tips: Qt5 call android static function

最新推荐文章于 2022-05-02 11:01:30 发布

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本文介绍如何在Qt中集成Android特定功能，包括配置Qt项目文件以包含Android组件、手动编辑AndroidManifest.xml文件来添加权限及指定活动名称，并提供通过Java代码实现获取WiFi列表的具体示例。

1. ?.pro file add:

QT += qml quick androidextras


ANDROID_PACKAGE_SOURCE_DIR = $$PWD/android-sources

OTHER_FILES += \
    android-sources/AndroidManifest.xml \
    android-sources/src/org/qtproject/qmhp/AndroidCodeMhp.java

2. gen AndroidManifest.xml file; add premission

AndroidManifest.xml file in "Xml Source" window , make a change by hand.

default activity name is "qt.project.qt5.example.bindings.qtActivity" cause qt don't know your java class name, should be change by hand.

following is a example:

AndroidManifest.xml:

<?xml version="1.0"?>

<manifest package="org.qtproject.qmhp" xmlns:android="http://schemas.android.com/apk/res/android" android:versionName="1.0" android:versionCode="1" android:installLocation="auto">

    <application android:hardwareAccelerated="true" android:name="org.qtproject.qt5.android.bindings.QtApplication" android:label="Qmhp" android:icon="@drawable/icon">

        <activity android:configChanges="orientation|uiMode|screenLayout|screenSize|smallestScreenSize|locale|fontScale|keyboard|keyboardHidden|navigation" android:name="org.qtproject.qmhp.AndroidCodeMhp" android:label="@string/app_name" android:screenOrientation="unspecified" android:launchMode="singleTop">

package: org.qtproject.qmhp

java File name: AndroidCodeMhp.java

java Class : AndroidCodeMhp

3. qt5 can only call static java function for now.

example java code(get wifi list):

package org.qtproject.qmhp;

import org.qtproject.qt5.android.bindings.QtActivity;
import org.qtproject.qt5.android.bindings.QtApplication;

import java.lang.String;

import java.util.List;

import android.util.Log;

import android.content.Context;

import android.net.wifi.WifiManager;

import android.net.wifi.WifiInfo;

import android.net.wifi.ScanResult;

public class AndroidCodeMhp extends QtActivity

    private static AndroidCodeMhp m_instance;

    private static WifiManager m_wifiManager = null;

    private static WifiInfo m_wifiInfo = null;

    private static List<ScanResult>  m_wifiList;

    	public AndroidCodeMhp()

        m_instance = this;

// WIFI

    public static String getWifi(int nu) {

        if (m_wifiManager == null) {

            m_wifiManager = (WifiManager) m_instance.getSystemService(Context.WIFI_SERVICE);

        m_wifiManager.setWifiEnabled(true);

        m_wifiInfo = m_wifiManager.getConnectionInfo();

        return getWifiInfo();

    public static String getWifiList(int nu){

        if (m_wifiManager == null) {

            m_wifiManager = (WifiManager) m_instance.getSystemService(Context.WIFI_SERVICE);

        m_wifiManager.setWifiEnabled(true);

        m_wifiManager.startScan();

         m_wifiList= m_wifiManager.getScanResults();

        if ( m_wifiList.size() == 0){

                    return "n/a";

        String string = new String();

        for (int i = 0; i <  m_wifiList.size(); i++) {

            string += (( m_wifiList.get(i)).toString());

            string += ";";

        return string;

    public static String getWifiInfo() {

        return (m_wifiInfo == null) ? "NULL" : m_wifiInfo.toString();

...

4. call from qt like following:

there is a bug, the function must have parameter, other else noting will return.

the following parameter "22" is not used, but when I use "(V)Ljava/lang/String;" got nothing;

#include <QtAndroidExtras/QAndroidJniObject>

...

    QAndroidJniObject androidString=

    QAndroidJniObject::callStaticObjectMethod(

                "org/qtproject/qmhp/AndroidCodeMhp",

                                              "getWifiList",

                                              "(I)Ljava/lang/String;",

                                              22);

    m_androidWifiData = androidString.toString();

...

qt call android did work, but must be careful.