Opening pdf file Error: This file could not be accessed Check the location or the network and try again. Android 6 Marshmallow

Question

我正在尝试从外部存储中获取文件，然后我必须使用 intents 将该文件发送给 pdf 阅读器。之前下面的代码运行良好，但在安装 Android 6（Marshmallow 更新） 后，我的代码无法运行并收到消息

“无法访问此文件检查位置或网络，然后重试。”

（这是由于新的 android 运行时权限）。我刚刚尝试了所有的解决方案（内容提供商等但没有工作）任何解决方案？

 File file = new File(getFilesDir(), "myfile.pdf");
 Intent intent = new Intent(Intent.ACTION_VIEW);
        intent.setDataAndType(Uri.fromFile(file), "application/pdf");
        intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
        Intent intentChooser = Intent.createChooser(intent, "Choose Pdf Application");
        try {
            startActivity(intentChooser);
        } catch (ActivityNotFoundException e) {
            //com.adobe.reader
            startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("https://play.google.com/store/apps/details?id=com.adobe.reader")));
        }

Answer 1

刚刚为旧的和新的 Android OS 找到了一个可行的解决方案：

第 1 步： 创建一个 class names SampleContentProvider

import android.content.ContentProvider;
import android.content.ContentValues;
import android.database.Cursor;
import android.net.Uri;
import android.os.ParcelFileDescriptor;

import java.io.File;
import java.io.FileNotFoundException;

/**
 * Created by naveed on 7/2/16.
 */
public class SampleContentProvider extends ContentProvider {

    @Override
    public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
        File privateFile = new File(uri.getPath());
        return ParcelFileDescriptor.open(privateFile, ParcelFileDescriptor.MODE_READ_ONLY);
    }

    @Override
    public boolean onCreate() {
        return false;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
        return null;
    }

    @Override
    public String getType(Uri uri) {
        return null;
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        return null;
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        return 0;
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
        return 0;
    }
}

第二步： 在 application body of manifest 中添加提供商：

<provider
        android:name=".SampleContentProvider"
        android:authorities="your_package_name"
        android:exported="true" />

第 3 步： 现在终于通过 Uri

将文件 绝对路径 传递给 intent

  Intent intent = new Intent(Intent.ACTION_VIEW);
        File file = new File(getFilesDir(), "myfile.pdf");
        String absoluteFilePath = file.getAbsolutePath();
        String mimeType = "application/pdf";
        Uri uri = Uri.parse("content://"+"Your_package_name"+"/" + absoluteFilePath);
        intent.setDataAndType(uri, mimeType);
        Intent intentChooser = Intent.createChooser(intent, "Choose Pdf Application");
        startActivity(intentChooser);

希望对您有所帮助。谢谢大家的帮助。

Answer 2

使用FileProvider（这是自Android牛轧糖以来公认的方法——否则你会得到android.os.FileUriExposedException）然后不要忘记授予权限到它需要的所有包：

Uri uri = FileProvider.getUriForFile(
                                context,
                                context.getApplicationContext().getPackageName(), myFile);

                        Intent pdfIntent = new Intent(Intent.ACTION_VIEW);
                        pdfIntent.setDataAndType(apkURI, "application/pdf");
                        pdfIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
                        pdfIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                        grantAllUriPermissions(context, pdfIntent, apkURI);

其中 grantAllUriPermissions():

private void grantAllUriPermissions(Context context, Intent intent, Uri uri) {
        List<ResolveInfo> resInfoList = context.getPackageManager().queryIntentActivities(intent, PackageManager.MATCH_DEFAULT_ONLY);
        for (ResolveInfo resolveInfo : resInfoList) {
            String packageName = resolveInfo.activityInfo.packageName;
            context.grantUriPermission(packageName, uri, Intent.FLAG_GRANT_WRITE_URI_PERMISSION | Intent.FLAG_GRANT_READ_URI_PERMISSION);
        }
}

Answer 3

查看以上答案后，最简单的解决方案如下。

    Uri pdf = FileProvider.getUriForFile(this, this.getApplicationContext().getPackageName() + ".provider", file);

    Intent pdfOpenintent = new Intent(Intent.ACTION_VIEW);
    pdfOpenintent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_ACTIVITY_CLEAR_TOP);
    pdfOpenintent.setDataAndType(pdf, "application/pdf");

    try {
        startActivity(pdfOpenintent);
    } catch (ActivityNotFoundException e) {
        // handle no application here....
    }

关键是要同时设置FLAG_GRANT_READ_URI_PERMISSION和FLAG_ACTIVITY_CLEAR_TOP。

确保在 ApplicationManifest.xml

中声明您的提供商

<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>

她的是 provider_paths 文件

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <external-path name="external_files" path="."/>
</paths>

Answer 4

触发处理已知 MIME 类型文件的意图，代码：

private void openFile(Uri fileUri) {

    String mimeType = mModel.getMimeType(fileUri);

    if (mimeType != null) { //we have determined a mime type and can probably handle the file.
        try {
            /*Implicit intent representing the action we want.  The system will determine is it
            can handle the request.*/
            Intent i = new Intent(Intent.ACTION_VIEW);
            i.setDataAndType(fileUri, mimeType);

            //We ask the Activity to start this intent.
            mView.getActivity().startActivity(i);
        } catch (ActivityNotFoundException e) {
            /*If we have figured out the mime type of the file, but have no application installed
            to handle it, send the user a message.
             */
            Toast.makeText(mView.getActivity(), "The System understands this file type," +
                            "but no applications are installed to handle it.",
                    Toast.LENGTH_LONG).show();
        }
    } else {
        /*if we can't figure out the mime type of the file, let the user know.*/
        Toast.makeText(mView.getActivity(), "System doesn't know how to handle that file type!",
                Toast.LENGTH_LONG).show();
    }
}

Opening pdf file Error: This file could not be accessed Check the location or the network and try again. Android 6 Marshmallow

Opening pdf file Error: This file could not be accessed Check the location or the network and try again. Android 6 Marshmallow

android

android-6.0-marshmallow