java - 如何避免应用程序可能在其主线程上做太多工作

Question

我有两个类。一个是我的 SettingsActivity 和一个由我的 volley 完成工作的类。在我的网络服务中，它有大量数据需要转换为 ArrayList 并将其保存到我的数据库中；我有两个 Web 服务要在第一个服务完成后调用，第二个服务启动之前会延迟 1 秒。在这些事情之后，它在我的日志中总是显示以下内容

 I/Choreographer: Skipped 226 frames!  The application may be doing too much work on its main thread.
 V/RenderScript: 0x5595d9d0e0 Launching thread(s), CPUs 8
 W/art: Suspending all threads took: 20.500ms
 W/SQLiteConnectionPool: A SQLiteConnection object for database '/data/data/com.app.myapp/databases/myDB.sqlite' was leaked!  Please fix your application to end transactions in progress properly and to close the database when it is no longer needed.
 I/art: Background partial concurrent mark sweep GC freed 38249(2025KB) AllocSpace objects, 2(968KB) LOS objects, 40% free, 16MB/26MB, paused 569us total 130.628ms
 I/Choreographer: Skipped 1528 frames!  The application may be doing too much work on its main thread.

我已经检查我的数据库在使用后是否关闭，并且所有数据库都已关闭。但我仍然收到数据库泄露消息和跳过了xxx帧。我已经尝试创建一个新线程，在为我的 Volley 调用 class 时，在我的 SettingsActivity 中调用我的类，例如

   btnSync.setOnClickListener(new View.OnClickListener(){
        public void onClick(View v) {

  Thread thread = new Thread(new Runnable(){
                @Override
                public void run(){
                    Parameter.parameterOneVolley(SettingsActivity.this, getApplicationContext());
                }
            });
    }
    });

尝试此操作后，我遇到无法在未调用 Looper.prepare() 的线程内创建处理程序

然后也尝试使用这个

 runOnUiThread(new Runnable() {

                @Override
                public void run() {
                    Parameter.parameterOneVolley(SettingsActivity.this, getApplicationContext());
                }
            });

但是我收到一条消息跳过帧。怎么解决呢？预先非常感谢您的帮助。

在我的 Paramater 类中，我还调用 ProgressDialog。

这是我的Paramter.parameterOneVolley代码

public static void parameterOneVolley(final Activity activity, final Context context) {

    final ProgressDialog pd = new ProgressDialog(activity);
    pd.setMessage("Fetching data....");
    pd.show();

    initializeDatabase(context);
    sqLiteAdapter = new SQLiteAdapter(activity);

    regionList = new ArrayList<Region>();
    divisionList = new ArrayList<Division>();


    final Response.Listener<JSONObject> listener = new Response.Listener<JSONObject>() {
        @Override
        public void onResponse(JSONObject response) {

            try {

                JSONArray regionArr = response.getJSONArray("Region");
                JSONArray divisionArr = response.getJSONArray("Division");

                sqLiteAdapter.openToRead();



                    for(int i = 0; i < regionArr.length(); i++){
                        JSONObject regionObj = (JSONObject) regionArr.get(i);
                        Region region = new Region(regionObj.getInt("RegionId"),regionObj.getString("Region"));

                        regionList.add(region);


                    if(regionList.size()!=0) {
                        sqLiteAdapter.insertOrReplaceRegion(regionList);
                    }
                }


                    for(int i = 0; i < divisionArr.length(); i++){
                        JSONObject divisionObj = (JSONObject) divisionArr.get(i);
                        Division division = new Division(divisionObj.getInt("RegionId"),divisionObj.getInt("DivisionId"),divisionObj.getString("Division"));

                        divisionList.add(division);


                    if(divisionList.size()!=0) { sqLiteAdapter.insertOrReplaceDivision(divisionList);
                    }
                }

                sqLiteAdapter.close();

                if(pd != null && pd.isShowing()) {
                    pd.dismiss();
                }

            } catch (JSONException e) {
                e.printStackTrace();
                sqLiteAdapter.close();

                if(pd != null && pd.isShowing()) {
                    pd.dismiss();
                }

                Toast.makeText(context,
                        e.getMessage(), Toast.LENGTH_SHORT).show();
            }


            Toast.makeText(context, "Successfully synced.", Toast.LENGTH_SHORT).show();
                   //call next web service
                    final Handler handler = new Handler();
                    handler.postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            parameterTwoVolley(activity, context);
                    }
                    }, 1000);

        }
    };

    final Response.ErrorListener errorListener = new Response.ErrorListener() {
        @Override
        public void onErrorResponse(VolleyError error) {
            if(pd != null && pd.isShowing()) {
                    pd.dismiss();
                }

            if (error.networkResponse != null) {
                Log.d(TAG, "Error Response code: " + error.networkResponse.statusCode);
                Toast.makeText(context, error.networkResponse.statusCode, Toast.LENGTH_SHORT).show();
            }
            if (error instanceof TimeoutError || error instanceof NoConnectionError) {
                Log.d(TAG, "Error Response code: Timeout/NoConnection");
                Toast.makeText(context, "Timeout/NoConnection", Toast.LENGTH_SHORT).show();
            } else if (error instanceof AuthFailureError) {
                Log.d(TAG, "Error Response code: AuthFailureError");
                Toast.makeText(context, "AuthFailureError", Toast.LENGTH_SHORT).show();
            } else if (error instanceof ServerError) {
                Log.d(TAG, "Error Response code: ServerError");
                Toast.makeText(context, "ServerError", Toast.LENGTH_SHORT).show();
            } else if (error instanceof NetworkError) {
                Log.d(TAG, "Error Response code: NetworkError");
                Toast.makeText(context, "NetworkError", Toast.LENGTH_SHORT).show();
            } else if (error instanceof ParseError) {
                Log.d(TAG, "Error Response code: ParseError");
                Toast.makeText(context, "ParseError", Toast.LENGTH_SHORT).show();
            }

            if(pd != null && pd.isShowing()) {
                pd.dismiss();
            }
        }
    };
}

<小时/>

我尝试添加

activity.runOnUiThread(new Runnable() {

                @Override
                public void run() {
                    pd = new ProgressDialog(activity);
            pd.setMessage("Fetching data....");
            pd.show();
        }
                }
            });

activity.runOnUiThread(new Runnable() {

                @Override
                public void run() {
                    if(pd != null && pd.isShowing()) {
                        pd.dismiss();
                    }
                    Toast.makeText(context, "Successfully synced.", Toast.LENGTH_SHORT).show();
                }
            });

每次我使用进度对话框和Toast，但我仍然遇到跳过帧

还尝试使用 ProgressBar 来代替并显示和隐藏它，但仍然遇到跳帧

Answer 1

在 Android 中，只有主线程(也称为 UI 线程)可以更新 View 。这是因为在 Android 中，UI 工具包不是线程安全的。

当您尝试从工作线程更新 UI 时，Android 会抛出此异常。如果您想从另一个线程更新 UI，请使用 Handler。

final Handler handler=new Handler();
new Thread(new Runnable() {
    @Override
    public void run() {
       //your code
        handler.post(new Runnable() {
            @Override
            public void run() {
                 Parameter.parameterOneVolley(SettingsActivity.this, getApplicationContext());
            }
        });
    }
}).start();