经过FlutterLoader加载更新libapp.so文件完成动态化--代码编写（基于1.22以上版本，适用纯Flutter应用和混合应用）

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一.经过FlutterLoader加载更新libapp.so文件完成动态化--源码解析

1.1 拷贝ApplicationInfoLoader代码，重载load方法

final class KCApplicationInfoLoader {
    ....
     @NonNull
    public static FlutterApplicationInfo load(@NonNull Context applicationContext,String path) {
        ApplicationInfo appInfo = getApplicationInfo(applicationContext);
        // Prior to API 23, cleartext traffic is allowed.
        boolean clearTextPermitted = true;
        if (android.os.Build.VERSION.SDK_INT >= 23) {
            clearTextPermitted = NetworkSecurityPolicy.getInstance().isCleartextTrafficPermitted();
        }

        return new FlutterApplicationInfo(
                path,
                getString(appInfo.metaData, PUBLIC_VM_SNAPSHOT_DATA_KEY),
                getString(appInfo.metaData, PUBLIC_ISOLATE_SNAPSHOT_DATA_KEY),
                getString(appInfo.metaData, PUBLIC_FLUTTER_ASSETS_DIR_KEY),
                getNetworkPolicy(appInfo, applicationContext),
                appInfo.nativeLibraryDir,
                clearTextPermitted);
    }
}
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1.2 继承FlutterLoader，重写ensureInitializationComplete方法

public class KCFlutterLoader extends FlutterLoader {
    private static final String TAG = "KCFlutterLoader";
    private static KCFlutterLoader flutterLoaderInstance=new KCFlutterLoader();
    public static KCFlutterLoader getInstance() {
        return flutterLoaderInstance;
   }
    @Override
    public void startInitialization(@NonNull Context applicationContext) {
        Log.d(TAG,"KCFlutterLoader===startInitialization");
        super.startInitialization(applicationContext);
    }
    @Override
    public void ensureInitializationComplete(@NonNull Context applicationContext, @Nullable String[] args) {

        Log.d(TAG,"KCFlutterLoader===ensureInitializationComplete");
        File file=new File(applicationContext.getFilesDir(),"libappfix.so");
        if(file.exists()){
            String name=file.getAbsolutePath();
            FlutterApplicationInfo flutterApplicationInfo = KCApplicationInfoLoader.load(applicationContext, name);
            try {
                Class FlutterLoaderClass = Class.forName("io.flutter.embedding.engine.loader.FlutterLoader");
                Field nameField = FlutterLoaderClass.getDeclaredField("flutterApplicationInfo");
                nameField.setAccessible(true);
                nameField.set(this,flutterApplicationInfo);
               
                Field initialized = FlutterLoaderClass.getDeclaredField("initialized");
                initialized.setAccessible(true);
                // 这里是调试方便默认设置为false，在真实状况下，这个变量应该保存在本地sp中，跟随so的变化而改变。避免重复加载，影响性能
                initialized.set(this,false);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        super.ensureInitializationComplete(applicationContext, args);
    }
}
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1.3 注入自定义的FlutterLoader

1.3.1 纯flutter应用注入

public class MyApplication extends FlutterApplication {
    public static Application  application;
    @Override
    public void onCreate() {
        //修改FlutterLoader
        FlutterInjector flutterInjector = FlutterInjector.instance();
        try {
            Class FlutterInjectorClass = Class.forName("io.flutter.FlutterInjector");
            Field nameField = FlutterInjectorClass.getDeclaredField("flutterLoader");
            nameField.setAccessible(true);
            nameField.set(flutterInjector,KCFlutterLoader.getInstance());
        } catch (Exception e) {
            e.printStackTrace();
        }
        super.onCreate();
        application=this;
    }
}
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1.3.2 混合flutter应用注入

在混合应用中注入自定义的FlutterLoader相对简单，只须要在FlutterEngine初始化时将自定义FlutterLoader实例传递进去就行了：

FlutterEngine flutterEngine =new FlutterEngine(context, KCFlutterLoader.getInstance(),new FlutterJNI())
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1.4 libapp.so的注意

1.libapp.so为了安全性最好下载在应用的file目录下

2.libapp.so在下载完成后能够经过生成md5值，确保文件安全性和完整性

3.若是更新的libapp.so初始化完成后，为了不重复加载，须要设置FlutterLoader中的initialized为true（initialized变量保存到本地sp，跟随so的变化而改变）。
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一.经过FlutterLoader加载更新libapp.so文件完成动态化--源码解析

到这里就完成动态化方案的代码编写，至于说苹果的动态化方案，就算有大家敢用吗...，懂得都懂。谢谢了你们，划了这么多水，最后求个赞QAQ。