Android项目实战（三十一）：异步下载apk文件并安装(非静默安装)

　　 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />     //文件操作权限
    <uses-permission android:name="android.permission.INTERNET" />                  //网络权限

　　　private void showDownloadProgressDialog(Context context) {
        ProgressDialog progressDialog = new ProgressDialog(context);
        progressDialog.setTitle("提示");
        progressDialog.setMessage("正在下载...");
        progressDialog.setIndeterminate(false);
        progressDialog.setMax(100);
        progressDialog.setCancelable(false);                    //设置不可点击界面之外的区域让对话框小时
        progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);         //进度条类型
        progressDialog.show();
        String downloadUrl = "http://ac-edNxPKqQ.clouddn.com/800exxxxxxx68ebcefda.apk"; //这里写你的apk url地址
        new DownloadAPK(progressDialog).execute(downloadUrl);
    }

private class DownloadAPK extends AsyncTask<String, Integer, String> {
        ProgressDialog progressDialog;
        File file;

        public DownloadAPK(ProgressDialog progressDialog) {
            this.progressDialog = progressDialog;
        }

        @Override
        protected String doInBackground(String... params) {
　　　　　　　//根据url获取网络数据生成apk文件
            return null;
        }

        @Override
        protected void onProgressUpdate(Integer... progress) {
            super.onProgressUpdate(progress);
       　　　// 这里 改变ProgressDialog的进度值 
　　　　}

        @Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
　　　　　　　//到这里说明下载完成，判断文件是否存在，如果存在，执行安装apk的操作
        }

    }

　　　　 ProgressDialog progressDialog;
        File file;

　　　　  public DownloadAPK(ProgressDialog progressDialog) {
            this.progressDialog = progressDialog;
        }

　　　　 @Override
        protected void onProgressUpdate(Integer... progress) {
            super.onProgressUpdate(progress);
            progressDialog.setProgress(progress[0]);
        }

 　　　　@Override
        protected String doInBackground(String... params) {
            URL url;
            HttpURLConnection conn;
            BufferedInputStream bis = null;
            FileOutputStream fos = null;

            try {
                url = new URL(params[0]);
                conn = (HttpURLConnection) url.openConnection();
                conn.setRequestMethod("GET");
                conn.setConnectTimeout(5000);

                int fileLength = conn.getContentLength();
                bis = new BufferedInputStream(conn.getInputStream());
                String fileName = Environment.getExternalStorageDirectory().getPath() + "/magkare/action.apk";
                file = new File(fileName);
                if (!file.exists()) {
                    if (!file.getParentFile().exists()) {
                        file.getParentFile().mkdirs();
                    }
                    file.createNewFile();
                }
                fos = new FileOutputStream(file);
                byte data[] = new byte[4 * 1024];
                long total = 0;
                int count;
                while ((count = bis.read(data)) != -1) {
                    total += count;
                    publishProgress((int) (total * 100 / fileLength));
                    fos.write(data, 0, count);
                    fos.flush();
                }
                fos.flush();

            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    if (fos != null) {
                        fos.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
                try {
                    if (bis != null) {
                        bis.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            return null;
        }

　　　　@Override
        protected void onPostExecute(String s) {
            super.onPostExecute(s);
            openFile(file);                 //打开安装apk文件操作
            progressDialog.dismiss();　　    //关闭对话框
        }

　　　　　private void openFile(File file) {
            if (file!=null){
                Intent intent = new Intent(Intent.ACTION_VIEW);
                intent.setDataAndType(Uri.fromFile(file), "application/vnd.android.package-archive");
                TaskListActivity.this.startActivity(intent);
            }
        }