Question

我执行异步任务时出现黑屏。应用程序显示需要30-40秒。直到那时有一个黑屏，我怎么能解决它？我看到需要很长时间的主要方法是从亚马逊S3下载对象并解压缩。

//AsyncTasks 2
class secondAsyncTask extends AsyncTask<String, String, Boolean> {
    Data newData = null;
    public String LOCAL_PATH = null;

    public secondAsyncTask(Data data) {
        newData = data;
        LOCAL_PATH = newData.context.getFilesDir().getPath().toString() ;
    }

    @Override
    protected Boolean doInBackground(String... params) {

    String fileName = newData.versionString + "_" + newData.timestampValue ;

    String KEY = fileName+ ".js" ;
    String KEY_ZIP = fileName + ".zip" ;
    String BUCKET_NAME = "galateajs" ;

    CognitoCachingCredentialsProvider credentialsProvider = new CognitoCachingCredentialsProvider(
            newData.context,
            "eu-west-1:3ad5de52-dfab-439f-96b1-8ebda", // Identity Pool ID
            Regions.EU_WEST_1 // Region
    );

    AmazonS3Client s3Client = new AmazonS3Client(credentialsProvider);

    File localFile = new File(LOCAL_PATH +"/dataFile.txt");
    File localFile_zip = new File(LOCAL_PATH +"/images.zip");

    //###
    // write to file
    try {
        ObjectMetadata object = s3Client.getObject(new GetObjectRequest(BUCKET_NAME, KEY), localFile);

        try {
            newData.setPrefrence("timestamp", newData.timestampValue);//set new timestamp
            JSONObject objTmp = newData.readFromFile("dataFile.txt");// get new local file
            newData.updateJsonString(objTmp.toString());//update global var
        } catch (Exception e) {
            e.printStackTrace();
        }

        newData.deleteImages(LOCAL_PATH + "/");
        newData.logFiles(LOCAL_PATH + "/");

        //download images
        ObjectMetadata object_zip = s3Client.getObject(new GetObjectRequest(BUCKET_NAME, KEY_ZIP), localFile_zip);
        System.out.println("File Downloaded:    " + object_zip);
        newData.unpackZip(LOCAL_PATH + "/", "images.zip");

    } catch (AmazonServiceException e) {
        System.out.println("Error Message:    " + e.getMessage());
        System.out.println("HTTP Status Code: " + e.getStatusCode());
        System.out.println("AWS Error Code:   " + e.getErrorCode());
        e.printStackTrace();
    }
    return null;
}

@Override
protected void onPostExecute(Boolean aBoolean) {
    try {

        JSONObject objTmp = newData.readFromFile("dataFile.txt");
        newData.updateJsonString(objTmp.toString());

        Splash.notificationManager.cancel(Splash.notifyId);
        Toast.makeText(Splash.context,"Boat Saver data updated successfully!",Toast.LENGTH_LONG).show();

    } catch (JSONException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }

    super.onPostExecute(aBoolean);
}

我该如何解决这个问题？

为什么我在Android上的Async任务下载exec上出现黑屏？

0 个答案: