From bf2e4567055d3ecc9939323549f293a1ef7e5c69 Mon Sep 17 00:00:00 2001
From: Cagatay Civici <cagatay.civici@gmail.com>
Date: Thu, 13 May 2021 17:14:52 +0300
Subject: [PATCH] Fixed #396 - Scrollable Tree

---
 src/assets/menu/menu.json         |   4 +
 src/components/tree/Tree.d.ts     |   1 +
 src/components/tree/Tree.vue      |  34 ++++-
 src/router/index.js               |   5 +
 src/views/tree/TreeDoc.vue        |  24 ++++
 src/views/tree/TreeScrollDemo.vue | 217 ++++++++++++++++++++++++++++++
 6 files changed, 279 insertions(+), 6 deletions(-)
 create mode 100644 src/views/tree/TreeScrollDemo.vue

diff --git a/src/assets/menu/menu.json b/src/assets/menu/menu.json
index eea2e8587..f1d7e1619 100644
--- a/src/assets/menu/menu.json
+++ b/src/assets/menu/menu.json
@@ -459,6 +459,10 @@
                         {
                             "name": "Filter",
                             "to": "/tree/filter"
+                        },
+                        {
+                            "name": "Scroll",
+                            "to": "/tree/scroll"
                         }
                     ]
                 },
diff --git a/src/components/tree/Tree.d.ts b/src/components/tree/Tree.d.ts
index c4dfbc275..897c97a05 100755
--- a/src/components/tree/Tree.d.ts
+++ b/src/components/tree/Tree.d.ts
@@ -13,6 +13,7 @@ interface TreeProps {
     filterMode?: string;
     filterPlaceholder?: string;
     filterLocale?: string;
+    scrollHeight?: string;
 }
 
 declare class Tree {
diff --git a/src/components/tree/Tree.vue b/src/components/tree/Tree.vue
index 0cf4fc83e..06b0c55d4 100755
--- a/src/components/tree/Tree.vue
+++ b/src/components/tree/Tree.vue
@@ -10,11 +10,13 @@
                 @keydown="onFilterKeydown" v-model="filterValue" />
             <span class="p-tree-filter-icon pi pi-search"></span>
         </div>
-        <ul class="p-tree-container" role="tree">
-            <TreeNode v-for="node of valueToRender" :key="node.key" :node="node" :templates="$slots"
-                :expandedKeys="d_expandedKeys" @node-toggle="onNodeToggle" @node-click="onNodeClick"
-                :selectionMode="selectionMode" :selectionKeys="selectionKeys" @checkbox-change="onCheckboxChange"></TreeNode>
-        </ul>
+        <div class="p-tree-wrapper" :style="{maxHeight: scrollHeight}">
+            <ul class="p-tree-container" role="tree">
+                <TreeNode v-for="node of valueToRender" :key="node.key" :node="node" :templates="$slots"
+                    :expandedKeys="d_expandedKeys" @node-toggle="onNodeToggle" @node-click="onNodeClick"
+                    :selectionMode="selectionMode" :selectionKeys="selectionKeys" @checkbox-change="onCheckboxChange"></TreeNode>
+            </ul>
+        </div>
     </div>
 </template>
 
@@ -73,6 +75,10 @@ export default {
         filterLocale: {
             type: String,
             default: undefined
+        },
+        scrollHeight: {
+            type: String,
+            default: null
         }
     },
     data() {
@@ -243,7 +249,8 @@ export default {
         containerClass() {
             return ['p-tree p-component', {
                 'p-tree-selectable': this.selectionMode != null,
-                'p-tree-loading': this.loading
+                'p-tree-loading': this.loading,
+                'p-tree-flex-scrollable': this.scrollHeight === 'flex'
             }];
         },
         loadingIconClass() {
@@ -294,6 +301,10 @@ export default {
     list-style-type: none;
 }
 
+.p-tree-wrapper {
+    overflow: auto;
+}
+
 .p-treenode-selectable {
     cursor: pointer;
     user-select: none;
@@ -346,4 +357,15 @@ export default {
     align-items: center;
     justify-content: center;
 }
+
+.p-tree-flex-scrollable {
+    display: flex;
+    flex: 1;
+    height: 100%;
+    flex-direction: column;
+}
+
+.p-tree-flex-scrollable .p-tree-wrapper {
+    flex: 1;
+}
 </style>
diff --git a/src/router/index.js b/src/router/index.js
index d482f0934..f0d9f2340 100644
--- a/src/router/index.js
+++ b/src/router/index.js
@@ -706,6 +706,11 @@ const routes = [
         name: 'treefilter',
         component: () => import('../views/tree/TreeFilterDemo.vue')
     },
+    {
+        path: '/tree/scroll',
+        name: 'treescroll',
+        component: () => import('../views/tree/TreeScrollDemo.vue')
+    },
     {
         path: '/treeselect',
         name: 'treeselect',
diff --git a/src/views/tree/TreeDoc.vue b/src/views/tree/TreeDoc.vue
index 7803065fb..23221fd12 100755
--- a/src/views/tree/TreeDoc.vue
+++ b/src/views/tree/TreeDoc.vue
@@ -486,6 +486,30 @@ export default {
     }
 }
 
+</code></pre>
+
+                <h5>Scrolling</h5>
+                <p>Scrolling is used to preserve space as content of the tree is dynamic and enabled by <i>scrollHeight</i> property.</p>
+<pre v-code><code><template v-pre>
+&lt;Tree :value="nodes1" scrollHeight="200px"&gt;&lt;/Tree&gt;
+</template>
+</code></pre>
+
+                <h5>Flex Scroll</h5>
+                <p>In cases where viewport should adjust itself according to the table parent's height instead of a fixed viewport height, set <i>scrollHeight</i> option as <b>flex</b>. In example below,
+                table is inside a Dialog where viewport size dynamically responds to the dialog size changes such as maximizing.</p>
+
+<pre v-code><code><template v-pre>
+&lt;Button type="button" icon="pi pi-external-link" label="View" @click="dialogVisible = true"&gt;&lt;/Button&gt;
+
+&lt;Dialog header="Flex Scroll" v-model:visible="dialogVisible" :style="{width: '50vw'}" maximizable
+    :contentStyle="{height: '300px'}" class="p-fluid"&gt;
+    &lt;Tree :value="nodes2" scrollHeight="flex"&gt;&lt;/Tree&gt;
+    &lt;template #footer&gt;
+        &lt;Button type="button" icon="pi pi-check" @click="dialogVisible = false" class="p-button-text"&gt;&lt;/Button&gt;
+    &lt;/template&gt;
+&lt;/Dialog&gt;
+</template>
 </code></pre>
 
         <h5>Filtering</h5>
diff --git a/src/views/tree/TreeScrollDemo.vue b/src/views/tree/TreeScrollDemo.vue
new file mode 100644
index 000000000..9165182d3
--- /dev/null
+++ b/src/views/tree/TreeScrollDemo.vue
@@ -0,0 +1,217 @@
+<template>
+    <div>
+        <div class="content-section introduction">
+            <div class="feature-intro">
+                <h1>Tree <span>Scroll</span></h1>
+                <p>Scrolling is used to preserve space in cases when rendering large data.</p>
+            </div>
+            <AppDemoActions />
+        </div>
+
+        <div class="content-section implementation">
+            <div class="card">
+                <h5>Regular Scroll</h5>
+                <p>Scrollable viewport is fixed.</p>
+                <Tree :value="nodes1" scrollHeight="200px"></Tree>
+
+                <h5>Flex Scroll</h5>
+                <p>Flex scroll feature makes the scrollable viewport section dynamic so that it can grow or shrink relative to the parent size of the tree. Click the button below
+                to display maximizable Dialog where data viewport adjusts itself according to the size changes.</p>
+                <Button type="button" icon="pi pi-external-link" label="View" @click="dialogVisible = true"></Button>
+
+                <Dialog header="Flex Scroll" v-model:visible="dialogVisible" :style="{width: '50vw'}" maximizable
+                    :contentStyle="{height: '300px'}" class="p-fluid">
+                    <Tree :value="nodes2" scrollHeight="flex"></Tree>
+                    <template #footer>
+                        <Button type="button" icon="pi pi-check" @click="dialogVisible = false" class="p-button-text"></Button>
+                    </template>
+                </Dialog>
+            </div>
+        </div>
+
+        <AppDoc name="TreeScrollDemo" :sources="sources" :service="['NodeService']" :data="['treenodes']" github="tree/TreeScrollDemo.vue" />
+    </div>
+</template>
+
+<script>
+import NodeService from '../../service/NodeService';
+
+export default {
+    data() {
+        return {
+            nodes1: null,
+            nodes2: null,
+            dialogVisible: false,
+            sources: {
+                'options-api': {
+                    tabName: 'Options API Source',
+                    content: `
+<template>
+    <div>
+        <h5>Regular Scroll</h5>
+        <p>Scrollable viewport is fixed.</p>
+        <Tree :value="nodes1" scrollHeight="200px"></Tree>
+
+        <h5>Flex Scroll</h5>
+        <p>Flex scroll feature makes the scrollable viewport section dynamic so that it can grow or shrink relative to the parent size of the tree. Click the button below
+        to display maximizable Dialog where data viewport adjusts itself according to the size changes.</p>
+        <Button type="button" icon="pi pi-external-link" label="View" @click="dialogVisible = true"></Button>
+
+        <Dialog header="Flex Scroll" v-model:visible="dialogVisible" :style="{width: '50vw'}" maximizable
+            :contentStyle="{height: '300px'}" class="p-fluid">
+            <Tree :value="nodes2" scrollHeight="flex"></Tree>
+            <template #footer>
+                <Button type="button" icon="pi pi-check" @click="dialogVisible = false" class="p-button-text"></Button>
+            </template>
+        </Dialog>
+    </div>
+</template>
+
+<script>
+import NodeService from './service/NodeService';
+
+export default {
+    data() {
+        return {
+            nodes1: null,
+            nodes2: null,
+            dialogVisible: false
+        }
+    },
+    nodeService: null,
+    created() {
+        this.nodeService = new NodeService();
+    },
+    mounted() {
+        this.nodeService.getTreeNodes().then(data => this.nodes1 = data);
+        this.nodes2 = Array.from({length: 100}).map((_,i) => this.createNode(i, 2));
+    },
+    methods: {
+        createNode(i, children) {
+            let node = {
+                key: 'node_' + i,
+                label: 'Node ' + i,
+                data: 'Node ' + i,
+                expandedIcon: 'pi pi-folder-open',
+                collapsedIcon: 'pi pi-folder',
+                children: Array.from({length: children}).map((_,j) => {
+                    return {
+                        label: 'Node ' + i + '.' + j, 
+                        data: 'Node ' + i + '.' + j, 
+                        icon: 'pi pi-file-o'
+                    }
+                })
+            };
+
+            return node;
+        }
+    }
+}
+<\\/script>
+`
+                },
+                'composition-api': {
+                    tabName: 'Composition API Source',
+                    content: `
+<template>
+    <div>
+        <h5>Regular Scroll</h5>
+        <p>Scrollable viewport is fixed.</p>
+        <Tree :value="nodes1" scrollHeight="200px"></Tree>
+
+        <h5>Flex Scroll</h5>
+        <p>Flex scroll feature makes the scrollable viewport section dynamic so that it can grow or shrink relative to the parent size of the tree. Click the button below
+        to display maximizable Dialog where data viewport adjusts itself according to the size changes.</p>
+        <Button type="button" icon="pi pi-external-link" label="View" @click="dialogVisible = true"></Button>
+
+        <Dialog header="Flex Scroll" v-model:visible="dialogVisible" :style="{width: '50vw'}" :maximizable="true"
+            :contentStyle="{height: '300px'}" class="p-fluid">
+            <Tree :value="nodes2" scrollHeight="flex"></Tree>
+            <template #footer>
+                <Button type="button" icon="pi pi-check" @click="dialogVisible = false" class="p-button-text"></Button>
+            </template>
+        </Dialog>
+    </div>
+</template>
+
+<script>
+import { ref, onMounted } from 'vue';
+import { useToast } from 'primevue/usetoast';
+import NodeService from './service/NodeService';
+
+export default {
+    setup() {
+        const createNode = (i, children) => {
+            let node = {
+                key: 'node_' + i,
+                label: 'Node ' + i,
+                data: 'Node ' + i,
+                expandedIcon: 'pi pi-folder-open',
+                collapsedIcon: 'pi pi-folder',
+                children: Array.from({length: children}).map((_,j) => {
+                    return {
+                        label: 'Node ' + i + '.' + j, 
+                        data: 'Node ' + i + '.' + j, 
+                        icon: 'pi pi-file-o'
+                    }
+                })
+            };
+
+            return node;
+        }
+
+        onMounted(() => {
+            nodeService.value.getTreeNodes().then(data => nodes.value = data);
+            nodes2.value = Array.from({length: 100}).map((_,i) => createNode(i, 2));
+        })
+
+        const nodes1 = ref(null);
+        const nodes2 = ref(null);
+        const dialogVisible = ref(false);
+        const nodeService = ref(new NodeService());
+
+        return { nodes1, nodes2, dialogVisible }
+    }
+}
+<\\/script>`
+
+                }
+            }
+        }
+    },
+    nodeService: null,
+    created() {
+        this.nodeService = new NodeService();
+    },
+    mounted() {
+        this.nodeService.getTreeNodes().then(data => this.nodes1 = data);
+        this.nodes2 = Array.from({length: 100}).map((_,i) => this.createNode(i, 2));
+    },
+    methods: {
+        createNode(i, children) {
+            let node = {
+                key: 'node_' + i,
+                label: 'Node ' + i,
+                data: 'Node ' + i,
+                expandedIcon: 'pi pi-folder-open',
+                collapsedIcon: 'pi pi-folder',
+                children: Array.from({length: children}).map((_,j) => {
+                    return {
+                        label: 'Node ' + i + '.' + j, 
+                        data: 'Node ' + i + '.' + j, 
+                        icon: 'pi pi-file-o'
+                    }
+                })
+            };
+
+            return node;
+        }
+    }
+}
+</script>
+
+<style scoped>
+button {
+    margin-right: .5rem;
+}
+</style>
\ No newline at end of file