在处理来自 API 的数据时等待调用 Intent

Question

我在尝试阻止 Activity 的意图发生时遇到问题，直到 API 调用被消耗和处理。我有一个按钮，单击该按钮将调用两种方法。第一个方法 'gatherResponceAndProcess' 获取响应，导入数据，并将其转换为一些新对象。这部分正在工作。但是，在 gatherResponceAndProcess 完成之前调用 moveToNextActivity。我尝试了各种各样的事情，但无济于事。我不知道在哪里或需要做什么。请帮忙。

public class MainActivity extends AppCompatActivity {...
 ...
        Button.setOnClickListener(v -> {
            gatherResponceAndProcess();  // <<<<<<< CALLS API AND IMPORTS DATA
            moveToNextActivity();
    });

  private void gatherResponceAndProcess() {

        try {
            Helper helper = new Helper(buildURL());
            helper.fetchAndProcess();
        }
        catch (Exception e) {
            e.printStackTrace();
            Toast.makeText(MainActivity.this, R.string.error, Toast.LENGTH_SHORT).show();
        }
   }

    private void moveToNextActivity() {

        Intent intent = new Intent(mContext, NextActivity.class);
        Log.d(TAG, "moveToNextActivity: Creating Intent");
        mContext.startActivity(intent);
   }
...

public class Helper implements APICall.AsyncResponse {...
...
   public void fetchUsersObservations() {

    APICall call = new APICall(URL);
    call.execute(); //Calls processFinish() when finsished 
   }

   @Override
   public void processFinish(JSONArray results) {//THIS HAS TO FINISH BEFORE moveToNextActivity() SHOULD BE CALLED
    //map json to classes
     arrayOfClasses(oldClasses)
    //massage the data
    arrayOfNewClasses.add(massagedData)
    MyNewClass.importMassagedData(arrayOfNewClasses); //NextActivity Needs this
   }
...

public class APICall extends AsyncTask {...
...
URL APIUrl;
int page = 1;
private Helper helper = Helper();

public INatCall(URL url) {
    this.iNatUrl = url;
}

@Override
protected Object doInBackground(Object[] objects) {

    return restCall(APIUrl);//Returns JSONObject

}

@Override
protected void onPostExecute(Object o) {
    helper.processFinish((JSONArray) o)
}

Answer 1

我最后做的是调用 moveToNextActivity();来自 Helper.processFinish。这不是理想的，因为我必须传递上下文。

public class MainActivity extends AppCompatActivity {...
 ...
        Button.setOnClickListener(v -> {
            gatherResponceAndProcess();  // <<<<<<< CALLS API AND IMPORTS DATA
            //moveToNextActivity(); <--Removed
    });

  private void gatherResponceAndProcess() {

        try {
            Helper helper = new Helper(buildURL());
            helper.fetchAndProcess(mContext);
        }
        catch (Exception e) {
            e.printStackTrace();
            Toast.makeText(MainActivity.this, R.string.error, Toast.LENGTH_SHORT).show();
        }
   }

    private void moveToNextActivity(Context context) {

        Intent intent = new Intent(context, NextActivity.class);
        Log.d(TAG, "moveToNextActivity: Creating Intent");
        context.startActivity(intent);
   }
...


public class Helper implements APICall.AsyncResponse {...
...
   public void fetchUsersObservations(Context context) {

    APICall call = new APICall(URL);
    call.execute(); //Calls processFinish() when finsished 
   }

   @Override
   public void processFinish(JSONArray results) {//THIS HAS TO FINISH BEFORE moveToNextActivity() SHOULD BE CALLED
    //map json to classes
     arrayOfClasses(oldClasses)
    //massage the data
    arrayOfNewClasses.add(massagedData)
    MyNewClass.importMassagedData(arrayOfNewClasses); //NextActivity Needs this
    moveToNextActivity(mContext); //<-- Added Here
   }
...

在处理来自 API 的数据时等待调用 Intent

Wait to call Intent while Processing data from API

java

android

wait

async-await