Android生成PDF文件、webview加载本地PDF或者网络PDF

生成pdf

Andrid端生成PDF局限性太差，尚未有优雅的解决方案。但网上众说纷纭，实践者少之又少，高质量的博文也是凤毛麟角，大家都是博文搬用工，也没有谁做过详细的探索。笔者就自己的一点经验做点分享。

使用iText

iText不支持中文，要支持中文需要引入额外包需要添加一个额外的jar包：itext-asian.jar。亲测较好的方案直接引入再次封装过的jar包：http://download.csdn.net/detail/xuwenneng/9669969

在Android studio中不需要在引入包，把它加入即可。

实例代码（源于网络，本人亲测）：

package com.dyb.createpdf;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;

import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Font;
import com.itextpdf.text.Image;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.PdfWriter;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class MainActivity extends AppCompatActivity {
private TextView mTextview;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTextview = (TextView) findViewById(R.id.create_pdf);

mTextview.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Document doc = new Document();
FileOutputStream fos;
try {
fos = new FileOutputStream(new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/createLocal.pdf"));
PdfWriter.getInstance(doc, fos);
doc.open();
doc.setPageCount(1);
doc.add(new Paragraph("testpdf~~成功哩", setChineseFont()));

myImg.setAlignment(Image.MIDDLE);
doc.add(myImg);
//一定要记得关闭document对象
doc.close();
fos.flush();
fos.close();
Toast.makeText(MainActivity.this, "Environment.getExternalStorageDirectory()/createLocal.pdf ", Toast.LENGTH_LONG).show();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (DocumentException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}

// 产生PDF字体
public static Font setChineseFont() {
BaseFont bf = null;
Font fontChinese = null;
try {
bf = BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.NOT_EMBEDDED);
fontChinese = new Font(bf, 12, Font.NORMAL);
} catch (DocumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return fontChinese;
}
}

注意：

1.此种方案加入图片生成PDF并未成功。

使用官方API中鲜为人知的api

此种方式简单粗暴，直接把xml布局重新绘制在画布上，保存。显然处理不当你的光标也被保存了。（通俗点就是截屏）

package hu.autsoft.androidapidemos;

import android.Manifest;
import android.content.pm.PackageManager;
import android.graphics.Point;
import android.graphics.Rect;
import android.graphics.pdf.PdfDocument;
import android.os.Environment;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Toast;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import butterknife.BindView;
import butterknife.ButterKnife;
import butterknife.OnClick;

public class PDFCreateActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_pdfcreate);

ButterKnife.bind(this);

requestNeededPermission();
}

public void requestNeededPermission() {
if (ContextCompat.checkSelfPermission(this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
if (ActivityCompat.shouldShowRequestPermissionRationale(this,
Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
Toast.makeText(PDFCreateActivity.this,
"I need it for pdf creating", Toast.LENGTH_SHORT).show();
}

ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
101);
} else {
Toast.makeText(PDFCreateActivity.this,
"WRITE_EXTERNAL_STORAGE perm granted", Toast.LENGTH_SHORT).show();
}
}

@Override
public void onRequestPermissionsResult(int requestCode,
String permissions[], int[] grantResults) {
switch (requestCode) {
case 101: {
// If request is cancelled, the result arrays are empty.
if (grantResults.length > 0
&& grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(PDFCreateActivity.this,
"WRITE_EXTERNAL_STORAGE perm granted", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(PDFCreateActivity.this,
"WRITE_EXTERNAL_STORAGE perm NOT granted", Toast.LENGTH_SHORT).show();
}
return;
}
}
}

@OnClick(R.id.btnCreatePdf)
public void createPdfClicked(View v) {
new Thread() {
public void run() {
// Get the directory for the app's private pictures directory.
final File file = new File(
Environment.getExternalStorageDirectory(), "demo.pdf");
if (file.exists()) {
file.delete();
}

FileOutputStream out = null;
try {
out = new FileOutputStream(file);
PdfDocument document = new PdfDocument();
Point windowSize = new Point();
getWindowManager().getDefaultDisplay().getSize(windowSize);
PdfDocument.PageInfo pageInfo =
new PdfDocument.PageInfo.Builder(
windowSize.x, windowSize.y, 1).create();
PdfDocument.Page page = document.startPage(pageInfo);
View content = getWindow().getDecorView();
content.draw(page.getCanvas());
document.finishPage(page);
document.writeTo(out);
document.close();
out.flush();

runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(PDFCreateActivity.this, "File created: " + file.getAbsolutePath(), Toast.LENGTH_LONG).show();
}
});
} catch (Exception e) {
Log.d("TAG_PDF", "File was not created: " + e.getMessage());
} finally {
try {
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}.start();
}
}

webview读取pdf

webview读取PDF也是比较恶心的，因为原生webview是不支持PDF的。此处就要借助一些磕磕巴巴第三方，同样存在很多不完善之处。本人亲测，使用了较为好的三方。

本地PDF

com.github.barteksc.pdfviewer

package com.dyb.loadpdf;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;

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

/**
* android 加载本地pdf文件
* com.github.barteksc.pdfviewer
*/
public class MainActivity extends AppCompatActivity implements OnLoadCompleteListener, OnPageChangeListener {
private TextView mTexview, mTexviewNet;
private PDFView pdfView;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTexview = (TextView) findViewById(R.id.pdf);
mTexviewNet = (TextView) findViewById(R.id.textView_new_pdf);
pdfView = (PDFView) findViewById(R.id.pdfView);
mTexview.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
pdfView.fromAsset("sample.pdf")
.defaultPage(0)
.onPageChange(MainActivity.this)
.enableAnnotationRendering(true)
.onLoad(MainActivity.this)
.enableSwipe(true)
.swipeHorizontal(false)
.load();
}
});
}

@Override
public void loadComplete(int nbPages) {

}

@Override
public void onPageChanged(int page, int pageCount) {

}
}

在线PDF

com.lidong.pdf:android_pdf:1.0.1

package com.dyb.loadpdf;

import android.graphics.Canvas;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;

import com.lidong.pdf.PDFView;
import com.lidong.pdf.listener.OnDrawListener;
import com.lidong.pdf.listener.OnLoadCompleteListener;
import com.lidong.pdf.listener.OnPageChangeListener;

public class MainActivityNet extends AppCompatActivity implements OnPageChangeListener, OnLoadCompleteListener, OnDrawListener {
private PDFView pdfViewNet;//网络
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_net);
pdfViewNet = (PDFView) findViewById(R.id.pdfView_net_new);
displayFromFile("http://file.chmsp.com.cn/colligate/file/00100000224821.pdf", "00100000224821.pdf");
}

private void displayFromFile(String fileUrl, String fileName) {
pdfViewNet.fileFromLocalStorage(this, this, this, fileUrl, fileName);   //设置pdf文件地址
}

@Override
public void onLayerDrawn(Canvas canvas, float pageWidth, float pageHeight, int displayedPage) {

}

@Override
public void loadComplete(int nbPages) {

}

@Override
public void onPageChanged(int page, int pageCount) {

}
}