import QtQuick 2.6;
import QtQuick.Controls 2.1 ;
import QtQuick.Layouts 1.3 ;
Page{
id: page
width: 800
height: 1024
background: Rectangle {
color: "black" ;
anchors.fill:parent ;
}
Rectangle {
id:rect1
x: 0
y:10
width: 100
height: 100
color : "red"
MouseArea {
anchors.fill: parent
onClicked: tmr.restart()
}
}
Rectangle {
id:rect2
x: 0
y:110
width: 100
height: 100
color : "blue"
MouseArea {
anchors.fill: parent
onClicked: tmr.restart()
}
}
Timer {
id : tmr
interval : 30000
repeat : true
running: true
onTriggered: {
console.log ("hello world ")
}
}
}
我使用 qt 框架为嵌入式 imx6 飞思卡尔设备开发了一个软件。
基本上，我只想在每次单击以及每次在屏幕上收到触摸事件时重新启动我的计时器，无论单击/触摸发生在矩形的鼠标区域内部还是外部。
这个想法类似于屏幕保护程序。
最佳答案
有多种方法，正确的方法取决于您的要求。
如果您不需要保证计时器在输入期间触发，您可以在所有内容之上放置一个 MouseArea。在这个 MouseArea 中，你处理 pressed 信号，但不要 accept 它们。
这允许您稍后处理较低层中的鼠标输入。但是，您只有在发生新的新闻时才会意识到，并且 Timer 可能会触发，例如在半小时的手指移动输入期间。
第二种方法是让所有 MouseArea 报告它们处理的信号，信号发生了，以重置 Timer 。对于所有未处理的信号，您将 MouseArea 置于其他所有信号之下，处理那里的所有信号以捕捉已落下的信号。
诉诸 C++，您可能会在 Item 树的根目录创建一个 Item，并覆盖 childMouseEventFitler有关更多信息，请参阅我的回答 here。
在这种情况下，你应该在这个 MouseArea 中添加一个 Item ，这样它就可以在任何地方过滤。
感谢 GrecKo，我再次查看了一般的 eventFilter，确实很容易。
QObject，在其中重新实现 eventFilter -方法，以便它发出信号 mouseeventspy.h
#pragma once
#include <QObject>
#include <QtQml>
#include <QQmlEngine>
#include <QJSEngine>
class MouseEventSpy : public QObject
{
Q_OBJECT
public:
explicit MouseEventSpy(QObject *parent = 0);
static MouseEventSpy* instance();
static QObject* singletonProvider(QQmlEngine* engine, QJSEngine* script);
protected:
bool eventFilter(QObject* watched, QEvent* event);
signals:
void mouseEventDetected(/*Pass meaningfull information to QML?*/);
};
mouseeventspy.cpp
#include "mouseeventspy.h"
#include <QQmlEngine>
#include <QJSEngine>
#include <QEvent>
MouseEventSpy::MouseEventSpy(QObject *parent) : QObject(parent)
{
qDebug() << "created Instance";
}
// This implements the SINGLETON PATTERN (*usually evil*)
// so you can get the instance in C++
MouseEventSpy* MouseEventSpy::instance()
{
static MouseEventSpy* inst;
if (inst == nullptr)
{
// If no instance has been created yet, creat a new and install it as event filter.
// Uppon first use of the instance, it will automatically
// install itself in the QGuiApplication
inst = new MouseEventSpy();
QGuiApplication* app = qGuiApp;
app->installEventFilter(inst);
}
return inst;
}
// This is the method to fullfill the signature required by
// qmlRegisterSingletonType.
QObject* MouseEventSpy::singletonProvider(QQmlEngine *, QJSEngine *)
{
return MouseEventSpy::instance();
}
// This is the method is necessary for 'installEventFilter'
bool MouseEventSpy::eventFilter(QObject* watched, QEvent* event)
{
QEvent::Type t = event->type();
if ((t == QEvent::MouseButtonDblClick
|| t == QEvent::MouseButtonPress
|| t == QEvent::MouseButtonRelease
|| t == QEvent::MouseMove)
&& event->spontaneous() // Take only mouse events from outside of Qt
)
emit mouseEventDetected();
return QObject::eventFilter(watched, event);
}
main.cpp
#include <QGuiApplication>
#include <QQmlApplicationEngine>
#include "mouseeventspy.h"
int main(int argc, char *argv[])
{
QGuiApplication app(argc, argv);
QQmlApplicationEngine engine;
qmlRegisterSingletonType<MouseEventSpy>("MouseEventSpy", 1, 0, "MouseEventSpy", MouseEventSpy::singletonProvider);
// We do this now uppon creation of the first instance.
// app.installEventFilter(MouseEventSpy::instance());
engine.load(QUrl(QStringLiteral("main.qml")));
return app.exec();
}
Timer main.qml
import QtQuick 2.6
import QtQuick.Window 2.2
import MouseEventSpy 1.0
Window {
visible: true
width: 640
height: 480
title: qsTr("Hello World")
Connections {
target: MouseEventSpy
onMouseEventDetected: myTimer.restart()
}
Timer {
id: myTimer
interval: 1000
onTriggered: console.log('It has been 1 seconds since the last mouse event')
}
Text {
anchors.center: parent
text: myTimer.running ? 'Timer is Running\nMove the mouse to reset'
: 'Move the Mouse to make the timer run again.'
}
}