【学习笔记】Android-pdfview

开发环境:Win10,1909; Android Studio 3.5.3 , 华为Mate10 Pro，Android10.0

1.AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.pdfviewershow">
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme"
        android:requestLegacyExternalStorage="true">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

android:requestLegacyExternalStorage="true"，这句非常重要，参考https://www.cnblogs.com/endv/p/12164605.html
如果不加上，读取文件一直是Permission denied

2.添加PDFView

implementation 'com.github.barteksc:android-pdf-viewer:3.2.0-beta.1'

添加完，点sync

3.activity_main.xml，这里什么功能都没添加，很简单的

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout android:layout_height="match_parent"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent">

    <com.github.barteksc.pdfviewer.PDFView
        android:id="@+id/pdfview"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
    </com.github.barteksc.pdfviewer.PDFView>
</LinearLayout>

4. MainActivity.java，这里也很简单，网上都能找的到

package com.example.pdfviewershow;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.content.ContextCompat;

import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Build;
import android.os.Bundle;
import android.os.Environment;
import android.widget.Toast;

import com.github.barteksc.pdfviewer.PDFView;
import com.github.barteksc.pdfviewer.listener.OnLoadCompleteListener;

import java.io.File;

public class MainActivity extends AppCompatActivity {
    private static final int REQUEST_EXTERNAL_STORAGE = 1;
    private PDFView pdfView;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        getSDPath();
        getPermission();

        pdfView = findViewById(R.id.pdfview);
//        /storage/sdcard0/Documents/CMCC.pdf
        File fPdfPath = new File("/sdcard/Download/CMCC.pdf");
        if(!fPdfPath.exists())
        {
            System.out.println("FILE *****************************");
        }
        pdfView.fromFile(fPdfPath)
                .enableSwipe(true)
                .swipeHorizontal(true)
                .enableDoubletap(false)
                .defaultPage(0)
                .onLoad(new OnLoadCompleteListener() {
                    @Override
                    public void loadComplete(int nbPages) {
                       Toast.makeText(getBaseContext(),"loadComplete",Toast.LENGTH_LONG);
                    }
                })
                .enableAnnotationRendering(false)
                .password(null)
                .scrollHandle(null)
                .enableAntialiasing(true)
                .spacing(0)
                .load();
    }

    public void getSDPath(){
        File sdDir = null;
        File sdDir1 = null;
        File sdDir2 = null;
        boolean sdCardExist = Environment.getExternalStorageState()
                .equals(android.os.Environment.MEDIA_MOUNTED); //判断sd卡是否存在
        if (sdCardExist)
        {
            sdDir = Environment.getExternalStorageDirectory();//获取跟目录
            sdDir1 = Environment.getDataDirectory();
            sdDir2 =Environment.getRootDirectory();
        }
        System.out.println("getExternalStorageDirectory(): "+sdDir.toString());
        System.out.println("getDataDirectory(): "+sdDir1.toString());
        System.out.println("getRootDirectory(): "+sdDir2.toString());
    }

    private void getPermission() {
            //验证是否许可权限
    //        requestPermissions(new String[]{ Manifest.permission.READ_EXTERNAL_STORAGE},0x123);
            requestPermissions(new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},0x456);
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        if (requestCode == 0x123)
        {
            if (grantResults != null && grantResults[0] == PackageManager.PERMISSION_GRANTED )
            {
                Toast.makeText(this,"已授权READ_EXTERNAL_STORAGE",Toast.LENGTH_LONG);
            }
        }
        if (requestCode == 0x456)
        {
            if (grantResults != null && grantResults[0] == PackageManager.PERMISSION_GRANTED)
            {
                Toast.makeText(this,"已授权WRITE_EXTERNAL_STORAGE",Toast.LENGTH_LONG);
            }
        }
    }
}

6，效果如下