory leaks.
Solution: Pay attention to the life cycle of objects
Disk IO Disk IO is also another important reason for Android application lag. Disk IO refers to reading or writing files from disk. When performing disk IO, the application needs to access the storage device and wait for the operation to complete, which takes a long time. If disk IO is performed on the main thread, it will cause the main thread to block, thus causing the application to freeze.
solution:
(1) Use asynchronous threads to perform disk IO operations Applications can use asynchronous threads to perform disk IO operations, thereby avoiding blocking of the main thread. Android provides a variety of ways to implement asynchronous operations, such as AsyncTask, HandlerThread, and ThreadPoolExecutor. When performing disk IO operations, applications should place them in asynchronous threads.
(2) Using cache caching can effectively reduce the number of disk reads and writes, thereby improving application performance. Applications can cache frequently used data in memory or disk to avoid reading data from disk each time. For example, an LRU cache can be used to cache recently used data.
Code example:
typescriptCopy code// 使用AsyncTask执行磁盘IO操作
public class DiskIOTask extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... voids) {
// 执行磁盘IO操作
return null;
}
}
// 使用LRU缓存缓存数据
public class DataCache {
private static final int MAX_CACHE_SIZE = 100;
private static LinkedHashMap<String, String> sCache = new LinkedHashMap<String, String>(MAX_CACHE_SIZE, 0.75f, true) {
protected boolean removeEldestEntry(Map.Entry<String, String> eldest) {
return size() > MAX_CACHE_SIZE;
}
};
public static void put(String key, String value) {
sCache.put(key, value);
}
public static String get(String key) {
return sCache.get(key);
}
}
Other Reasons In addition to the above reasons, application freezing may also be related to other factors, such as network requests, drawing operations, memory leaks, etc. In order to avoid these problems, application developers should conduct a comprehensive analysis and optimization of the application.
To sum up, there are many reasons for Android application freezing, including main thread blocking, memory leaks, over-drawing, disk IO, etc. In order to avoid these problems, application developers should use asynchronous threads, optimize memory, reduce drawing, use cache and other methods to improve application performance. For more detailed Android performance optimization, you can refer to the "Android Performance Optimization Manual", which records 11 core performance optimization technology sections. Click to view detailed categories to get!
End of article
As an Android programmer for five years, I can tell you that Android performance optimization is very important in large companies, because both users and businesses, efficient and high-quality applications can bring excellent experience and business returns. Here are some reasons why Android performance optimization is so important:
- User Experience: Users are used to fast and efficient apps, and if the app is sluggish, freezes, or crashes, they are likely to abandon the app. Keeping your app as performant as possible can increase user retention and improve user ratings and positive word-of-mouth.
- Competitive advantage: The growing number of apps on the Android market also means that developers must capture every detail of the user experience to maintain a competitive advantage. Therefore, optimizing for performance issues can make your application more competitive with other applications.
- User traffic: The traffic of Android applications occupies a large part of mobile Internet traffic, so the performance of web pages and applications directly affects user experience and use.
- Device Compatibility: The performance of the same application on different devices varies greatly, which also shows that performance optimization on different types of devices is necessary and critical. If you do not consider the performance issues of adapting to different devices, users may also experience unsatisfactory experience.
- Moral duty: Android developers have a moral duty to do their best to have the best possible level of performance in their applications. Customers spend their time and money expecting that what they get is an approved application that also provides the basis for ongoing maintainability.
In general, in large companies, Android application performance optimization is not only a simple task, but also requires developers to have in-depth technical and experience literacy. Therefore, Android programmers in the industry should continue to learn and understand new technologies to ensure the performance and optimization of applications to improve their commercial value.