问题描述
我正在尝试显示存储在我的Android应用程序资产文件夹中的"NEFT.pdf"文件.
以下代码在API 25之前绝对可以正常工作
I am trying to display "NEFT.pdf" file stored in the asset folder of my android app.
The following code works absolutely fine till API 25
private void CopyReadAssets(String filename) {
AssetManager assetManager = getAssets();
InputStream in = null;
OutputStream out = null;
File file = new File(getFilesDir(), filename);
try {
in = assetManager.open(filename);
out = openFileOutput(file.getName(), Context.MODE_WORLD_READABLE);
copyFile(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(
Uri.parse("file://" + getFilesDir() + "/"+filename), "application/pdf");
startActivity(intent);
} catch (Exception e)
{
Toast.makeText(PdfFilesList.this, "cra: "+e.toString(), Toast.LENGTH_SHORT).show();
}
}
此代码不适用于API 25及更高版本.它给出错误 MODE_WORLD_READABLE 不再受支持的错误.
我将其更改为 MODE_PRIVATE ,但这又给了我另一个错误
This code does not work on API 25 and above. It gives the error MODE_WORLD_READABLE no longer supported.
I changed it to MODE_PRIVATE but that gives me another error
通过intent.getdata()在应用程序之外公开的android.os.fileuriexposedException.
因此,我采用了 Developer.Android中解释的概念. com .
这是我在错误日志中得到的内容:
E/DisplayData:openFd:java.io.FileNotFoundException:没有此类文件或目录
E/PdfLoader:无法加载文件(无法打开)显示数据[PDF:NEFT.pdf] + ContentOpenable,uri:content://com.user.plansmart.provider/pdf_files/NEFT .pdf
uri对我来说似乎正确.任何人都可以帮助我在这里找到错误.
这是清单文件中的 provider 元素.
android.os.fileuriexposedexception exposed beyond app through intent.getdata().
So I applied the concept explained at Developer.Android.com.
This is what I get in the error log:
E/DisplayData: openFd: java.io.FileNotFoundException: No such file or directory
E/PdfLoader: Can't load file (doesn't open) Display Data [PDF : NEFT.pdf] +ContentOpenable, uri: content://com.user.plansmart.provider/pdf_files/NEFT.pdf
uri looks correct to me. Can Anyone help me in locating the error here.
Here is the provider element in the manifest file.
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="${applicationId}.provider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/provider_paths"/>
</provider>
这是 provider_paths.xml 文件
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
<external-path name="external_files" path="."/>
<files-path name="pdf_files" path="pdf/"/>
这是显示pdf文件的Android代码
This is the Android code to display the pdf file
private void displayFile(String filename) {
try {
File filePath = new File(getApplicationContext().getFilesDir(), "pdf");
File newFile = new File(filePath, filename);
//new version
Uri fileUri = FileProvider.getUriForFile(PdfFilesList.this,
BuildConfig.APPLICATION_ID + ".provider", newFile);
getApplicationContext().grantUriPermission(PACKAGE_NAME,
fileUri, Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(fileUri, "application/pdf");
intent.setFlags(FLAG_GRANT_READ_URI_PERMISSION | FLAG_GRANT_WRITE_URI_PERMISSION);
startActivity(intent);
}catch (Exception e){
e.printStackTrace();
Toast.makeText(PdfFilesList.this, "df "+e.toString(), Toast.LENGTH_SHORT).show();
}
}
推荐答案
因为您想在单独的应用程序(例如Adobe Reader)中显示PDF文件,所以我希望执行以下操作:-
Cause you wanna display the PDF file in a separate application (such as Adobe Reader), I would prefer doing the following:-
private void CopyReadAssets()
{
AssetManager assetManager = getActivity().getAssets();
InputStream in = null;
OutputStream out = null;
String state = Environment.getExternalStorageState();
if (!Environment.MEDIA_MOUNTED.equals(state)) {
Toast.makeText(getActivity(), "External Storage is not Available", Toast.LENGTH_SHORT).show();
}
File pdfDir = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/PDFs");
if (!pdfDir.exists()) {
pdfDir.mkdir();
}
File file = new File(pdfDir + "/abc.pdf");
try
{
in = assetManager.open("abc.pdf");
out = new BufferedOutputStream(new FileOutputStream(file));
copyFile(in, out);
in.close();
in = null;
out.flush();
out.close();
out = null;
} catch (Exception e)
{
Log.e("tag", e.getMessage());
}
if (file.exists()) //Checking for the file is exist or not
{
Uri path = Uri.fromFile(file);
Intent objIntent = new Intent(Intent.ACTION_VIEW);
objIntent.setDataAndType(path, "application/pdf");
objIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
Intent intent1 = Intent.createChooser(objIntent, "Open PDF with..");
try {
startActivity(intent1);
} catch (ActivityNotFoundException e) {
Toast.makeText(getActivity(), "Activity Not Found Exception ", Toast.LENGTH_SHORT).show();
}
} else {
Toast.makeText(getActivity(), "The file not exists! ", Toast.LENGTH_SHORT).show();
}
}
要将文件复制到设备内存中:-
For copy file into device memory:-
private void copyFile(InputStream in, OutputStream out) throws IOException
{
byte[] buffer = new byte[1024];
int read;
while ((read = in.read(buffer)) != -1)
{
out.write(buffer, 0, read);
}
}
使用下面的权限
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
这篇关于尝试使用fileProvider从资产文件夹中打开PDF文件,但它给出FileNotFoundException:没有这样的文件或目录的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!