<template>
  <div>
    <h1>插入/删除节点、前进回退</h1>
<p>首先和操作节点内容一样，也需要监听节点的激活事件，然后禁用相关按钮。</p>
<h2>插入子节点</h2>
<p>插入子节点很节点，执行<code>INSERT_CHILD_NODE</code>命令即可：</p>
<pre class="hljs"><code>mindMap.execCommand(<span class="hljs-string">&#x27;INSERT_CHILD_NODE&#x27;</span>)
</code></pre>
<p>这样就会在当前激活节点（如果存在多个激活节点，默认会操作第一个激活节点）下添加一个子节点。</p>
<p><code>INSERT_CHILD_NODE</code>命令还支持传入几个参数，详细详细请阅读【API】-【构造函数】-【execCommand方法】。</p>
<h2>插入兄弟节点</h2>
<p>插入兄弟节点和插入子节点方式完全一致：</p>
<pre class="hljs"><code>mindMap.execCommand(<span class="hljs-string">&#x27;INSERT_NODE&#x27;</span>)
</code></pre>
<h2>删除节点</h2>
<p>删除节点也是执行命令：</p>
<pre class="hljs"><code>mindMap.execCommand(<span class="hljs-string">&#x27;REMOVE_NODE&#x27;</span>)
</code></pre>
<p>会删除当前激活的所有节点。</p>
<h2>前进回退</h2>
<p>首先需要监听<code>back_forward</code>事件，事件回调中可以获取当前的历史记录总数，以及当前所在的历史记录索引，那么就可以判断当前是否处于历史记录的最开始，还是最后，然后对前进回退按钮进行禁用。</p>
<pre class="hljs"><code><span class="hljs-keyword">const</span> isStart = ref(<span class="hljs-literal">true</span>)
<span class="hljs-keyword">const</span> isEnd = ref(<span class="hljs-literal">true</span>)
mindMap.on(<span class="hljs-string">&#x27;back_forward&#x27;</span>, <span class="hljs-function">(<span class="hljs-params">index, len</span>) =&gt;</span> {
    isStart.value = index &lt;= <span class="hljs-number">0</span>
    isEnd.value = index &gt;= len - <span class="hljs-number">1</span>
})
</code></pre>
<p>然后前进回退调用相关命令即可：</p>
<pre class="hljs"><code><span class="hljs-comment">// 回退一次</span>
mindMap.execCommand(<span class="hljs-string">&#x27;BACK&#x27;</span>)

<span class="hljs-comment">// 前进一次</span>
mindMap.execCommand(<span class="hljs-string">&#x27;FORWARD&#x27;</span>)
</code></pre>
<h2>完整示例</h2>
<iframe style="width: 100%; height: 455px; border: none;" src="https://wanglin2.github.io/playground/#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" />
  </div>
</template>

<script>
export default {

}
</script>

<style>

</style>