Question

我有一个php脚本，如果它不存在则会创建一个文件。 php脚本在创建文件后发送该文件。现在我有一个问题，我的下载类无法下载它（我不知道为什么）当php文件正在创建一个新文件。但如果php脚本发送缓存文件，则下载有效。有没有办法让android等到php脚本执行完毕？

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;

import org.json.JSONObject;

import android.os.AsyncTask;
import android.os.Environment;
import android.os.Looper;
import android.provider.ContactsContract.Directory;
import android.util.Log;

public class DownloadMP3 extends AsyncTask<String, Integer, String> {
    private OnTaskRunning listener;
    public DownloadMP3(OnTaskRunning listener){
        this.listener=listener;
    }

    @Override
    protected String doInBackground(String... url) {
        int count;
        try {
            Log.d("Info", "create file");
            Download down = new Download();
            JSONObject jObject = new JSONObject(down.JSON(conf.d + "convert.php?v=" + url[0]));
            Log.d("Info","json file: " + jObject.get("fle"));

            URL u = new URL(conf.d + "convert.php?v=" + jObject.get("fle"));
            Log.d("Info", "dl u");
            URLConnection conexion = u.openConnection();
            Log.d("Info", "dl op");
            conexion.connect();
            Log.d("Info", "dl co");
            File directory = new File(Environment.getExternalStorageDirectory() + "/Music/VBT Splash/");
            Log.d("Info", "dl di");
            if (!directory.exists() || !directory.isDirectory()){
                directory.mkdirs();
            }



            InputStream input = new BufferedInputStream(u.openStream());

            String filename = conexion.getHeaderField("Content-Disposition");

            String file = filename.substring(filename.indexOf("\"")+1, filename.lastIndexOf("\""));

            OutputStream output = new FileOutputStream(Environment.getExternalStorageDirectory() + "/Music/VBT Splash/" + file);

            int lenghtOfFile = conexion.getContentLength();
            byte data[] = new byte[4096];

            long total = 0;

            listener.onTaskStarted();
            while ((count = input.read(data)) != -1) {
                total += count;
                output.write(data, 0, count);
                publishProgress((int) (total * 100 / lenghtOfFile));
            }
            Log.d("Info", "dl done");
            listener.onTaskDone();
            output.flush();
            output.close();
            input.close();
        } catch (Exception e) {
        }
        return null;
    }

    protected void onProgressUpdate(Integer... progress) {
        listener.onTaskProgress(progress[0]);
    }

    protected void onPostExecute(int result) {

    }
}

Answer 1

您必须将重定向传达给您的客户端代码。如果您只是点击完整的文件路径URL，并且它不存在，则不会下载它。所以相反，首先从脚本获取下载URL。（如果它不存在，将创建一个新的）然后，下载该URL。这使得总共有2个服务器请求。

等待php脚本然后下载

1 个答案: