Android Photo Wall application, no amount of pictures are not afraid to crash

Photo wall This kind of function is quite common now, in many applications you can often see the shadow of the picture wall. Its design is actually very simple, with a GridView control as a "wall", and then along with the GridView rolling a picture affixed to the "wall", these photos can be stored on the phone locally, can also be downloaded from the Internet. To make an application similar to this one, there is a very important question to consider when the picture resources should be released. Because with the GridView scrolling, the load of pictures may be more and more, if there is no reasonable mechanism for the release of the picture, then when the picture reached a certain limit, the program will inevitably crash.

Today, the implementation of our photo wall application focuses on how to prevent the program from collapsing because of too many pictures. The main core algorithm uses the LRUCache class provided in Android, which is provided in version 3.1, and you need to import a ANDROID-SUPPORT-V4 jar package if you are developing it in an earlier version of Android.

For detailed explanation of LRUCache usage, you can refer to the Android high efficient loading and mapping scheme to effectively avoid program oom.

So let's start with a new Android project called Photowalldemo, where I'm using the Android 4.0 API.

The first question to consider is, where do we collect so many pictures? Here I have from Google's official demo to take out the image source, we will download the images from these URLs, the code is as follows:

public class Images {public final static string[] Imagethumburls = new string[] {"Https://lh  
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