add book

Qt6QMLBeginnersCode/13-Storage/5-SQLite/CMakeLists.txt

@@ -0,0 +1,40 @@
+# Copyright (c) Daniel Gakwaya.
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.16)
+
+project(5-SQLite VERSION 0.1 LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+
+find_package(Qt6 6.5 REQUIRED COMPONENTS Quick QuickControls2)
+
+qt_standard_project_setup(REQUIRES 6.5)
+
+qt_add_executable(app5-SQLite
+    main.cpp
+)
+
+qt_add_qml_module(app5-SQLite
+    URI 5-SQLite
+    VERSION 1.0
+    QML_FILES Main.qml Database.js
+)
+
+set_target_properties(app5-SQLite PROPERTIES
+    MACOSX_BUNDLE_GUI_IDENTIFIER my.example.com
+    MACOSX_BUNDLE_BUNDLE_VERSION ${PROJECT_VERSION}
+    MACOSX_BUNDLE_SHORT_VERSION_STRING ${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}
+    MACOSX_BUNDLE TRUE
+    WIN32_EXECUTABLE TRUE
+)
+
+target_link_libraries(app5-SQLite
+    PRIVATE Qt6::Quick Qt6::QuickControls2
+)
+
+install(TARGETS app5-SQLite
+    BUNDLE DESTINATION .
+    LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR}
+    RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR}
+)

Qt6QMLBeginnersCode/13-Storage/5-SQLite/Database.js

@@ -0,0 +1,79 @@
+// Copyright (c) Daniel Gakwaya.
+// SPDX-License-Identifier: MIT
+
+function dbInit(){
+    console.log(" Initializing database...")
+
+    db = LocalStorage.openDatabaseSync("sqlitedemodb", "1.0", "SQLite Demo database", 100000);
+    db.transaction( function(tx) {
+        print('... create table')
+        tx.executeSql('CREATE TABLE IF NOT EXISTS sqlitedemotable(name TEXT, value TEXT)');
+    });
+}
+
+
+function storeData(){
+    console.log(" Storing data...")
+
+    //Check if the database was ever created
+    if (!db){
+        return ;
+    }
+
+    db.transaction(function(tx){
+        //Check if sqlitedemo entry is available in database table
+        var result = tx.executeSql('SELECT * from sqlitedemotable where name = "sqlitedemo"');
+
+        //Prepare json object data from qml code
+        var obj = { x: rootId.x, y: rootId.y,
+            width : rootId.width,height : rootId.height,
+            colorred : rectId.color.r,colorgreen : rectId.color.g ,
+            colorblue : rectId.color.b };
+
+        if ( result.rows.length ===1 ){
+            //Update
+            console.log("Updating database table...")
+            result = tx.executeSql('UPDATE sqlitedemotable set value=? where name="sqlitedemo"',
+                                    [JSON.stringify(obj)])
+        }else{
+            //Create entry
+            console.log("Creating new database table entry")
+            result = tx.executeSql('INSERT INTO sqlitedemotable VALUES (?,?)',
+                                    ['sqlitedemo', JSON.stringify(obj)])
+        }
+
+    });
+
+}
+
+
+function readData(){
+    console.log(" Reading data...")
+
+    if (!db){
+        return ;
+    }
+
+    db.transaction( function(tx) {
+        print('... Reading data from database')
+        var result = tx.executeSql('select * from sqlitedemotable where name="sqlitedemo"');
+
+        if(result.rows.length === 1){
+            //We have data that we can work  with
+
+            // get the value column
+            var value = result.rows[0].value;
+            // convert to JS object
+            var obj = JSON.parse(value)
+
+            // apply to object
+            rootId.x = obj.x;
+            rootId.y = obj.y;
+            rootId.width= obj.width;
+            rootId.height = obj.height
+            rectId.color= Qt.rgba(obj.colorred,obj.colorgreen,obj.colorblue,1)
+        }
+
+    });
+
+}

Qt6QMLBeginnersCode/13-Storage/5-SQLite/Main.qml

@@ -0,0 +1,51 @@
+// Copyright (c) Daniel Gakwaya.
+// SPDX-License-Identifier: MIT
+
+import QtQuick
+import QtQuick.LocalStorage
+import QtQuick.Dialogs
+import "Database.js" as JS
+
+Window {
+    id: rootId
+    visible: true
+    width: 640
+    height: 480
+    title: qsTr("SQLite")
+    property var db ;
+
+    Rectangle{
+        id: rectId
+        anchors.fill: parent
+        color: "red"
+
+        MouseArea{
+            anchors.fill: parent
+            onClicked: {
+                colorDialogId.open()
+            }
+
+            ColorDialog {
+                id: colorDialogId
+                title: "Please choose a color"
+                onAccepted: {
+                    console.log("The new color is: "+ selectedColor)
+                    rectId.color = selectedColor
+                }
+                onRejected: {
+                    console.log("Canceled")
+                }
+            }
+        }
+    }
+
+    Component.onCompleted: {
+        //Read data
+        JS.dbInit()
+        JS.readData()
+    }
+
+    Component.onDestruction: {
+        JS.storeData()
+    }
+}

Qt6QMLBeginnersCode/13-Storage/5-SQLite/main.cpp

@@ -0,0 +1,22 @@
+// Copyright (c) Daniel Gakwaya.
+// SPDX-License-Identifier: MIT
+
+#include <QGuiApplication>
+#include <QQmlApplicationEngine>
+#include <QQuickStyle>
+
+
+int main(int argc, char *argv[])
+{
+
+    QGuiApplication app(argc, argv);
+    QQuickStyle::setStyle("Basic");
+
+    QQmlApplicationEngine engine;
+    QObject::connect(&engine, &QQmlApplicationEngine::objectCreationFailed,
+        &app, []() { QCoreApplication::exit(-1); },
+        Qt::QueuedConnection);
+    engine.loadFromModule("5-SQLite", "Main");
+
+    return app.exec();
+}