Merge pull request #137 from gurupras/1.x

Added virtualLines prop to control number of visible lines

Author: Daniel

README.md

@@ -112,6 +112,7 @@ plugins: [
 | showDoubleQuotes         | normal | Whether to show doublequotes on key                                                     | boolean                                        | true     |
 | virtual                  | normal | Whether to use virtual scrolling, usually used for big data                             | boolean                                        | false    |
 | itemHeight               | normal | The height of each item when using virtual scrolling                                    | number                                         | auto     |
+| virtualLines             | normal | The number of lines to render when virtual scrolling is enabled                         | number                                         | 10       |
 | v-model                  | higher | Defines value when the tree can be selected                                             | string, array                                  | -        |
 | path                     | higher | Root data path                                                                          | string                                         | root     |
 | pathSelectable           | higher | Defines whether a data path supports selection                                          | function(path, content)                        | -        |

src/components/Tree/index.vue

@@ -127,6 +127,11 @@ export default {
       type: Function,
       default: null,
     },
+    // Number of lines to show when virtual is true
+    virtualLines: {
+      type: Number,
+      default: 10
+    }
   },
   data() {
     return {
@@ -217,7 +222,7 @@ export default {
   methods: {
     onTreeScroll() {
       if (this.virtual) {
-        const visibleCount = 10;
+        const visibleCount = this.virtualLines;
         const scrollTop = (this.$refs.tree && this.$refs.tree.scrollTop) || 0;
         const scrollCount = Math.floor(scrollTop / this.itemHeight);
         let start =