luaengineapp/src/luaengineapp/edit.lua

--[[
******************************************************************************
* luaEngine Lua Engine for Qt
* Copyright (C) 2018 Syping
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*     http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************
--]]

local currentFile
local mainWindow
local textEditor

function main()
    mainWindow = createMainWindow("LE Text Editor")
    local mainWidget = createCentralWidget(mainWindow)
    local mainLayout = createLayout(VerticalLayout, mainWidget)
    setLayoutMargins(mainLayout, 0, 0, 0, 0)

    local menuBar = createMenuBar(mainWindow)
    local menuFile = createMenu("&File", menuBar)
    local menuEntryNew = createMenuEntry("&New", menuFile)
    setMenuShortcut(menuEntryNew, "Ctrl+N")
    connect(menuEntryNew, "triggered()", "editorNew")
    local menuEntryOpen = createMenuEntry("&Open...", menuFile)
    setMenuShortcut(menuEntryOpen, "Ctrl+O")
    connect(menuEntryOpen, "triggered()", "editorOpen")
    local menuEntrySave = createMenuEntry("&Save...", menuFile)
    setMenuShortcut(menuEntrySave, "Ctrl+S")
    connect(menuEntrySave, "triggered()", "editorSave")
    local menuEntrySaveAs = createMenuEntry("Save &as...", menuFile)
    connect(menuEntrySaveAs, "triggered()", "editorSaveAs")
    createMenuSeparator(menuFile)
    local menuEntryExit = createMenuEntry("&Exit", menuFile)
    setMenuShortcut(menuEntryExit, "Alt+F4")
    connect(menuEntryExit, "triggered()", "editorClose")
    local menuHelp = createMenu("&Help", menuBar)
    local menuEntryAbout = createMenuEntry("&About LE Text Editor", menuHelp)
    setMenuShortcut(menuEntryAbout, "Ctrl+P")
    connect(menuEntryAbout, "triggered()", "editorAboutBox")

    textEditor = createPlainTextEdit("", mainWidget)
    layoutAddWidget(mainLayout, textEditor)

    setWidgetSize(mainWindow, 650, 450)
    showWidget(mainWindow, ShowDefault)
    return GuiExecuted
end

function editorNew()
    setWidgetText(textEditor, "")
    currentFile = nil
end

function editorOpen()
    local selectedFile = showFileDialog(OpenFileDialog, "Open...", "All files (*)", mainWindow)
    if not (selectedFile == nil) then
        local file = io.open(selectedFile, "r")
        if not (file == nil) then
            local content = file:read("*a")
            setWidgetText(textEditor, content)
            file:close()
            currentFile = selectedFile
        else
            showMessageBox(WarningMessageBox, "Failed to open file " .. selectedFile .. "!", "Open...", mainWindow)
        end
    end
end

function editorSave()
    if not (currentFile == nil) then
        local file = io.open(currentFile, "w")
        if not (file == nil) then
            editorSaveFile(file)
        else
            showMessageBox(WarningMessageBox, "Failed to save file " .. currentFile .. "!", "Save...", mainWindow)
        end
    else
        editorSaveAs()
    end
end

function editorSaveAs()
    local selectedFile = showFileDialog(SaveFileDialog, "Save as...", "All files (*)", mainWindow)
    if not (selectedFile == nil) then
        local file = io.open(selectedFile, "w")
        if not (file == nil) then
            editorSaveFile(file)
            currentFile = selectedFile
        else
            showMessageBox(WarningMessageBox, "Failed to save file " .. selectedFile .. "!", "Save as...", mainWindow)
        end
    end
end

function editorSaveFile(file)
    file:write(getWidgetText(textEditor))
    file:close()
end

function editorAboutBox()
    local dialog = createDialog("About LE Text Editor", mainWindow)
    local dialogLayout = createLayout(VerticalLayout, dialog)
    local dialogLabel = createLabel("<h4>LE Text Editor</h4>A simple Text Editor made in Lua Engine", dialog)
    layoutAddWidget(dialogLayout, dialogLabel)
    local buttonLayout = createLayout(HorizontalLayout, dialogLayout)
    createSpacerItem(SizePolicyExpanding, SizePolicyMinimum, buttonLayout)
    local dialogButton = createPushButton("&OK", dialog)
    layoutAddWidget(buttonLayout, dialogButton)
    connect(dialogButton, "clicked()", "closeDialog")
    setWidgetFixed(dialog)
    executeWidget(dialog)
    delete(dialog, DeleteInstant)
end

function editorClose()
    closeWidget(mainWindow)
end

function closeDialog(pushButton)
    disconnect(pushButton, "clicked()")
    closeWidget(getWindow(pushButton))
end