无法从JSON网址下载图像. [英] Download image from JSON url is not working.

问题描述

当我插入sdcard时，它的工作原理.

When i insert sdcard its working.

如何将其保存到内部存储中?

How can i save it to my internal storage?

我从Url下载了图像，并希望在sd卡插入显示为确定后将其显示在我的手机中.
但是我的三星银河S6 edge plus没有SD卡，因此无法下载图像.如何将图像保存到内部存储中，而不是外部存储中.

i downloaded image from Url and want to show it to my phone when sd card inserted it showing Ok.
but my Samsung galaxy S6 edge plus have no Sdcard so image cant be downloaded.how can i save the image into internal storage instead of external storage.

package com.example.makdia.tuntuninews;

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

import android.app.Activity;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.content.Intent;
import android.graphics.drawable.Drawable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;

public class ViewImage extends AppCompatActivity {


    Button btnShowProgress;
    String _id;
    // Progress Dialog
    private ProgressDialog pDialog;
    ImageView my_image;
    // Progress dialog type (0 - for Horizontal progress bar)
    public static final int progress_bar_type = 0;
    String _photo;
    // File url to download
    public static String file_url;

    TextView id, name;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_image);

        id = (TextView) findViewById(R.id.photoid);
        name = (TextView) findViewById(R.id.photoname);


        _id = getIntent().getStringExtra("MyID");
        file_url = getIntent().getStringExtra("MyPhoto");
        final String _name = getIntent().getStringExtra("MyName");

        id.setText("PhotoID = "+_id);
        name.setText("PhotoName = "+_name +" "+file_url+ "\n\n");


        btnShowProgress = (Button) findViewById(R.id.btnProgressBar);
        // Image view to show image after downloading
        my_image = (ImageView) findViewById(R.id.my_image);
        /**
         * Show Progress bar click event
         * */
        btnShowProgress.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // starting new Async Task
                new DownloadFileFromURL().execute(file_url);
            }
        });



    }

    /**
     * Showing Dialog
     * */
    @Override
    protected Dialog onCreateDialog(int id) {
        switch (id) {
            case progress_bar_type: // we set this to 0
                pDialog = new ProgressDialog(this);
                pDialog.setMessage("Downloading file. Please wait...");
                pDialog.setIndeterminate(false);
                pDialog.setMax(100);
                pDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
                pDialog.setCancelable(true);
                pDialog.show();
                return pDialog;
            default:
                return null;
        }
    }

    /**
     * Background Async Task to download file
     * */
    class DownloadFileFromURL extends AsyncTask<String, String, String> {

        /**
         * Before starting background thread
         * Show Progress Bar Dialog
         * */
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            showDialog(progress_bar_type);
        }

        /**
         * Downloading file in background thread
         * */
        @Override
        protected String doInBackground(String... f_url) {
            int count;
            try {
                URL url = new URL(f_url[0]);
                URLConnection conection = url.openConnection();
                conection.connect();
                // this will be useful so that you can show a tipical 0-100% progress bar
                int lenghtOfFile = conection.getContentLength();

                // download the file
                InputStream input = new BufferedInputStream(url.openStream(), 8192);

                // Output stream
                OutputStream output = new FileOutputStream("/sdcard/"+_id+".jpg");

                byte data[] = new byte[1024];

                long total = 0;

                while ((count = input.read(data)) != -1) {
                    total += count;
                    // publishing the progress....
                    // After this onProgressUpdate will be called
                    publishProgress(""+(int)((total*100)/lenghtOfFile));

                    // writing data to file
                    output.write(data, 0, count);
                }

                // flushing output
                output.flush();

                // closing streams
                output.close();
                input.close();

            } catch (Exception e) {
                Log.e("Error: ", e.getMessage());
            }

            return null;
        }

        /**
         * Updating progress bar
         * */
        protected void onProgressUpdate(String... progress) {
            // setting progress percentage
            pDialog.setProgress(Integer.parseInt(progress[0]));
        }

        /**
         * After completing background task
         * Dismiss the progress dialog
         * **/
        @Override
        protected void onPostExecute(String file_url) {
            // dismiss the dialog after the file was downloaded
            dismissDialog(progress_bar_type);

            // Displaying downloaded image into image view
            // Reading image path from sdcard
            String imagePath = Environment.getExternalStorageDirectory().toString() +"/"+_id+".jpg";
            // setting downloaded into image view
            my_image.setImageDrawable(Drawable.createFromPath(imagePath));
        }

    }



}

推荐答案

替换:

OutputStream output = new FileOutputStream("/sdcard/"+_id+".jpg");

使用:

FileOutputStream outputStream = openFileOutput(_id+".jpg", Context.MODE_PRIVATE);

注意:在保存文件之前，为存储添加运行时权限.希望这会有所帮助.

NB: Add Run-time Permission for Storage before saving file. Hope this helps.

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