本文基于腾讯课堂老胡的课《跟我学Openlayers--基础实例详解》做的学习笔记，使用的openlayers 5.3.x api。
源码 见 1022.html ，对应的 官网示例 https://openlayers.org/en/latest/apidoc/module-ol_layer_Layer-Layer.html
image.png
image.png
<!DOCTYPE html>
<html>
<head>
<title>控制图层位置关系
</title>
<link rel="stylesheet" href="../include/ol.css" type="text/css">
<script src="../include/ol.js"></script>
<script src="../include/jquery-3.1.1.min.js"></script>
</head>
<style>
#layertree li>span {
cursor: pointer;
}
</style>
<body>
<div>
<label for="idx1">
<input type="number" id="idx1"></input>
方块所在图层的 Z-index
</label></br>
<label for="idx2">
<input type="number" id="idx2"></input>
三角形所在图层的 Z-index
</label>
</div>
<div id="map" class="map"></div>
<script>
var stroke = new ol.style.Stroke({ color: 'black', width: 1 });
//设置图层的样式，三角形 五角星 矩形
var styles = {
'square': new ol.style.Style({
image: new ol.style.RegularShape({
fill: new ol.style.Fill({ color: 'blue' }),
stroke: stroke,
points: 4,
radius: 80,
angle: Math.PI / 4
})
}),
'triangle': new ol.style.Style({
image: new ol.style.RegularShape({
fill: new ol.style.Fill({ color: 'red' }),
stroke: stroke,
points: 3,
radius: 80,
rotation: Math.PI / 4,
angle: 0
})
}),
'star': new ol.style.Style({
image: new ol.style.RegularShape({
fill: new ol.style.Fill({ color: 'green' }),
stroke: stroke,
points: 5,
radius: 80,
radius2: 4,
angle: 0
})
})
};
//动态创建图层
function createLayer(coordinates, style, zIndex) {
var feature = new ol.Feature(new ol.geom.Point(coordinates));
feature.setStyle(style);
var source = new ol.source.Vector({
features: [feature]
});
var vectorLayer = new ol.layer.Vector({
source: source
});
vectorLayer.setZIndex(zIndex);
return vectorLayer;
}
var layer0 = createLayer([40, 40], styles['star'], 0);
var layer1 = createLayer([0, 0], styles['square'], 1);
var layer2 = createLayer([0, 40], styles['triangle'], 0);
//使用动态方法，把图层增加到图层组中
var layers = [];
layers.push(layer1);
layers.push(layer2);
layers.push(layer0);
var map = new ol.Map({
layers: layers,
target: 'map',
view: new ol.View({
center: [0, 0],
zoom: 18
})
});
//动态改变dom对象的属性ZIndex
function bindInputs(id, layer) {
var idxInput = document.getElementById('idx' + id);
idxInput.onchange = function () {
layer.setZIndex(parseInt(this.value, 10) || 0); //当输入新的值时，改变图层的属性ZIndex
};
idxInput.value = String(layer.getZIndex());
}
bindInputs(1, layer1);
bindInputs(2, layer2);
</script>
</body>
</html>
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