pdf文件查看在android中遇到问题

Question

嗨，在 pdf 代码中，我有一个按钮查看 pdf。当单击 pdf 时，我以字符串 url 的形式访问文件，然后想要打开 pdf 文件。但是当我尝试单击下面的按钮时问题。来自外部目录

谁能帮我解决这个问题。

pdf：

holder.pdf.setOnClickListener(new View.OnClickListener() {

        @Override public void onClick(View v) {
            File file = new File(Environment.getExternalStorageDirectory(),
                    opportunity.getPdf_link());
            Uri path = Uri.fromFile(file);
            Uri pdf = FileProvider.getUriForFile(mContext, mContext.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 {
                mContext.startActivity(pdfOpenintent);
            } catch (ActivityNotFoundException e) {
                // handle no application here....
            }
        }

    });

在清单中：

 <provider
            android:name="androidx.core.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>

 android.os.FileUriExposedException: file:///storage/emulated/0/https%3A/www.w3.org/WAI/ER/tests/xhtml/testfiles/resources/pdf/dummy.pdf exposed beyond app through Intent.getData()
        at android.os.StrictMode.onFileUriExposed(StrictMode.java:1978)
        at android.net.Uri.checkFileUriExposed(Uri.java:2371)
        at android.content.Intent.prepareToLeaveProcess(Intent.java:10247)
        at android.content.Intent.prepareToLeaveProcess(Intent.java:10201)
        at android.app.Instrumentation.execStartActivity(Instrumentation.java:1667)
        at android.app.Activity.startActivityForResult(Activity.java:4586)
        at androidx.fragment.app.FragmentActivity.startActivityForResult(FragmentActivity.java:767)
        at android.app.Activity.startActivityForResult(Activity.java:4544)

Answer 1

FileProvider 需要从 targetSdkVersion >= 24 访问文件夹。在 @res/xml 文件夹 provider_paths.xml 中创建一个 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="."/>
</paths>

并将其添加到清单

  <provider
        android:name="androidx.core.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>

改变

 Uri path = Uri.fromFile(file);

到

Uri uri = FileProvider.getUriForFile(MainActivity.this, BuildConfig.APPLICATION_ID + ".provider",file);

改变

Intent pdfOpenintent = new Intent(Intent.ACTION_VIEW);
File file = new File(Environment.getExternalStorageDirectory(),
                        opportunity.getPdf_link());
               // Uri path = Uri.fromFile(file);
                Uri pdf = FileProvider.getUriForFile(mContext, mContext.getPackageName() + ".provider", file);


                pdfOpenintent.setDataAndType(pdf, "application/pdf");
                pdfOpenintent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

mContext.startActivity(intent);

希望这会有所帮助.....