Android文档下载小工具

快来打我* 2022-04-16 03:50 262阅读 0赞

1、DownloadUtils类

public class DownloadUtils {
    
        private static ProgressDialog mDialog = null;
    
        /**
         * 显示下载进度条
         *
         * @param aty
         */
        public static void showProgressDialog(Activity aty) {
            if (mDialog == null) {
                mDialog = new ProgressDialog(aty);
                mDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);//设置风格为圆形进度条
                mDialog.setMessage(aty.getResources().getString(R.string.msg_downloading));
                mDialog.setIndeterminate(false);//设置进度条是否为不明确
                mDialog.setCancelable(true);//设置进度条是否可以按退回键取消
                mDialog.setCanceledOnTouchOutside(false);
                mDialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
                    @Override
                    public void onDismiss(DialogInterface dialog) {
                        mDialog = null;
                    }
                });
                mDialog.show();
            }
        }
    
        /**
         * 关闭下载进度条
         */
        public static void closeProgressDialog() {
            if (mDialog != null) {
                mDialog.dismiss();
                mDialog = null;
            }
        }
    
        /**
         * 获取打开文档意图
         *
         * @param file
         * @return
         */
        public static Intent getFileIntent(Activity activity, File file) {
            Uri uri = Uri.fromFile(file);
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
                //通过FileProvider创建一个content类型的Uri
                uri = FileProvider.getUriForFile(activity, "com.invt.fileprovider", file);
            }
            String type = getMIMEType(file);
            Intent intent = new Intent("android.intent.action.VIEW");
            intent.addCategory("android.intent.category.DEFAULT");
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            intent.setDataAndType(uri, type);
            return intent;
        }
    
        /**
         * 下载文件到sdcard
         *
         * @param fileName
         * @param input
         */
        public static void writeToSDCard(String fileName, InputStream input) {
            // 判断是否挂载了SD卡
            String storageState = Environment.getExternalStorageState();
            if (storageState.equals(Environment.MEDIA_MOUNTED)) {
                String directory = getDownloadPath();
                File dir = new File(directory);
                if (!dir.exists()) {
                    dir.mkdirs();
                }
                File file = new File(directory, fileName);
                if(file.exists()){
                    file.delete();
                }
                try {
                    FileOutputStream fos = new FileOutputStream(file);
                    byte[] b = new byte[2048];
                    int j = 0;
                    while ((j = input.read(b)) != -1) {
                        fos.write(b, 0, j);
                    }
                    fos.flush();
                    fos.close();
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    
        /**
         * 获取下载路径
         *
         * @return
         */
        public static String getDownloadPath() {
            String compName = AppString.getCompanyName();
            return Environment.getExternalStorageDirectory().getAbsolutePath() + "/" + compName + "/Doc/";
        }
    
        /**
         * 获取文档类型，并打开
         *
         * @param f
         * @return
         */
        private static String getMIMEType(File f) {
            String type = "";
            String fName = f.getName();
            /* 取得扩展名 */
            String end = fName.substring(fName.lastIndexOf(".") + 1, fName.length()).toLowerCase();
            /* 依扩展名的类型决定MimeType */
            if (end.equals("pdf")) {
                type = "application/pdf";
            } else if (end.equals("m4a") || end.equals("mp3") || end.equals("mid") ||
                    end.equals("xmf") || end.equals("ogg") || end.equals("wav")) {
                type = "audio/*";
            } else if (end.equals("3gp") || end.equals("mp4")) {
                type = "video/*";
            } else if (end.equals("jpg") || end.equals("gif") || end.equals("png") ||
                    end.equals("jpeg") || end.equals("bmp")) {
                type = "image/*";
            } else if (end.equals("apk")) {
                type = "application/vnd.android.package-archive";
            } else if (end.equals("pptx") || end.equals("ppt")) {
                type = "application/vnd.ms-powerpoint";
            } else if (end.equals("docx") || end.equals("doc")) {
                type = "application/vnd.ms-word";
            } else if (end.equals("xlsx") || end.equals("xls")) {
                type = "application/vnd.ms-excel";
            } else {
                //如果无法直接打开，就跳出软件列表给用户选择
                type = "*/*";
            }
            return type;
        }
    
    }

2、activity中调用

DownloaderTask task = new DownloaderTask();
            task.execute(mDownloadUrl);

/**
         * 下载使用说明
         */
        private void downloadInstructions() {
            //判断是否挂载SD卡
            if (!Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
                ToastUtils.showShortToast(this, R.string.msg_storage_nosdcard);
                return;
            }
            //获取下载的文件名
            String mDownloadUrl = "http://iot.ss.com/upload/66001-00568-SSP_V1.0.pdf";
            String fileName = mDownloadUrl.substring(mDownloadUrl.lastIndexOf("/") + 1);
            //获取文件下载路径
            String directory = DownloadUtils.getDownloadPath();
            File dir = new File(directory);
            if (dir.exists()) {
                File file = new File(directory, fileName);
                if (file.exists()) {
                    //直接打开
                    Intent intent = DownloadUtils.getFileIntent(this, file);
                    startActivity(intent);
                    return;
                }
            }
            DownloaderTask task = new DownloaderTask();
            task.execute(mDownloadUrl);
        }
    
        /**
         * 任务类
         */
        private class DownloaderTask extends AsyncTask<String, Void, String> {
    
            @Override
            protected String doInBackground(String... params) {
                String url = params[0];
                String fileName = url.substring(url.lastIndexOf("/") + 1);
                try {
                    fileName = URLDecoder.decode(fileName, "UTF-8");
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
                MyLogger.i("download", "fileName=" + fileName);
                try {
                    URL resUrl = new URL(url);
                    HttpURLConnection conn = (HttpURLConnection) resUrl.openConnection();
                    conn.connect();
                    InputStream input = conn.getInputStream();
                    DownloadUtils.writeToSDCard(fileName, input);
                    input.close();
                    return fileName;
                } catch (Exception e) {
                    e.printStackTrace();
                    return null;
                }
            }
    
            @Override
            protected void onCancelled() {
                super.onCancelled();
            }
    
            @Override
            protected void onPostExecute(String result) {
                super.onPostExecute(result);
                DownloadUtils.closeProgressDialog();
                if (result == null) {
                    ToastUtils.showShortToast(StartActivity.this, R.string.msg_downloaderror);
                    return;
                }
                ToastUtils.showShortToast(StartActivity.this, R.string.msg_downloadsuccess);
                String dir = DownloadUtils.getDownloadPath();
                File file = new File(dir, result);
                Intent intent = DownloadUtils.getFileIntent(StartActivity.this, file);
                //自动打开
                startActivity(intent);
            }
    
            @Override
            protected void onPreExecute() {
                super.onPreExecute();
                DownloadUtils.showProgressDialog(StartActivity.this);
            }
    
            @Override
            protected void onProgressUpdate(Void... values) {
                super.onProgressUpdate(values);
            }
    
        }

完！！！