Android加载pdf

依赖

implementation 'com.squareup.okhttp3:okhttp:4.9.1'
implementation 'com.github.barteksc:android-pdf-viewer:3.2.0-beta.1'

在project.build中添加该源

maven { url "https://repository.liferay.com/nexus/content/repositories/public/" }

XML

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><com.github.barteksc.pdfviewer.PDFViewandroid:id="@+id/pdfView"android:layout_width="match_parent"android:layout_height="match_parent"/>
</LinearLayout>

Activity

import android.os.Bundle;
import android.os.Environment;
import androidx.appcompat.app.AppCompatActivity;
import com.github.barteksc.pdfviewer.PDFView;
import okhttp3.Call;
import okhttp3.Callback;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;public class MainActivity extends AppCompatActivity {private PDFView pdfView;private static final String PDF_URL = "https://www.example.com/sample.pdf"; // 替换为你的 PDF URL@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);pdfView = findViewById(R.id.pdfView);downloadAndDisplayPdf(PDF_URL);}private void downloadAndDisplayPdf(String url) {OkHttpClient client = new OkHttpClient();Request request = new Request.Builder().url(url).build();client.newCall(request).enqueue(new Callback() {@Overridepublic void onFailure(Call call, IOException e) {e.printStackTrace();}@Overridepublic void onResponse(Call call, Response response) throws IOException {if (response.isSuccessful()) {File pdfFile = new File(getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS), "downloaded.pdf");try (InputStream inputStream = response.body().byteStream();FileOutputStream outputStream = new FileOutputStream(pdfFile)) {byte[] buffer = new byte[2048];int length;while ((length = inputStream.read(buffer)) != -1) {outputStream.write(buffer, 0, length);}// 在主线程中加载 PDFrunOnUiThread(() -> pdfView.fromFile(pdfFile).load());}}}});}
}

PDF不支持在线预览，因此要先下载后加载•	下载 PDF 文件：使用 OkHttp 请求 PDF 的在线地址，并将其保存到设备的下载目录中。
•	加载 PDF 文件：下载完成后，通过 pdfView.fromFile(pdfFile).load() 在 PDFView 中显示 PDF 文件。