统一聊天页的头像大小，改用rpx2px的计算，84rpx

pages/im/group/chat.vue

@@ -7,7 +7,7 @@
                 <view class="cell" v-for="(item, index) in messages" :key="index">
                     <view class="time" v-if="item.senderUserId === '__system__'">{{ item.content.message }}</view>
                     <view v-else :class="['cell-item', item.messageDirection == 1 ? 'right' : 'left']">
-                        <u-avatar class="avatar" @click="toUser(item)" size="36" shape="square"
+                        <u-avatar class="avatar" @click="toUser(item)" :size="avatarSize" shape="square"
                             :src="contact(item.senderUserId).portraitUrl" />
                         <view class="msg">
                             <show-voice v-if="item.objectName === 'RC:HQVCMsg'" :guest="item.messageDirection == 1"
@@ -37,6 +37,7 @@
     import showImage from '../components/showImage'
     import showText from '../components/showText'
     import sentMessageBar from '../components/sentMessageBar'
+    import utils from '@/utils/index.js'
 
     export default {
         components: {
@@ -47,6 +48,7 @@
         },
         data() {
             return {
+                avatarRpx: 84,
                 targetId: '',
                 conversationType: RongIMLib.ConversationType.GROUP,
                 messages: [],
@@ -56,6 +58,9 @@
             }
         },
         computed: {
+            avatarSize() {
+                return utils.rpx2px(this.avatarRpx)
+            },
             latestMessage() {
                 if (this.messages.length) {
                     return this.messages[0]
@@ -74,8 +79,8 @@
         onLoad(e) {
             this.targetId = e.targetId
             // 获取群成员数量
-            getGroupBase(this.targetId).then(res => {
-                console.log(res);
+            getGroupBase(this.targetId).then(res => {
+                console.log(res);
                 uni.setNavigationBarTitle({
                     title: res.name + `(${res.members})`
                 })
@@ -174,6 +179,7 @@
 
                 .cell {
                     padding: 10rpx 30rpx;
+
                     .time {
                         text-align: center;
                         font-size: 24rpx;