# JS Objects
While working with JS there are some objects and methods which are more frequently used. This is a small collection of them.
Math.floor(v),Math.ceil(v),Math.round(v)- largest, smallest, rounded integer from floatMath.random()- create a random number between 0 and 1Object.keys(o)- get keys from object (including QObject)JSON.parse(s),JSON.stringify(o)- conversion between JS object and JSON stringNumber.toFixed(p)- fixed precision floatDate- Date manipulation
You can find them also at: JavaScript reference (opens new window)
Here some small and limited examples of how to use JS with QML. They should give you an idea how you can use JS inside QML
# Print all keys from QML Item
Item {
id: root
Component.onCompleted: {
var keys = Object.keys(root);
for(var i=0; i<keys.length; i++) {
var key = keys[i];
// prints all properties, signals, functions from object
console.log(key + ' : ' + root[key]);
}
}
}
# Parse an object to a JSON string and back
Item {
property var obj: {
key: 'value'
}
Component.onCompleted: {
var data = JSON.stringify(obj);
console.log(data);
var obj = JSON.parse(data);
console.log(obj.key); // > 'value'
}
}
# Current Date
Item {
Timer {
id: timeUpdater
interval: 100
running: true
repeat: true
onTriggered: {
var d = new Date();
console.log(d.getSeconds());
}
}
}
# Call a function by name
Item {
id: root
function doIt() {
console.log("doIt()")
}
Component.onCompleted: {
// Call using function execution
root["doIt"]();
var fn = root["doIt"];
// Call using JS call method (could pass in a custom this object and arguments)
fn.call()
}
}
