Qt在Android平台上实现html转PDF的功能

Qt for Android

Qt for Android enables you to run Qt 5 applications Android devices. All Qt modules (essential and add-on) are supported except Qt WebEngine, Qt Serial Port, and the platform-specific ones (Qt Mac Extras, Qt Windows Extras, and Qt X11 Extras).

 

在Windows或者Linux平台上可以用QtWebEngine模块实现网页预览和打印成PDF文档,用起来很方便,生成的文档质量也比较好,但在Android平台上QtWebEngine模块不能用,想要显示网页可以用QtWebView模块,不支持打印成PDF。尝试用QTextDocument和QPrinter将html转为PDF,发现QTextDocument不支持CSS样式,生成的PDF文档排版是错的。

 

查看QtWebView在Android平台上的实现,可以发现其用的就是Android的WebView控件实现的网页显示。尝试在Android平台上实现html生成PDF,找到了这篇文章https://www.jianshu.com/p/d82bd61b11a4,验证后可行。需要依赖第三方库DexMaker,可以用谷歌实现的 implementation 'com.google.dexmaker:dexmaker:1.2',库文件名为dexmaker-1.2.jar。

 

修改QT源码,在Android平台上实现html转PDF的功能

  • 修改$QtSrc/qtwebview/src/jar/src/org/qtproject/qt5/android/view/QtAndroidWebViewController.java文件
    /****************************************************************************
    **
    ** Copyright (C) 2015 The Qt Company Ltd.
    ** Contact: http://www.qt.io/licensing/
    **
    ** This file is part of the QtWebView module of the Qt Toolkit.
    **
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    ** accordance with the commercial license agreement provided with the
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    ** and conditions see http://www.qt.io/terms-conditions. For further
    ** information use the contact form at http://www.qt.io/contact-us.
    **
    ** GNU Lesser General Public License Usage
    ** Alternatively, this file may be used under the terms of the GNU Lesser
    ** General Public License version 3 as published by the Free Software
    ** Foundation and appearing in the file LICENSE.LGPLv3 included in the
    ** packaging of this file. Please review the following information to
    ** ensure the GNU Lesser General Public License version 3 requirements
    ** will be met: https://www.gnu.org/licenses/lgpl.html.
    **
    ** GNU General Public License Usage
    ** Alternatively, this file may be used under the terms of the GNU
    ** General Public License version 2.0 or later as published by the Free
    ** Software Foundation and appearing in the file LICENSE.GPL included in
    ** the packaging of this file. Please review the following information to
    ** ensure the GNU General Public License version 2.0 requirements will be
    ** met: http://www.gnu.org/licenses/gpl-2.0.html.
    **
    ** $QT_END_LICENSE$
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    ****************************************************************************/
    
    package org.qtproject.qt5.android.view;
    
    import android.content.pm.PackageManager;
    import android.view.View;
    import android.webkit.GeolocationPermissions;
    import android.webkit.URLUtil;
    import android.webkit.ValueCallback;
    import android.annotation.SuppressLint;
    import android.content.Context;
    import android.os.Bundle;
    import android.os.CancellationSignal;
    import android.os.ParcelFileDescriptor;
    import android.print.PageRange;
    import android.print.PrintAttributes;
    import android.print.PrintDocumentAdapter;
    import android.webkit.WebView;
    import android.webkit.WebViewClient;
    import android.webkit.WebChromeClient;
    
    import java.lang.Runnable;
    
    import android.app.Activity;
    import android.content.Intent;
    import android.net.Uri;
    
    import java.lang.String;
    
    import android.webkit.WebSettings;
    import android.webkit.WebSettings.PluginState;
    import android.graphics.Bitmap;
    
    import java.util.concurrent.Semaphore;
    import java.io.File;
    import java.io.IOException;
    import java.lang.reflect.InvocationHandler;
    import java.lang.reflect.Method;
    
    import android.os.Build;
    
    import java.util.concurrent.TimeUnit;
    
    import com.google.dexmaker.stock.ProxyBuilder;
    
    public class QtAndroidWebViewController
    {
        private final Activity m_activity;
        private final long m_id;
        private boolean busy;
        private boolean m_hasLocationPermission;
        private WebView m_webView = null;
        private static final String TAG = "QtAndroidWebViewController";
        private final int INIT_STATE = 0;
        private final int STARTED_STATE = 1;
        private final int LOADING_STATE = 2;
        private final int FINISHED_STATE = 3;
    
        private volatile int m_loadingState = INIT_STATE;
        private volatile int m_progress = 0;
        private volatile int m_frameCount = 0;
    
        // API 11 methods
        private Method m_webViewOnResume = null;
        private Method m_webViewOnPause = null;
        private Method m_webSettingsSetDisplayZoomControls = null;
    
        // API 19 methods
        private Method m_webViewEvaluateJavascript = null;
    
        // Native callbacks
        private native void c_onPageFinished(long id, String url);
        private native void c_onPageStarted(long id, String url, Bitmap icon);
        private native void c_onProgressChanged(long id, int newProgress);
        private native void c_onReceivedIcon(long id, Bitmap icon);
        private native void c_onReceivedTitle(long id, String title);
        private native void c_onRunJavaScriptResult(long id, long callbackId, String result);
        private native void c_onReceivedError(long id, int errorCode, String description, String url);
        private native void c_onpdfPrintingFinished(long id, boolean succeed);
    
        // We need to block the UI thread in some cases, if it takes to long we should timeout before
        // ANR kicks in... Usually the hard limit is set to 10s and if exceed that then we're in trouble.
        // In general we should not let input events be delayed for more then 500ms (If we're spending more
        // then 200ms somethings off...).
        private final long BLOCKING_TIMEOUT = 250;
    
        private void resetLoadingState(final int state)
        {
            m_progress = 0;
            m_frameCount = 0;
            m_loadingState = state;
        }
    
        private class Html2Pdf {
            private File file;
            private File dexCacheFile;
            private PrintDocumentAdapter printAdapter;
            private PageRange[] ranges;
            private ParcelFileDescriptor descriptor;
        
            private void printToPdf(WebView webView, String fileName) {
                if (webView != null) {
                    file = new File(fileName);
                    dexCacheFile = webView.getContext().getDir("dex", 0);
                    if (!dexCacheFile.exists()) {
                        dexCacheFile.mkdir();
                    }
                    try {
                        if (file.exists()) {
                            file.delete();
                        }
                        file.createNewFile();
                        descriptor = ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_WRITE);
                        PrintAttributes attributes = new PrintAttributes.Builder()
                                .setMediaSize(PrintAttributes.MediaSize.ISO_A4)
                                .setResolution(new PrintAttributes.Resolution("id", Context.PRINT_SERVICE, 300, 300))
                                .setColorMode(PrintAttributes.COLOR_MODE_COLOR)
                                .setMinMargins(PrintAttributes.Margins.NO_MARGINS)
                                .build();
                        ranges = new PageRange[]{PageRange.ALL_PAGES};
        
                        printAdapter = webView.createPrintDocumentAdapter();
                        printAdapter.onStart();
                        printAdapter.onLayout(attributes, attributes, new CancellationSignal(), getLayoutResultCallback(new InvocationHandler() {
                            @Override
                            public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                                if (method.getName().equals("onLayoutFinished")) {
                                    onLayoutSuccess();
                                } else {
                                    descriptor.close();
                                    c_onpdfPrintingFinished(m_id, false);
                                    busy = false;
                                }
                                return null;
                            }
                        }, dexCacheFile.getAbsoluteFile()), new Bundle());
                    } catch (IOException e) {
                        if (descriptor != null) {
                            try {
                                descriptor.close();
                            } catch (IOException ex) {
                                ex.printStackTrace();
                            }
                        }
                        c_onpdfPrintingFinished(m_id, false);
                        e.printStackTrace();
                        busy = false;
                    }
                }
            }
        
            private void onLayoutSuccess() throws IOException {
                PrintDocumentAdapter.WriteResultCallback callback = getWriteResultCallback(new InvocationHandler() {
                    @Override
                    public Object invoke(Object o, Method method, Object[] objects) throws Throwable {
                        if (method.getName().equals("onWriteFinished")) {
                            c_onpdfPrintingFinished(m_id, true);
                        } else {
                            c_onpdfPrintingFinished(m_id, false);
                        }
                        busy = false;
                        if (descriptor != null) {
                            try {
                                descriptor.close();
                            } catch (IOException ex) {
                                ex.printStackTrace();
                            }
                        }
                        return null;
                    }
                }, dexCacheFile.getAbsoluteFile());
                printAdapter.onWrite(ranges, descriptor, new CancellationSignal(), callback);
            }
        
            @SuppressLint("NewApi")
            private  PrintDocumentAdapter.LayoutResultCallback getLayoutResultCallback(InvocationHandler invocationHandler, File dexCacheDir) throws IOException {
                return ProxyBuilder.forClass(PrintDocumentAdapter.LayoutResultCallback.class)
                        .dexCache(dexCacheDir)
                        .handler(invocationHandler)
                        .build();
            }
        
            @SuppressLint("NewApi")
            private  PrintDocumentAdapter.WriteResultCallback getWriteResultCallback(InvocationHandler invocationHandler, File dexCacheDir) throws IOException {
                return ProxyBuilder.forClass(PrintDocumentAdapter.WriteResultCallback.class)
                        .dexCache(dexCacheDir)
                        .handler(invocationHandler)
                        .build();
            }    
        }
    
        private class QtAndroidWebViewClient extends WebViewClient
        {
            QtAndroidWebViewClient() { super(); }
    
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url)
            {
                // handle http: and http:, etc., as usual
                if (URLUtil.isValidUrl(url))
                    return false;
    
                // try to handle geo:, tel:, mailto: and other schemes
                try {
                    Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
                    view.getContext().startActivity(intent);
                    return true;
                } catch (Exception e) {
                    e.printStackTrace();
                }
    
                return false;
            }
    
            @Override
            public void onLoadResource(WebView view, String url)
            {
                super.onLoadResource(view, url);
            }
    
            @Override
            public void onPageFinished(WebView view, String url)
            {
                super.onPageFinished(view, url);
                m_loadingState = FINISHED_STATE;
                if (m_progress != 100) // onProgressChanged() will notify Qt if we didn't finish here.
                    return;
    
                 m_frameCount = 0;
                 c_onPageFinished(m_id, url);
            }
    
            @Override
            public void onPageStarted(WebView view, String url, Bitmap favicon)
            {
                super.onPageStarted(view, url, favicon);
                if (++m_frameCount == 1) { // Only call onPageStarted for the first frame.
                    m_loadingState = LOADING_STATE;
                    c_onPageStarted(m_id, url, favicon);
                }
            }
    
            @Override
            public void onReceivedError(WebView view,
                                        int errorCode,
                                        String description,
                                        String url)
            {
                super.onReceivedError(view, errorCode, description, url);
                resetLoadingState(INIT_STATE);
                c_onReceivedError(m_id, errorCode, description, url);
            }
        }
    
        private class QtAndroidWebChromeClient extends WebChromeClient
        {
            QtAndroidWebChromeClient() { super(); }
            @Override
            public void onProgressChanged(WebView view, int newProgress)
            {
                super.onProgressChanged(view, newProgress);
                m_progress = newProgress;
                c_onProgressChanged(m_id, newProgress);
                if (m_loadingState == FINISHED_STATE && m_progress == 100) { // Did we finish?
                    m_frameCount = 0;
                    c_onPageFinished(m_id, view.getUrl());
                }
            }
    
            @Override
            public void onReceivedIcon(WebView view, Bitmap icon)
            {
                super.onReceivedIcon(view, icon);
                c_onReceivedIcon(m_id, icon);
            }
    
            @Override
            public void onReceivedTitle(WebView view, String title)
            {
                super.onReceivedTitle(view, title);
                c_onReceivedTitle(m_id, title);
            }
    
            @Override
            public void onGeolocationPermissionsShowPrompt(String origin, GeolocationPermissions.Callback callback)
            {
                callback.invoke(origin, m_hasLocationPermission, false);
            }
        }
    
        public QtAndroidWebViewController(final Activity activity, final long id)
        {
            m_activity = activity;
            m_id = id;
            final Semaphore sem = new Semaphore(0);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    m_webView = new WebView(m_activity);
                    m_hasLocationPermission = hasLocationPermission(m_webView);
                    WebSettings webSettings = m_webView.getSettings();
    
                    if (Build.VERSION.SDK_INT > 10) {
                        try {
                            m_webViewOnResume = m_webView.getClass().getMethod("onResume");
                            m_webViewOnPause = m_webView.getClass().getMethod("onPause");
                            m_webSettingsSetDisplayZoomControls = webSettings.getClass().getMethod("setDisplayZoomControls", boolean.class);
                            if (Build.VERSION.SDK_INT > 18) {
                                m_webViewEvaluateJavascript = m_webView.getClass().getMethod("evaluateJavascript",
                                                                                             String.class,
                                                                                             ValueCallback.class);
                            }
                        } catch (Exception e) { /* Do nothing */ e.printStackTrace(); }
                    }
    
                    //allowing access to location without actual ACCESS_FINE_LOCATION may throw security exception
                    webSettings.setGeolocationEnabled(m_hasLocationPermission);
    
                    webSettings.setJavaScriptEnabled(true);
                    if (m_webSettingsSetDisplayZoomControls != null) {
                        try { m_webSettingsSetDisplayZoomControls.invoke(webSettings, false); } catch (Exception e) { e.printStackTrace(); }
                    }
                    webSettings.setBuiltInZoomControls(true);
                    webSettings.setPluginState(PluginState.ON);
                    m_webView.setWebViewClient((WebViewClient)new QtAndroidWebViewClient());
                    m_webView.setWebChromeClient((WebChromeClient)new QtAndroidWebChromeClient());
                    sem.release();
                }
            });
    
            try {
                sem.acquire();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    
        public void loadUrl(final String url)
        {
            if (url == null) {
                return;
            }
    
            resetLoadingState(STARTED_STATE);
            c_onPageStarted(m_id, url, null);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.loadUrl(url); }
            });
        }
    
        public void loadData(final String data, final String mimeType, final String encoding)
        {
            if (data == null)
                return;
    
            resetLoadingState(STARTED_STATE);
            c_onPageStarted(m_id, null, null);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.loadData(data, mimeType, encoding); }
            });
        }
    
        public void loadDataWithBaseURL(final String baseUrl,
                                        final String data,
                                        final String mimeType,
                                        final String encoding,
                                        final String historyUrl)
        {
            if (data == null)
                return;
    
            resetLoadingState(STARTED_STATE);
            c_onPageStarted(m_id, null, null);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.loadDataWithBaseURL(baseUrl, data, mimeType, encoding, historyUrl); }
            });
        }
    
        public void goBack()
        {
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.goBack(); }
            });
        }
    
        public boolean canGoBack()
        {
            final boolean[] back = {false};
            final Semaphore sem = new Semaphore(0);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { back[0] = m_webView.canGoBack(); sem.release(); }
            });
    
            try {
                sem.tryAcquire(BLOCKING_TIMEOUT, TimeUnit.MILLISECONDS);
            } catch (Exception e) {
                e.printStackTrace();
            }
    
            return back[0];
        }
    
        public void goForward()
        {
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.goForward(); }
            });
        }
    
        public boolean canGoForward()
        {
            final boolean[] forward = {false};
            final Semaphore sem = new Semaphore(0);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { forward[0] = m_webView.canGoForward(); sem.release(); }
            });
    
            try {
                sem.tryAcquire(BLOCKING_TIMEOUT, TimeUnit.MILLISECONDS);
            } catch (Exception e) {
                e.printStackTrace();
            }
    
            return forward[0];
        }
    
        public void stopLoading()
        {
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.stopLoading(); }
            });
        }
    
        public void reload()
        {
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { m_webView.reload(); }
            });
        }
    
        public String getTitle()
        {
            final String[] title = {""};
            final Semaphore sem = new Semaphore(0);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { title[0] = m_webView.getTitle(); sem.release(); }
            });
    
            try {
                sem.tryAcquire(BLOCKING_TIMEOUT, TimeUnit.MILLISECONDS);
            } catch (Exception e) {
                e.printStackTrace();
            }
    
            return title[0];
        }
    
        public int getProgress()
        {
            return m_progress;
        }
    
        public boolean isLoading()
        {
            return m_loadingState == LOADING_STATE || m_loadingState == STARTED_STATE || (m_progress > 0 && m_progress < 100);
        }
    
        public void runJavaScript(final String script, final long callbackId)
        {
            if (script == null)
                return;
    
            if (Build.VERSION.SDK_INT < 19 || m_webViewEvaluateJavascript == null)
                return;
    
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    try {
                        m_webViewEvaluateJavascript.invoke(m_webView, script, callbackId == -1 ? null :
                            new ValueCallback() {
                                @Override
                                public void onReceiveValue(String result) {
                                    c_onRunJavaScriptResult(m_id, callbackId, result);
                                }
                            });
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            });
        }
    
        public String getUrl()
        {
            final String[] url = {""};
            final Semaphore sem = new Semaphore(0);
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { url[0] = m_webView.getUrl(); sem.release(); }
            });
    
            try {
                sem.tryAcquire(BLOCKING_TIMEOUT, TimeUnit.MILLISECONDS);
            } catch (Exception e) {
                e.printStackTrace();
            }
    
            return url[0];
        }
    
        public WebView getWebView()
        {
           return m_webView;
        }
    
        public void onPause()
        {
            if (m_webViewOnPause == null)
                return;
    
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { try { m_webViewOnPause.invoke(m_webView); } catch (Exception e) { e.printStackTrace(); } }
            });
        }
    
        public void onResume()
        {
            if (m_webViewOnResume == null)
                return;
    
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() { try { m_webViewOnResume.invoke(m_webView); } catch (Exception e) { e.printStackTrace(); } }
            });
        }
    
        private static boolean hasLocationPermission(View view)
        {
            final String name = view.getContext().getPackageName();
            final PackageManager pm = view.getContext().getPackageManager();
            return pm.checkPermission("android.permission.ACCESS_FINE_LOCATION", name) == PackageManager.PERMISSION_GRANTED;
        }
    
        public void destroy()
        {
            m_activity.runOnUiThread(new Runnable() {
                @Override
                public void run() {
                    m_webView.destroy();
                }
            });
        }
    
        public void printToPdf(final String fileName){
            if(!busy){
                busy = true;
                m_activity.runOnUiThread(new Runnable() {
                    @Override
                    public void run() { 
                        Html2Pdf html2Pdf = new Html2Pdf();
                        html2Pdf.printToPdf(m_webView, fileName);
                    }
                });
            }else{
                c_onpdfPrintingFinished(m_id,false); 
            }
        }
    
    }

     

 

  1. 主要修改:
    1. 增加了 void printToPdf(final String fileName)打印接口
    2. 增加了 native void c_onpdfPrintingFinished(long id, boolean succeed)作为打印完成的回调
    3. 增加了内部类Html2Pdf实现打印成PDF
  • 修改$QtSrc/qtwebview/src/plugins/android/qandroidwebview_p.h
  1. 增加槽函数 void printToPdf(const QString &fileName) Q_DECL_OVERRIDE;
  • 修改$QtSrc/qtwebview/src/plugins/android/qandroidwebview.cpp
  1. 实现槽函数
    void QAndroidWebViewPrivate::printToPdf(const QString &fileName)
    {
        const QJNIObjectPrivate &fileNameString = QJNIObjectPrivate::fromString(fileName);
        m_viewController.callMethod<void>("printToPdf","(Ljava/lang/String;)V",fileNameString.object());
    }
  2. 实现java代码中打印完成的回调
    static void c_onpdfPrintingFinished(JNIEnv *env,
                                  jobject thiz,
                                  jlong id,
                                  jboolean succeed)
    {
        Q_UNUSED(env)
        Q_UNUSED(thiz)
        const WebViews &wv = (*g_webViews);
        QAndroidWebViewPrivate *wc = wv[id];
        if (!wc)
            return;
        Q_EMIT wc->pdfPrintingFinished(succeed);
    }
  3. 修改JNIEXPORT jint JNI_OnLoad(JavaVM* vm, void* /*reserved*/),注册c_onpdfPrintingFinished回调函数。
    JNINativeMethod methods[]数组里增加一项
    {"c_onpdfPrintingFinished","(JZ)V",reinterpret_cast<void *>(c_onpdfPrintingFinished)}

 

  • 修改$QtSrc/qtwebview/src/webview/qabstractwebview_p.h(以下增加的所有的C++代码、函数、信号等都用#if ANDROID宏条件编译)
  1. 增加信号void pdfPrintingFinished(bool succeed);
  • 修改$QtSrc/qtwebview/src/webview/qquickwebview_p.h
  1. 增加公开槽函数 void printToPdf(const QString &fileName) Q_DECL_OVERRIDE;
  2. 增加信号 void pdfPrintingFinished(bool succeed);
  3. 增加私有槽函数 void onPdfPrintingFinished(bool succeed);
  • 修改$QtSrc/qtwebview/src/webview/qquickwebview.cpp
  1. 构造函数里关联槽函数和信号
    #if ANDROID
    connect(m_webView, &QWebView::pdfPrintingFinished, this, &QQuickWebView::onPdfPrintingFinished);
    #endif
  2. 实现槽函数printToPdf
    #if ANDROID
    void QQuickWebView::printToPdf(const QString &fileName)
    {
        m_webView->printToPdf(fileName);
    }
    #endif
  3. 实现槽函数onPdfPrintingFinished
    #if ANDROID
    void QQuickWebView::onPdfPrintingFinished(bool succeed)
    {
        Q_EMIT pdfPrintingFinished(succeed);
    }
    #endif
  • 修改$QtSrc/qtwebview/src/webview/qwebviewinterface_p.h
  1. 增加纯虚函数 virtual void printToPdf(const QString &fileName) = 0;
  • 修改$QtSrc/qtwebview/src/webview/qwebviewfactory.cpp
  1. QNullWebView类增加
    void printToPdf(const QString &fileName) override
        {Q_UNUSED(fileName); }
  • 修改$QtSrc/qtwebview/src/webview/qwebview_p.h
  1. 增加公开槽函数 void printToPdf(const QString &fileName) Q_DECL_OVERRIDE;
  2. 增加信号 void pdfPrintingFinished(bool succeed);
  3. 增加私有槽函数 void onPdfPrintingFinished(bool succeed);
  • 修改$QtSrc/qtwebview/src/webview/qwebview.cpp
  1. 构造函数里关联槽函数和信号
    #if ANDROID
    connect(d, &QAbstractWebView::pdfPrintingFinished, this, &QWebView::onPdfPrintingFinished);
    #endif
  2. 实现槽函数printToPdf
    #if ANDROID
    void QWebView::printToPdf(const QString &fileName)
    {
        d->printToPdf(fileName);
    }
    #endif
  3. 实现槽函数onPdfPrintingFinished
    #if ANDROID
    void QWebView::onPdfPrintingFinished(bool succeed)
    {
        Q_EMIT pdfPrintingFinished(succeed);
    }
    #endif
  • 在$QtSrc/qtwebview/src/jar目录下新建lib目录,将dexmaker-1.2.jar文件拷贝到该目录下
  • 修改$QtSrc/qtwebview/src/jar/jar.pro
    TARGET = QtAndroidWebView

    load(qt_build_paths)
    CONFIG += java
    DESTDIR = $$MODULE_BASE_OUTDIR/jar

    JAVACLASSPATH += $$PWD/src \
        $$PWD/lib/dexmaker-1.2.jar

    JAVASOURCES += $$PWD/src/org/qtproject/qt5/android/view/QtAndroidWebViewController.java

    # install
    thridpartyjar.files = \
        $$PWD/lib/dexmaker-1.2.jar
    thridpartyjar.path = $$[QT_INSTALL_PREFIX]/jar

    target.path = $$[QT_INSTALL_PREFIX]/jar
    INSTALLS += target thridpartyjar
  • 修改$QtSrc/qtwebview/src/webview/webview.pro
    ……
    
    QMAKE_DOCS = \
                 $$PWD/doc/qtwebview.qdocconf

    ANDROID_BUNDLED_JAR_DEPENDENCIES = \
        jar/QtAndroidWebView.jar \
        jar/dexmaker-1.2.jar
    ANDROID_PERMISSIONS = \
        android.permission.ACCESS_FINE_LOCATION
    ANDROID_LIB_DEPENDENCIES = \
        plugins/webview/libqtwebview_android.so

    HEADERS += $$PUBLIC_HEADERS $$PRIVATE_HEADERS

    load(qt_module)
  • 修改$QtSrc/qtwebview/src/imports/plugins.qmltypes
  1. 增加信号
    Signal {
                name: "pdfPrintingFinished"
                revision: 1
                Parameter { name: "succeed"; type: "bool" }
            }
  2. 增加方法
    Method {
                name: "printToPdf"
                revision: 1
                Parameter { name: "fileName"; type: "string" }
            }
  • 配置和编译

  1. ./configure -extprefix $QTInstall/android_arm64_v8a -xplatform android-clang -release -nomake tests -nomake examples -opensource -confirm-license -recheck-all -android-ndk $NDKPATH -android-sdk $AndroidSDKPATH -android-ndk-host linux-x86_64 -android-arch arm64-v8a
    -android-arch支持armeabi, armeabi-v7a, arm64-v8a, x86, x86_64,一次只能编译一个架构,注意不同架构要修改安装目录
  2. make -j8
  3. make install
  • 上述软件版本
  1. QT:5.13.2
  2. NDK:r20b(20.1.5948944)
  3. Android-buildToolsVersion:29.0.2
  • 使用示例
    import QtQuick 2.12
    import QtQuick.Window 2.12
    import QtWebView 1.1
    import QtQuick.Controls 2.12
    
    Window {
        id: window
        visible: true
        width: 1080
        height: 1920
        title: qsTr("Hello World")
        WebView{
            id:webView
            anchors.bottom: printBtn.top
            anchors.right: parent.right
            anchors.left: parent.left
            anchors.top: parent.top
            anchors.bottomMargin: 0
            url:"http://www.qq.com"
            onPdfPrintingFinished: {
                printBtn.text = "打印" + (succeed?"成功":"失败")
                printBtn.enabled = true
            }
        }
    
        Button {
            id:printBtn
            text: "打印"
            anchors.bottom: parent.bottom
            anchors.bottomMargin: 0
            onClicked: {
                printBtn.enabled = false
                webView.printToPdf("/sdcard/aaa.pdf")
            }
        }
    }

全部修改见https://github.com/ALittleDruid/qtwebview/commit/722a4757dd0acf86846194607a433cd724e9b028

下期预告:在Android平台上实现串口读写的功能

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