android - iText 尝试创建 PDF 文件时出现问题

Question

当我按下按钮时，我正在尝试创建 PDF 文件。我正在使用 iText 库。

我的 Activity :

package com.pdf;

import java.io.FileOutputStream;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;

import com.itextpdf.text.Document;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.pdf.PdfWriter;

public class PDFActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    } 

    public void GenerarPDF(View view)throws Exception{
            Document document=new Document();
            PdfWriter.getInstance(document,new FileOutputStream("generando.pdf"));
            document.open();
            document.add(new Paragraph("Testing testing and testing"));
            document.close();
    }

}

我的 XML:

    <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" android:background="#555">

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="34dp"
        android:ems="10" >

        <requestFocus />
    </EditText>

    <Button
        android:id="@+id/Submit"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/editText1"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="23dp"
        android:onClick="GenerarPDF"
        android:text="Button" />

</RelativeLayout>

我的 list :

    <?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.pdf"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="15" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
    <uses-permission android:name="android.permission.ACCESS_MOCK_LOCATION"/>
    <uses-permission android:name="android.permission.READ_FRAME_BUFFER"/>
    <uses-permission android:name="android.permission.BIND_INPUT_METHOD"/>
    <uses-permission android:name="android.permission.INSTALL_LOCATION_PROVIDER"/>
    <uses-permission android:name="android.permission.INTERNET"/>
    <application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >
    <activity
        android:name=".PDFActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

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

还有日志猫:

05-31 12:08:58.778: E/AndroidRuntime(662): FATAL EXCEPTION: main
05-31 12:08:58.778: E/AndroidRuntime(662): java.lang.IllegalStateException: Could not execute method of the activity
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.view.View$1.onClick(View.java:3044)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.view.View.performClick(View.java:3511)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.view.View$PerformClick.run(View.java:14105)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.os.Handler.handleCallback(Handler.java:605)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.os.Handler.dispatchMessage(Handler.java:92)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.os.Looper.loop(Looper.java:137)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.app.ActivityThread.main(ActivityThread.java:4424)
05-31 12:08:58.778: E/AndroidRuntime(662):  at java.lang.reflect.Method.invokeNative(Native Method)
05-31 12:08:58.778: E/AndroidRuntime(662):  at java.lang.reflect.Method.invoke(Method.java:511)
05-31 12:08:58.778: E/AndroidRuntime(662):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
05-31 12:08:58.778: E/AndroidRuntime(662):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
05-31 12:08:58.778: E/AndroidRuntime(662):  at dalvik.system.NativeStart.main(Native Method)
05-31 12:08:58.778: E/AndroidRuntime(662): Caused by: java.lang.reflect.InvocationTargetException
05-31 12:08:58.778: E/AndroidRuntime(662):  at java.lang.reflect.Method.invokeNative(Native Method)
05-31 12:08:58.778: E/AndroidRuntime(662):  at java.lang.reflect.Method.invoke(Method.java:511)
05-31 12:08:58.778: E/AndroidRuntime(662):  at android.view.View$1.onClick(View.java:3039)
05-31 12:08:58.778: E/AndroidRuntime(662):  ... 11 more
05-31 12:08:58.778: E/AndroidRuntime(662): Caused by: java.lang.NoClassDefFoundError: com.itextpdf.text.Document
05-31 12:08:58.778: E/AndroidRuntime(662):  at com.pdf.PDFActivity.GenerarPDF(PDFActivity.java:22)
05-31 12:08:58.778: E/AndroidRuntime(662):  ... 14 more

添加了 logcat 错误:

05-31 15:26:00.411: E/dalvikvm(792): Could not find class 'com.itextpdf.text.Document', referenced from method com.pdf.PDFActivity.GenerarPDF

我认为这就是真正的问题，但不知道解决方案。

Answer 1

您到底想在哪里创建 pdf 文件？我使用了itextpdf-5.2.1.jar并且能够在sd卡中成功创建pdf。我在您的程序中添加了以下几行代码:

public void GenerarPDF(View view)throws Exception{
        Document document=new Document();
        File root = new File(Environment.getExternalStorageDirectory(), "Notes");
        if (!root.exists()) {
            root.mkdirs();
        }
        File gpxfile = new File(root, "generando.pdf");
        PdfWriter.getInstance(document,new FileOutputStream(gpxfile));
        document.open();
        document.add(new Paragraph("Testing testing and testing"));
        document.close();
} 

希望这个答案有帮助。

编辑: 您在评论中提到的错误 (06-01 23:32:37.178: E/AndroidRuntime(535): Caused by: java.io.FileNotFoundException:/generando.pdf: open failed: EROFS (Read-only file system) )正是我运行您提供的代码时得到的结果。原因是您没有指定可以创建/存储新文件的位置。使用粘贴到此处的 GenerarPDF(查看 View )，程序将创建新的 pdf。

导致此错误的另一个原因可能是您的设备中没有 SD 卡。