我正在尝试使用ol.interaction.Draw
将多边形添加到开放图层地图中。我还打开了 Snap 交互,并设置为在按住 shift 时关闭。
const
snapInteraction = new ol.interaction.Snap({
source: drawLayer.getSource()
}),
turnOnSnap = (evt) => {
if (!isShiftKey(evt)) {
return;
}
console.log('shift key is down, turning off snap');
snapInteraction.setActive(false);
},
turnOffSnap = (evt) => {
if (!isShiftKey(evt)) {
return;
}
console.log('shift key is up, turning on snap');
snapInteraction.setActive(true);
};
document.addEventListener('keydown', turnOnSnap);
document.addEventListener('keyup', turnOffSnap);
这适用于禁用捕捉。但是,当我按住 shift 时,我的绘制交互不起作用。我知道condition
参数默认为ol.events.condition.noModifierKeys
,但是当我进行自定义condition
时,它甚至永远不会被击中!
const drawInteraction = new ol.interaction.Draw({
source: drawLayer.getSource(),
type: 'Polygon',
condition: function (evt) {
console.log("yo, why isn't this hit when I hold down shift?", evt);
return (ol.events.condition.noModifierKeys(evt) ||
ol.events.condition.shiftKeyOnly(evt));
}
});
为什么绘图交互忽略 shift+click 事件?
freehandCondition
的默认值是捕获 shift+click 事件,因此永远不会对它们进行condition
评估。将其更改为其他内容,Shift+单击事件将命中您的自定义条件函数。
const drawInteraction = new ol.interaction.Draw({
source: drawLayer.getSource(),
type: 'Polygon',
condition: function (evt) {
return (ol.events.condition.noModifierKeys(evt) ||
ol.events.condition.shiftKeyOnly(evt));
},
freehandCondition: ol.events.condition.never, // <-- add this line
});