js画图开发库--mxgraph--[control-缩放(放大、缩小).html]
<!Doctype html>
<html xmlns=http://www.w3.org/1999/xhtml>
<head>
<meta http-equiv=Content-Type content="text/html;charset=utf-8">
<title>缩放</title>
<!-- 如果本文件的包与src不是在同一个目录,就要将basepath设置到src目录下 -->
<script type="text/javascript">
mxBasePath = '../src';
</script>
<!-- 引入支持库文件 -->
<script type="text/javascript" src="../src/js/mxClient.js"></script>
<!-- 示例代码 -->
<script type="text/javascript">
// 程序在此方法中启动
function main(container) {
// 检查浏览器支持
if (!mxClient.isBrowserSupported()) {
mxUtils.error('Browser is not supported!', 200, false);
} else {
//去锯齿效果
mxRectangleShape.prototype.crisp = true;
// 在容器中创建图形
var graph = new mxGraph(container);
graph.setPanning(true);
// 删除图标
var deleteImage = new mxImage('editors/images/overlays/forbidden.png', 16, 16);
// 重写以添加一个删除按钮
mxCellRendererCreateControl = mxCellRenderer.prototype.createControl;
mxCellRenderer.prototype.createControl = function(state) {
mxCellRendererCreateControl.apply(this, arguments);
var graph = state.view.graph;
if (graph.getModel().isVertex(state.cell))
{
if (state.deleteControl == null)
{
var b = new mxRectangle(0, 0, deleteImage.width, deleteImage.height);
state.deleteControl = new mxImageShape(b, deleteImage.src);
state.deleteControl.dialect = graph.dialect;
state.deleteControl.preserveImageAspect = false;
this.initControl(state, state.deleteControl, false, function (evt)
{
if (graph.isEnabled())
{
graph.removeCells([state.cell]);
mxEvent.consume(evt);
}
});
}
}
else if (state.deleteControl != null)
{
state.deleteControl.destroy();
state.deleteControl = null;
}
};
// 辅助函数来计算元素边界
var getDeleteControlBounds = function(state)
{
if (state.deleteControl != null)
{
var oldScale = state.deleteControl.scale;
var w = state.deleteControl.bounds.width / oldScale;
var h = state.deleteControl.bounds.height / oldScale;
var s = state.view.scale;
return (state.view.graph.getModel().isEdge(state.cell)) ?
new mxRectangle(state.x + state.width / 2 - w / 2 * s,
state.y + state.height / 2 - h / 2 * s, w * s, h * s)
: new mxRectangle(state.x + state.width - w * s,
state.y, w * s, h * s);
}
return null;
};
// 重写以更新大小状态
mxCellRendererRedrawControl = mxCellRenderer.prototype.redrawControl;
mxCellRenderer.prototype.redrawControl = function(state)
{
mxCellRendererRedrawControl.apply(this, arguments);
if (state.deleteControl != null)
{
var bounds = getDeleteControlBounds(state);
var s = state.view.scale;
if (state.deleteControl.scale != s || !state.deleteControl.bounds.equals(bounds))
{
state.deleteControl.bounds = bounds;
state.deleteControl.scale = s;
state.deleteControl.redraw();
}
}
};
// 如果状态被破坏，重写中删除控制
mxCellRendererDestroy = mxCellRenderer.prototype.destroy;
mxCellRenderer.prototype.destroy = function(state) {
mxCellRendererDestroy.apply(this, arguments);
if (state.deleteControl != null)
{
state.deleteControl.destroy();
state.deleteControl = null;
}
};
//设置容器自动调整大小
//graph.setResizeContainer(true);
// 拉伸选项
new mxRubberband(graph);
// 在对象中创建默认组件
var parent = graph.getDefaultParent();
//开启模型的更新事务
graph.getModel().beginUpdate();
try
{
var v1 = graph.insertVertex(parent, null, 'Hello,', 20, 20, 80, 30);
var v2 = graph.insertVertex(parent, null, 'World!', 200, 150, 80, 30);
var e1 = graph.insertEdge(parent, null, '', v1, v2);
}
finally {
// 更新事务结束
graph.getModel().endUpdate();
}
//是否已图形的中心进行放大，否则以元素为中心放大
graph.centerZoom = false;
//添加放大和缩小按钮
document.body.appendChild(mxUtils.button('Zoom In（放大）', function() {
graph.zoomIn();
}));
document.body.appendChild(mxUtils.button('Zoom Out（缩小）', function() {
graph.zoomOut();
}));
}
};
</script>
</head>
<!-- 页面载入时启动程序 -->
<body onload="main(document.getElementById('graphContainer'))">
<!-- 创建带网格壁纸和曲线的一个容器 -->
<div id="graphContainer"
style="overflow:hidden;width:621px;height:441px;background:url('editors/images/grid.gif');cursor:default;">
</div>
</body>
</html>