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Java Android应用程序使用OnCreateOptions功能表的速度越来越慢_Java_Android - Fatal编程技术网

Java Android应用程序使用OnCreateOptions功能表的速度越来越慢

Java Android应用程序使用OnCreateOptions功能表的速度越来越慢,java,android,Java,Android,我的应用程序在列表视图中显示所有图像。速度很快,但后来我添加了oncreateoptions菜单。从那时起,该应用程序速度非常慢,只显示一幅图像。这与线程有关吗 这是我的main活动代码: public class MainActivity extends AppCompatActivity { static ArrayList<Product> arrayList; ListView lv; @Override protected void onCreate(B

我的应用程序在
列表视图中显示所有图像。速度很快,但后来我添加了
oncreateoptions菜单
。从那时起,该应用程序速度非常慢,只显示一幅图像。这与线程有关吗

这是我的
main活动代码

public class MainActivity extends AppCompatActivity {

  static ArrayList<Product> arrayList;
  ListView lv;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);

      arrayList = new ArrayList<>();
      lv = (ListView) findViewById(R.id.listView);

      runOnUiThread(new Runnable() {
         @Override
         public void run() {
            new ReadJSON().execute("http://10.0.3.2:5000/products/id/6");
          }
      });
  }

  class ReadJSON extends AsyncTask<String, Integer, String> {

      @Override
      protected String doInBackground(String... params) {
          return readURL(params[0]);
      }

      @Override
      protected void onPostExecute(String content) {
          try {
              JSONObject jsonObject = new JSONObject(content);
              JSONArray jsonArray =  jsonObject.getJSONArray("products");

              for(int i =0;i<jsonArray.length(); i++){
                  JSONObject productObject = jsonArray.getJSONObject(i);
                  arrayList.add(new Product(
                          productObject.getString("image"),
                          productObject.getString("title"),
                          productObject.getString("price"),
                          productObject.getString("description")
                  ));
              }
          } catch (JSONException e) {
              e.printStackTrace();
          }
          CustomListAdapter adapter = new CustomListAdapter(
                  getApplicationContext(), R.layout.custom_list_layout, arrayList
          );
          lv.setAdapter(adapter);

          lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {  // list item click opens a new detailed activity
              @Override
              public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                    Product product = arrayList.get(position); // getting the model
                  Intent intent = new Intent(MainActivity.this, DetailActivity.class);
                  intent.putExtra("title", product.getName());
                  intent.putExtra("price", product.getPrice());
                  intent.putExtra("img", product.getImage());
                  intent.putExtra("description", product.getDescription());
                  intent.putExtra(ShoppingCartHelper.PRODUCT_INDEX, position);
                  startActivity(intent);
              }
          });
      }
  }

  private static String readURL(String theUrl) {
      StringBuilder content = new StringBuilder();
      try {
          // create a url object
          URL url = new URL(theUrl);
          // create a urlconnection object
          URLConnection urlConnection = url.openConnection();
          // wrap the urlconnection in a bufferedreader
          BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
          String line;
          // read from the urlconnection via the bufferedreader
          while ((line = bufferedReader.readLine()) != null) {
              content.append(line + "\n");
          }
          bufferedReader.close();
      } catch (Exception e) {
          e.printStackTrace();
      }
      return content.toString();
  }

  public static ArrayList<Product> getProduct(Resources res) {
      return arrayList;
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {

      MenuInflater inflater = getMenuInflater();
      inflater.inflate(R.menu.menu, menu);

      return true;
  }

  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
      int id = item.getItemId();
      if(id == R.id.shoppingcart) {
          Intent viewShoppingCartIntent = new Intent(getBaseContext(), ShoppingCartActivity.class);
          startActivity(viewShoppingCartIntent);
          return true;
      }

      return super.onOptionsItemSelected(item);
  }

}

您没有在创建选项菜单中执行任何繁重的操作,因此我看不出有任何问题

但是在
runOnUiThread
内部运行
AsyncTask
不是一个好主意<代码>异步任务
本身已经处理哪些代码在单独的线程上运行,哪些代码在UI线程上运行

onCreate
中调用它,如下所示:

new ReadJSON().execute("http://10.0.3.2:5000/products/all");

在runOnUiThread中运行异步任务不是一个好主意。异步任务本身已经处理哪些代码在单独的线程上运行,哪些代码在UI线程上运行。
public class MainActivity extends AppCompatActivity {
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
  }

  public boolean onCreateOptionsMenu(Menu menu) {

    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.menu, menu);

    return true;
  }

  @Override
  public boolean onOptionsItemSelected(MenuItem item) {
    int id = item.getItemId();
    if(id == R.id.shoppingcart) {
        Intent viewShoppingCartIntent = new Intent(getBaseContext(), ShoppingCartActivity.class);
        startActivity(viewShoppingCartIntent);
        return true;
    }

    return super.onOptionsItemSelected(item);
  }
}
new ReadJSON().execute("http://10.0.3.2:5000/products/all");