Photo gallery in iOS and Android

guidupas

Hello!

I am developing an app for mobile to run in iOS and Android and I am facing some difficulties to access the photo gallery of the devices with Qt and Qml.

Could someone help me to figure out how I can do that?

Thanks a lot.

SGaist

Hi,

IIRC, QFileDialog handles that for iOS but I don't remember the state for Android

guidupas

I am developing an app for mobile to run in iOS and Android and I am facing some difficulties to access the image gallery of the devices with Qml.

I need to list the images from the image gallery in a GridView.

I have tried to return the pictures folder using QStandardPaths but it just works for desktop computers. For smartphones running iOS and Android it returns a folder that is not the folder of the gallery.

Could someone help me to figure out how I can do that? My code is below:

main.cpp

#include <QGuiApplication>
#include <QQmlApplicationEngine>

#include <QtQml>

#include "caminhoimagens.h"

int main(int argc, char *argv[])
{
    QGuiApplication app(argc, argv);

    qmlRegisterType<caminhoImagens>("PathImagens", 1, 0, "CaminhoImagens");

    QQmlApplicationEngine engine;
    engine.load(QUrl(QStringLiteral("qrc:/main.qml")));

    return app.exec();
}

main.qml

import QtQuick 2.4
import QtQuick.Window 2.2
import QtQuick.Controls 1.3
import QtQuick.Dialogs 1.2

import Qt.labs.folderlistmodel 2.1

import PathImagens 1.0

Window {
    visible: true

    width: 360
    height: 640

    maximumHeight: 640
    minimumHeight: 640

    maximumWidth: 360
    minimumWidth: 360

    title: "Acessar Galeria Test"

    Rectangle {
        id: principal

        anchors.fill: parent

        ListModel {
            id: listModel
        }

        FolderListModel {
            id: folderListModel

            folder: "file://" + caminhoImagens.retornaCaminhoImagens()
            nameFilters: "*.jpeg"
        }

        CaminhoImagens {
            id: caminhoImagens
        }

        Item {
            id: listaFotosDelegate

            property Component delegateComponent: listaFotosDelegateComponent

            Component {
                id: listaFotosDelegateComponent

                Image {
                    id: imagem

                    source: folderListModel.folder + "/" + fileName

                    width: principal.width / 4.2
                    height: principal.width / 4.2

                    fillMode: Image.PreserveAspectCrop
                }
            }
        }

        GridView {
            id: listaFotosGridView

            anchors.fill: parent

            clip: true

            model: folderListModel

            delegate: listaFotosDelegate.delegateComponent

            cellWidth: parent.width / 4
            cellHeight: parent.width / 4
        }
    }
}

caminhoimagens.h

#ifndef CAMINHOIMAGENS_H
#define CAMINHOIMAGENS_H

#include <QObject>
#include <QStandardPaths>

class caminhoImagens : public QObject
{
    Q_OBJECT

public slots:
    QString retornaCaminhoImagens();

public:
    caminhoImagens();
};

#endif // CAMINHOIMAGENS_H

caminhoimagens.cpp

#include "caminhoimagens.h"

caminhoImagens::caminhoImagens()
{

}

QString caminhoImagens::retornaCaminhoImagens()
{
    return QStandardPaths::locate(QStandardPaths::PicturesLocation, QString(), QStandardPaths::LocateDirectory);
}

amahta

@guidupas You can checkout this post on how to access image gallery in Qt using JNI but I am not so sure how you can apply it to QML.

guidupas

Thanks for the reply @amahta

I am doing that with QAndroidJniObject to write a equivalent code with Qt

My problem now is that I am trying to get the MediaStore columns using QAndroidJniObject because the path returned is a reference to a column position like this /document/image:30

Do you know how can I get the columns of MediaStore using QAndroidJniObject?

benlau

@guidupas

If you mean to get the parameter of columns array to content resolver. You may try this code: (Didn't tested)

QAndroidJniObject data = QAndroidJniObject::getStaticObjectField("android/provider/MediaStore$Images$Media","Data");

btw, what you need to do it in JNI? I think it is just too troublesome.

guidupas

@benlau I need to geed an image from gallery and sent it to QML
Take a look at this post
https://forum.qt.io/topic/61539/qt-and-android-gallery-mediastore-using-qandroidjniobject

benlau

I mean why don't you just code in Java.

Moreover, I think the signature should be "android/provider/MediaStore$Images$Media"

guidupas

@benlau , I think it's easier to handle with the activity in Qt.
Could you help me to solve the problem of the previous post link?

guidupas

Solved

Here is the code to get the full image path from android gallery using java equivalent code written with Qt:

#include "imagepickerandroid.h"

imagePickerAndroid::imagePickerAndroid()
{

}

void imagePickerAndroid::buscaImagem()
{
    QAndroidJniObject ACTION_PICK = QAndroidJniObject::getStaticObjectField("android/content/Intent", "ACTION_PICK", "Ljava/lang/String;");
    QAndroidJniObject EXTERNAL_CONTENT_URI = QAndroidJniObject::getStaticObjectField("android/provider/MediaStore$Images$Media", "EXTERNAL_CONTENT_URI", "Landroid/net/Uri;");

    QAndroidJniObject intent=QAndroidJniObject("android/content/Intent", "(Ljava/lang/String;Landroid/net/Uri;)V", ACTION_PICK.object<jstring>(), EXTERNAL_CONTENT_URI.object<jobject>());

    if (ACTION_PICK.isValid() && intent.isValid())
    {
        intent.callObjectMethod("setType", "(Ljava/lang/String;)Landroid/content/Intent;", QAndroidJniObject::fromString("image/*").object<jstring>());
        QtAndroid::startActivity(intent.object<jobject>(), 101, this);
        qDebug() << "OK";
    }
    else
    {
        qDebug() << "ERRO";
    }
}

void imagePickerAndroid::handleActivityResult(int receiverRequestCode, int resultCode, const QAndroidJniObject &data)
{
    jint RESULT_OK = QAndroidJniObject::getStaticField<jint>("android/app/Activity", "RESULT_OK");
    if (receiverRequestCode == 101 && resultCode == RESULT_OK)
    {
        QAndroidJniObject uri = data.callObjectMethod("getData", "()Landroid/net/Uri;");
        QAndroidJniObject dadosAndroid = QAndroidJniObject::getStaticObjectField("android/provider/MediaStore$MediaColumns", "DATA", "Ljava/lang/String;");
        QAndroidJniEnvironment env;
        jobjectArray projecao = (jobjectArray)env->NewObjectArray(1, env->FindClass("java/lang/String"), NULL);
        jobject projacaoDadosAndroid = env->NewStringUTF(dadosAndroid.toString().toStdString().c_str());
        env->SetObjectArrayElement(projecao, 0, projacaoDadosAndroid);
        QAndroidJniObject contentResolver = QtAndroid::androidActivity().callObjectMethod("getContentResolver", "()Landroid/content/ContentResolver;");
        QAndroidJniObject cursor = contentResolver.callObjectMethod("query", "(Landroid/net/Uri;[Ljava/lang/String;Ljava/lang/String;[Ljava/lang/String;Ljava/lang/String;)Landroid/database/Cursor;", uri.object<jobject>(), projecao, NULL, NULL, NULL);
        jint columnIndex = cursor.callMethod<jint>("getColumnIndex", "(Ljava/lang/String;)I", dadosAndroid.object<jstring>());
        cursor.callMethod<jboolean>("moveToFirst", "()Z");
        QAndroidJniObject resultado = cursor.callObjectMethod("getString", "(I)Ljava/lang/String;", columnIndex);
        QString imagemCaminho = "file://" + resultado.toString();
        emit imagemCaminhoSignal(imagemCaminho);
    }
    else
    {
        qDebug() << "Caminho errado";
    }
}