android ，LoaderManager.LoaderCallbacks与AsyncTaskLoader， Java（2）

系统管理员 2023-09-25 17:03 93阅读 0赞

## android ，LoaderManager.LoaderCallbacks与AsyncTaskLoader， Java（2） ##

##  ##

import androidx.annotation.NonNull;
    import androidx.annotation.Nullable;
    import androidx.appcompat.app.AppCompatActivity;
    import androidx.loader.app.LoaderManager;
    import androidx.loader.content.AsyncTaskLoader;
    import androidx.loader.content.Loader;
    
    import android.content.Context;
    import android.os.Bundle;
    import android.util.Log;
    
    public class MainActivity extends AppCompatActivity {
        private static String TAG = "fly";
    
        private LoaderManager loaderManager;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
    
            loaderManager = LoaderManager.getInstance(this);
            loaderManager.initLoader(2023, new Bundle(), loaderCallbacks);
            loaderManager.initLoader(2024, new Bundle(), loaderCallbacks);
        }
    
        private LoaderManager.LoaderCallbacks loaderCallbacks = new LoaderManager.LoaderCallbacks<User>() {
            @NonNull
            @Override
            public MyLoader onCreateLoader(int id, @Nullable Bundle args) {
                Log.d(TAG, "onCreateLoader- id - " + id);
                MyLoader loader = new MyLoader(getApplicationContext());
                return loader;
            }
    
            @Override
            public void onLoadFinished(@NonNull Loader loader, User user) {
                Log.d(TAG, "onLoadFinished- " + loader.getId() + " - " + user);
            }
    
            @Override
            public void onLoaderReset(@NonNull Loader loader) {
    
            }
        };
    
        @Override
        protected void onStart() {
            super.onStart();
            Log.d(TAG, "onStart");
        }
    
        @Override
        protected void onResume() {
            super.onResume();
            Log.d(TAG, "---");
            Log.d(TAG, "onResume");
        }
    
        @Override
        protected void onStop() {
            super.onStop();
            Log.d(TAG, "onStop");
        }
    
        private static class MyLoader extends AsyncTaskLoader<User> {
            public MyLoader(@NonNull Context context) {
                super(context);
            }
    
            @Override
            protected void onStartLoading() {
                super.onStartLoading();
                Log.d(TAG, "onStartLoading- " + getId());
    
                this.forceLoad();//如果没有，则不会触发loadInBackground
            }
    
            //work thread
            @Nullable
            @Override
            public User loadInBackground() {
                User user = new User();
                user.time = System.currentTimeMillis();
                user.name = "zhangphil";
                return user;
            }
    
            //UI main thread
            @Override
            public void deliverResult(@Nullable User user) {
                super.deliverResult(user);
                Log.d(TAG, "deliverResult- " + getId() + " " + user);
            }
    
            @Override
            public void onContentChanged() {
                super.onContentChanged();
                Log.d(TAG, "onContentChanged- " + getId());
            }
        }
    
        private static class User {
            public String name;
            public long time;
    
            @Override
            public String toString() {
                return "User{" +
                        "name='" + name + '\'' +
                        ", time=" + time +
                        '}';
            }
        }
    }

输出：

![3886d4fd3e2b4ee7af03a78b91d3ad5f.png][]

[android LoaderManager与AsyncTaskLoader,java（1）\_zhangphil的博客-CSDN博客android LoaderManager与AsyncTaskLoader,java（1）![favicon32.ico][]https://blog.csdn.net/zhangphil/article/details/129622307][android LoaderManager_AsyncTaskLoader_java_1_zhangphil_-CSDN_android LoaderManager_AsyncTaskLoader_java_1_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_129622307]

[https://zhangphil.blog.csdn.net/article/details/129582389![icon-default.png_t_N2N8][]https://zhangphil.blog.csdn.net/article/details/129582389][https_zhangphil.blog.csdn.net_article_details_129582389_icon-default.png_t_N2N8_https_zhangphil.blog.csdn.net_article_details_129582389]

[3886d4fd3e2b4ee7af03a78b91d3ad5f.png]: https://img-blog.csdnimg.cn/3886d4fd3e2b4ee7af03a78b91d3ad5f.png
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[android LoaderManager_AsyncTaskLoader_java_1_zhangphil_-CSDN_android LoaderManager_AsyncTaskLoader_java_1_favicon32.ico_https_blog.csdn.net_zhangphil_article_details_129622307]: https://blog.csdn.net/zhangphil/article/details/129622307
[icon-default.png_t_N2N8]: https://csdnimg.cn/release/blog_editor_html/release2.2.4/ckeditor/plugins/CsdnLink/icons/icon-default.png?t=N2N8
[https_zhangphil.blog.csdn.net_article_details_129582389_icon-default.png_t_N2N8_https_zhangphil.blog.csdn.net_article_details_129582389]: https://zhangphil.blog.csdn.net/article/details/129582389