从服务器自动下载图像

Question

如何在不按Android Studio按钮的情况下从服务器下载图像。代码运行正常，但只有按下按钮才能下载。如何自动下载图像

@覆盖     public void onClick（查看视图）{         switch（view.getId（））{             case R.id.bDownloadImage：                 new DonwloadImage（downloadImageName.getText（）。toString（））。execute（）;                 打破;         }     }

private class DonwloadImage extends AsyncTask<Void, Void, Bitmap> {
    String name;
    ProgressDialog loading;
    public DonwloadImage (String name){//constractor
        this.name = name;
    }

    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        mProgressDialog = new ProgressDialog(Receiver.this);
        mProgressDialog.setTitle("Downloading Image");   // title of progress dialog
        mProgressDialog.setMessage("Loading...");    // message displaying
        mProgressDialog.setIndeterminate(false);
        mProgressDialog.show();    // show method
    }


    @Override
    protected Bitmap doInBackground(Void... voids) {
        // loading.dismiss();
        String url = SERVER_ADDRESS + "pictures/" + name + ".JPG";
        try
        {
            URLConnection connection = new URL(url).openConnection();
            connection.setConnectTimeout(1000 * 30);
            connection.setReadTimeout(1000 * 30);

            return BitmapFactory.decodeStream((InputStream) connection.getContent(), null, null);
        }
        catch (Exception e)
        {
            e.printStackTrace();
            return null;
        }
    }


    @Override
    protected void onPostExecute(Bitmap bitmap)
    {
        super.onPostExecute(bitmap);
        if(bitmap != null)
        {
            downloadImage.setImageBitmap(bitmap);
            mProgressDialog.dismiss();
        }
    }
}

Answer 1

你应该添加

DonwloadImage(downloadImageName.getText().toString()).execute();

在onCreate of Activity中，用于autoDownload属性。