fix: fix iframe heigth error (#1012)

src/views/sys/iframe/index.vue

 <template>
   <div :class="prefixCls" :style="getWrapStyle">
     <Spin :spinning="loading" size="large" :style="getWrapStyle">
-      <iframe :src="frameSrc" :class="`${prefixCls}__main`" ref="frameRef"></iframe>
+      <iframe
+        :src="frameSrc"
+        :class="`${prefixCls}__main`"
+        ref="frameRef"
+        @load="hideLoading"
+      ></iframe>
     </Spin>
   </div>
 </template>
 <script lang="ts">
   import type { CSSProperties } from 'vue';
-  import { defineComponent, ref, unref, onMounted, nextTick, computed } from 'vue';
+  import { defineComponent, ref, unref, computed } from 'vue';
   import { Spin } from 'ant-design-vue';
 
-  import { getViewportOffset } from '/@/utils/domUtils';
-
   import { useWindowSizeFn } from '/@/hooks/event/useWindowSizeFn';
 
   import { propTypes } from '/@/utils/propTypes';
   import { useDesign } from '/@/hooks/web/useDesign';
+  import { useLayoutHeight } from '/@/layouts/default/content/useContentViewHeight';
 
   export default defineComponent({
     name: 'IFrame',
@@ -24,10 +28,11 @@
       frameSrc: propTypes.string.def(''),
     },
     setup() {
-      const loading = ref(false);
+      const loading = ref(true);
       const topRef = ref(50);
       const heightRef = ref(window.innerHeight);
-      const frameRef = ref<HTMLFrameElement | null>(null);
+      const frameRef = ref<HTMLFrameElement>();
+      const { headerHeightRef } = useLayoutHeight();
 
       const { prefixCls } = useDesign('iframe-page');
       useWindowSizeFn(calcHeight, 150, { immediate: true });
@@ -43,8 +48,7 @@
         if (!iframe) {
           return;
         }
-        let { top } = getViewportOffset(iframe);
-        top += 20;
+        const top = headerHeightRef.value;
         topRef.value = top;
         heightRef.value = window.innerHeight - top;
         const clientHeight = document.documentElement.clientHeight - top;
@@ -56,33 +60,13 @@
         calcHeight();
       }
 
-      function init() {
-        nextTick(() => {
-          const iframe = unref(frameRef);
-          if (!iframe) return;
-
-          const _frame = iframe as any;
-          if (_frame.attachEvent) {
-            _frame.attachEvent('onload', () => {
-              hideLoading();
-            });
-          } else {
-            iframe.onload = () => {
-              hideLoading();
-            };
-          }
-        });
-      }
-      onMounted(() => {
-        loading.value = true;
-        init();
-      });
-
       return {
         getWrapStyle,
         loading,
         frameRef,
         prefixCls,
+
+        hideLoading,
       };
     },
   });