Android内嵌MuPDF打开PDF文件
一、基本实现
1，导入so库；
2，声明库文件中方法
public class MuPDFCore {
/* load our native library */
static {
System.loadLibrary("mupdf");
}
/* Readable members */
private int pageNum = -1;;
private int numPages = -1;
public float pageWidth;
public float pageHeight;
/* The native functions */
private static native int openFile(String filename);
private static native int countPagesInternal();
private static native void gotoPageInternal(int localActionPageNum);
private static native float getPageWidth();
private static native float getPageHeight();
public static native void drawPage(Bitmap bitmap, int pageW, int pageH,
int patchX, int patchY, int patchW, int patchH);
public static native RectF[] searchPage(String text);
public static native int getPageLink(int page, float x, float y);
public static native boolean hasOutlineInternal();
public static native boolean needsPasswordInternal();
public static native boolean authenticatePasswordInternal(String password);
public static native void destroying();
public MuPDFCore(String filename) throws Exception {
if (openFile(filename) <= 0) {
throw new Exception("Failed to open " + filename);
}
}
public int countPages() {
if (numPages < 0)
numPages = countPagesSynchronized();
return numPages;
}
private synchronized int countPagesSynchronized() {
return countPagesInternal();
}
/* Shim function */
public void gotoPage(int page) {
if (page > numPages - 1)
page = numPages - 1;
else if (page < 0)
page = 0;
if (this.pageNum == page)
return;
gotoPageInternal(page);
this.pageNum = page;
this.pageWidth = getPageWidth();
this.pageHeight = getPageHeight();
}
public synchronized PointF getPageSize(int page) {
gotoPage(page);
return new PointF(pageWidth, pageHeight);
}
public synchronized void onDestroy() {
destroying();
}
public synchronized void drawPage(int page, Bitmap bitmap, int pageW,int pageH, int patchX, int patchY, int patchW, int patchH) {
gotoPage(page);
drawPage(bitmap, pageW, pageH, patchX, patchY, patchW, patchH);
}
public synchronized int hitLinkPage(int page, float x, float y) {
return getPageLink(page, x, y);
}
public synchronized RectF[] searchPage(int page, String text) {
gotoPage(page);
return searchPage(text);
}
public synchronized boolean hasOutline() {
return hasOutlineInternal();
}
public synchronized boolean needsPassword() {
return needsPasswordInternal();
}
public synchronized boolean authenticatePassword(String password) {
return authenticatePasswordInternal(password);
}
}
3，使用
public class MuPDFActivity extends BaseActivity {
private MuPDFCore core;
private String mFileName;
private ListView mDocListView;
private View mButtonsView;
private boolean mButtonsVisible;
private EditText mPasswordView;
private TextView mFilenameView;
private SeekBar mPageSlider;
private TextView mPageNumberView;
private ViewSwitcher mTopBarSwitcher;
private ProgressBar loadingPB;
private MyMuPDFPageAdapter pdfPageAdapter;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (core == null) {
File sdcardDir = Environment.getExternalStorageDirectory();
// 得到一个路径，内容是sdcard的文件夹路径和名字
String path = sdcardDir.getPath() + "/MyMobileDownlod/test.pdf";
int lastSlashPos = path.lastIndexOf('/');
mFileName = new String(lastSlashPos == -1 ? path
: path.substring(lastSlashPos + 1));
System.out.println("Trying to open " + path);
try {
core = new MuPDFCore(path);
} catch (Exception e) {
}
if (core != null && core.needsPassword()) {
return;
}
}
if (core == null) {
AlertDialog alert = new AlertDialog.Builder(this).create();
alert.setTitle(R.string.open_failed);
alert.setButton(AlertDialog.BUTTON_POSITIVE, "Dismiss",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
alert.show();
return;
}
createUI(savedInstanceState);
}
public void createUI(Bundle savedInstanceState) {
mDocListView = new ListView(this);
pdfPageAdapter = new MyMuPDFPageAdapter(this, core);
mDocListView.setAdapter(pdfPageAdapter);
mButtonsView = getLayoutInflater().inflate(R.layout.buttons, null);
mFilenameView = (TextView) mButtonsView.findViewById(R.id.docNameText);
loadingPB = (ProgressBar) mButtonsView.findViewById(R.id.loadingPB);
mTopBarSwitcher = (ViewSwitcher) mButtonsView
.findViewById(R.id.switcher);
mTopBarSwitcher.setDisplayedChild(0);
mTopBarSwitcher.setVisibility(View.VISIBLE);
loadingPB.setVisibility(View.INVISIBLE);
mFilenameView.setText("Name:" + mFileName
+ String.format(" SumPage:%d", core.countPages()));
RelativeLayout layout = new RelativeLayout(this);
layout.addView(mDocListView);
layout.addView(mButtonsView);
layout.setBackgroundResource(R.drawable.tiled_background);
setContentView(layout);
}
public void onDestroy() {
if (core != null)
core.onDestroy();
core = null;
super.onDestroy();
}
@Override
protected void dispatchMsgOP(Message msg) {
super.dispatchMsgOP(msg);
if (1 == msg.what) {
Toast.makeText(MuPDFActivity.this, "loading", Toast.LENGTH_SHORT)
.show();
loadingPB.setVisibility(View.VISIBLE);
} else {
loadingPB.setVisibility(View.INVISIBLE);
}
}
}
实际使用说明：
当前PDF阅读器的实质是一个ListView，从而可以实现当前页面的重新布局，以达到实际需求。如：title栏变更效果，增加“分享”等后续操作。
二、so库的使用
1，导入so库源文件
so库分包有armeabi，arm64-v8a，armeabi-v7a等，是针对不同的ARM设备的包。armeabi，armeabi-v7a是32位ARM设备，arm64-v8a是64位ARM设备。arm64-v8a是向下兼容的，每个包有自己的优化和处理，最理想的条件是每个设备类型都有对应的so库文件。
注意事项是arm64-v8a中一定要有全部的armeabi的源文件，否则在调用到armeabi中独有的就会出错。当存在arm64-v8a中没有armeabi的so库文件时，只能删除整个包，保证程序能够正常运行。
2，关联库文件
static {
System.loadLibrary("mupdf");//加载库文件
}三、使用细节注意
1，包名一致【JNI调用规则】
Java_ + 包名（com.lucyfyr） + 类名(HelloWorld) + 接口名(printJNI)：必须要按此JNI规范来操作；
so库文件中方法在使用时，必须保证使用环境的包名与so库文件编译生成的包名一致。
2，so库的注意事项
注意事项：arm64-v8a中一定要有全部的armeabi的源文件，否则在调用到armeabi中独有文件方法时就会出错。当存在arm64-v8a中没有armeabi的so库文件时，只能删除整个包，保证程序能够正常运行。或者重新编译生成so库文件。
这里是源码
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