java - 使用android intent从服务器打开pdf文件

Question

我正在网上搜索如何使用 Android 上的默认 pdf 查看器从服务器打开 pdf 文件。我发现的是先下载文件，然后有意启动它或使用 google 文档加载它。我不想做所有这些。我只想在手机的默认 pdf 查看器中直接从服务器加载它。我试过有意地打开视频网址并且它有效。但是有意打开 pdf url 是行不通的。下面是我的代码；

private void openFilePDF(){
        try{
            Toast.makeText(getBaseContext(), "Opening PDF... ", Toast.LENGTH_SHORT).show();
            Intent inte = new Intent(Intent.ACTION_VIEW);
            inte.setDataAndType(
                    Uri.parse("http://122.248.233.68/pvfiles/Guide-2.pdf"),
                    "application/pdf");

            startActivity(inte);
            }catch(ActivityNotFoundException e){
                Log.e("Viewer not installed on your device.", e.getMessage());
            }
    }

有什么方法可以在 Intent 中加载 pdf url 吗？

Answer 1

首先创建一个下载器类

public class Downloader {

    public static void DownloadFile(String fileURL, File directory) {
        try {

            FileOutputStream f = new FileOutputStream(directory);
            URL u = new URL(fileURL);
            HttpURLConnection c = (HttpURLConnection) u.openConnection();
            c.setRequestMethod("GET");
            c.setDoOutput(true);
            c.connect();

            InputStream in = c.getInputStream();

            byte[] buffer = new byte[1024];
            int len1 = 0;
            while ((len1 = in.read(buffer)) > 0) {
                f.write(buffer, 0, len1);
            }
            f.close();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

之后创建一个从互联网下载 PDF 文件的 Activity ，

public class MainActivity extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        String extStorageDirectory = Environment.getExternalStorageDirectory()
        .toString();
        File folder = new File(extStorageDirectory, "pdf");
        folder.mkdir();
        File file = new File(folder, "Read.pdf");
        try {
            file.createNewFile();
        } catch (IOException e1) {
            e1.printStackTrace();
        }
        Downloader.DownloadFile("http://122.248.233.68/pvfiles/Guide-2.pdf", file);

        showPdf();
    }
    public void showPdf()
        {
            File file = new File(Environment.getExternalStorageDirectory()+"/Mypdf/Read.pdf");
            PackageManager packageManager = getPackageManager();
            Intent testIntent = new Intent(Intent.ACTION_VIEW);
            testIntent.setType("application/pdf");
            List list = packageManager.queryIntentActivities(testIntent, PackageManager.MATCH_DEFAULT_ONLY);
            Intent intent = new Intent();
            intent.setAction(Intent.ACTION_VIEW);
            Uri uri = Uri.fromFile(file);
            intent.setDataAndType(uri, "application/pdf");
            startActivity(intent);
        }
}

最后在 AndroidManifest.xml 中声明权限

<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>