javascript - 同步Window.show()

Question

在我的项目中，我使用从 Window 派生的自定义组件来显示消息。目前我使用这段代码:

function showMessage(title, text) {
    var component = Qt.createComponent("MessageBox.qml");
    if (component.status === Component.Ready) {
        var dialog = component.createObject(parent);
        dialog.caption = title;
        dialog.message = text;
        dialog.show();
        return dialog;
    }
}

但现在我想将它用作 JS 中的 confirm() ，即现在它应该等到用户单击对话框中的相应按钮，然后返回值(true/false) .

所需的用途之一是验证用户表单，例如:

function checkAForm() {
    if(!showMessage("Warning","The field f1 is empty. Do you want to continue?"))
        return false;
    if(!showMessage("Warning","Some warning"))
        return false;
    if(!showMessage("Warning","Some another warning"))
        return false;
    return true;
}

现在这个函数总是同时打开 3 个窗口并返回 false。

第一个想法是通过信号连接来实现:

function checkAForm() {
    var dialog1 = showMessage("...","...");
    dialog1.accepted.connect(function(){
        var dialog2 = showMessage("...","...");
        dialog2.accepted.connect(function(){
            var dialog3 = showMessage("...","...");
            dialog3.accepted.connect(function(){
                return true;
            });
        });
    });
}

其中accepted是用户单击Ok按钮时发出的MessageBox.qml信号。

但是这个结构太复杂而且不太清晰。另外我不知道如果使用点击取消该怎么办。

所以现在我正在寻找如何实现 Window.show() 同步调用的好主意，或者可能是其他一些想法，也许是一些信号量或类似的东西。

Answer 1

据我迄今为止从评论中了解到的，似乎同步/异步(GUI线程是否阻塞)可能不是这里的问题，但你想按顺序有多个对话框窗口，这在我看来有点像一个巫师。

为此，按照您当前的方法，为什么不做这样的事情:

首先，您将像这样设置自定义 MessageBox.qml:

Item {
...
    property var acceptedFunction
    property var canceledFunction
...
    Button {
        id: acceptedButton
        onClicked: { acceptedFunction() }
    }
    Button {
        id: canceledButton
        onClicked: { canceledFunction() }
    }
...
}

然后，在使用qml中:

    function startTheShow() {
        showFirstWindow()
    }

    function showFirstWindow() {
        var title = "First Window's Title"
        var text = "First Window's Text"
        var component = Qt.createComponent("MessageBox.qml");
        if (component.status === Component.Ready) {
            var dialog = component.createObject(parent);
            dialog.caption = title;
            dialog.message = text;
            dialog.acceptedFunction = showSecondWindow
            dialog.canceledFunction = function() { ...do something here... } //This is just for an example how you can have it also -- as an anonymous function.
            dialog.show();
        }
    }

    function showSecondWindow() {
        var title = "Second Window's Title"
        var text = "Second Window's Text"
        var component = Qt.createComponent("MessageBox.qml");
        if (component.status === Component.Ready) {
            var dialog = component.createObject(parent);
            dialog.caption = title;
            dialog.message = text;
            dialog.acceptedFunction = showThirdWindow
            dialog.canceledFunction = function() { ...do something here... } //This is just for an example how you can have it also -- as an anonymous function.
            dialog.show();
        }

    function showThirdWindow() ...and so on

如果您摆弄上面的东西，您也可以使用一个通用函数和一组对象作为窗口流的配置来完成它。也许是这样的:

MessageBox.qml:

Item {
...
    property int myIndex
    property var showNextWindowFunc
    Button {
        id: acceptedButton
        onClicked: { showNextWindowFunc(myIndex+1) }
    }
    Button {
        id: canceledButton
        onClicked: { ...do some standard thing perhaps?... }
    }
...
}

利用Qml.qml:

property var myWindowSequenceConfiguration: [
    { "title" : "Title 1", "text" : "Text 1" },
    { "title" : "Title 2", "text" : "Text 2" },
    ...
]

function showWindow(index) {
    var component = Qt.createComponent("MessageBox.qml");
    if (component.status === Component.Ready) {
        var dialog = component.createObject(parent);
        dialog.myIndex = index
        dialog.caption = myWindowSequenceConfiguration[index]["title"];
        dialog.message = myWindowSequenceConfiguration[index]["text"];
        dialog.showNextWindowFunc = showWindow
        dialog.show();
    }
}

function startTheShow() {
    showWindow(0)
}

---

好吧，我想出了主题的另一个变体:

MessageBox.qml:

Item {
...
    property var acceptedFuncParams
    property var canceledFuncParams
    property var acceptedFunc
    property var canceledFunc
    Button {
        id: acceptedButton
        onClicked: { acceptedFunc(acceptedFuncParams) }
    }
    Button {
        id: canceledButton
        onClicked: { canceledFunc(canceledFuncParams) }
    }
...
}

利用Qml.qml:

property var myWindowSequenceConfiguration: [
    { "title" : "Title 1", "text" : "Text 1" },
    { "title" : "Title 2", "text" : "Text 2" },
    ...
]

function showWindow(index) {
    var component = Qt.createComponent("MessageBox.qml");
    if (component.status === Component.Ready) {
        var dialog = component.createObject(parent);
        dialog.caption = myWindowSequenceConfiguration[index]["title"];
        dialog.message = myWindowSequenceConfiguration[index]["text"];
        dialog.acceptedFuncParams = index+1
        dialog.acceptedFunc = showWindow
        dialog.canceledFunc = function() { ...do something here... }
        dialog.show();
    }
}

function startTheShow() {
    showWindow(0)
}