String sdCardDir =Environment.getExternalStorageDirectory().getAbsolutePath();
                File saveFile = new File(sdCardDir, "aaaa.txt");//new FileOutputStream(file, true);true：不覆盖写入文件
                FileOutputStream outStream = null;
                try {
                    outStream = new FileOutputStream(saveFile);
                    outStream.write(finalContent.getBytes("gbk"));//UFT-8在android不能用，只能用gbk!!!不设置的话可能会变成乱码！！！
                    outStream.close();
                    outStream.flush();
                    isSave = true;
                    Toast.makeText(PusherEndActivity.this, "文件已经保存啦！赶快去查看吧!", Toast.LENGTH_SHORT).show();
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }

btn_open_txt.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (isSave){
                
                    String path = Environment.getExternalStorageDirectory().getPath();
                    File file = new File(path);
                    Intent intent1 = new Intent(Intent.ACTION_GET_CONTENT);

                    intent1.addCategory(Intent.CATEGORY_DEFAULT);
                    intent1.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
         
                    intent1.setDataAndType(Uri.fromFile(file), "text/plain");
                    try {
                        startActivity(intent1);
                        finish();
//            startActivity(Intent.createChooser(intent,"选择浏览工具"));
                    } catch (ActivityNotFoundException e) {
                        e.printStackTrace();
                    }

                }else {
                    Toast.makeText(PusherEndActivity.this, "还没有保存文件哦！", Toast.LENGTH_SHORT).show();
                }


            }
        });