fix scrolling

src/app/pages/chat/group-messages/group-messages.page.html

@@ -39,7 +39,7 @@
       <ion-label>Esta conversa passou a grupo</ion-label><br />
       <ion-label>A conversa original mantêm-se como chat individual</ion-label>
     </div>
-    <div *ngFor="let msg of messages" >
+    <div *ngFor="let msg of messages; let last = last" >
       <div *ngIf="msg.t != 'r'" class='incoming-{{msg.u.username!=loggedUser.me.username}}'>
         <div class="title">
           <ion-label>{{msg.u.name}}</ion-label>
@@ -47,6 +47,7 @@
         </div>
         <div>
           <ion-label>{{msg.msg}}</ion-label>
+          {{last ? scrollToBottom() : ''}}
         </div>
       </div>
       <div *ngIf="msg.t == 'r'" class="info-text">

src/app/pages/chat/group-messages/group-messages.page.ts

@@ -1,4 +1,4 @@
-import { Component, ElementRef, OnInit, ViewChild, AfterViewChecked } from '@angular/core';
+import { Component, ElementRef, OnInit, ViewChild, AfterViewChecked, AfterViewInit, OnDestroy } from '@angular/core';
 import { ActionSheetController, MenuController, ModalController, NavParams, PopoverController } from '@ionic/angular';
 import { AlertService } from 'src/app/services/alert.service';
 import { AuthService } from 'src/app/services/auth.service';
@@ -16,7 +16,7 @@ import { EditGroupPage } from '../edit-group/edit-group.page';
   templateUrl: './group-messages.page.html',
   styleUrls: ['./group-messages.page.scss'],
 })
-export class GroupMessagesPage implements OnInit, AfterViewChecked {
+export class GroupMessagesPage implements OnInit, AfterViewInit, OnDestroy {
   showLoader: boolean;
   isGroupCreated:boolean;
   loggedUser: any;
@@ -33,6 +33,11 @@ export class GroupMessagesPage implements OnInit, AfterViewChecked {
   loggedUserChat:any;
   eventSelectedDate: Date = new Date();
 
+  scrollingOnce:boolean = true;
+  private scrollChangeCallback: () => void;
+  currentPosition: any;
+  startPosition: number;
+
   @ViewChild('scrollMe') private myScrollContainer: ElementRef;
 
   constructor(
@@ -57,15 +62,48 @@ export class GroupMessagesPage implements OnInit, AfterViewChecked {
     this.getRoomInfo();
     this.scrollToBottom();
     this.serverLongPull();
+    this.setStatus('online');
   }
 
-  ngAfterViewChecked() {
-    //this.scrollToBottom();
+  setStatus(status:string){
+    let body = {
+      message: '',
+      status: status,
+    }
+    this.chatService.setUserStatus(body).subscribe(res => {
+      console.log(res);
+    })
+  }
+
+  ngAfterViewInit() {
+    this.scrollChangeCallback = () => this.onContentScrolled(event);
+    window.addEventListener('scroll', this.scrollChangeCallback, true);
+  }
+
+   onContentScrolled(e) {
+    this.startPosition = e.srcElement.scrollTop;
+    let scroll = e.srcElement.scrollTop;
+    if (scroll > this.currentPosition) {
+      //this.showButton = false;
+      //alert('BOTTOM');
+    } else {
+      //this.showButton = true;
+      //alert('UP');
+      this.scrollingOnce = false;
+    }
+    this.currentPosition = scroll;
+  }
+
+  ngOnDestroy() {
+    window.removeEventListener('scroll', this.scrollChangeCallback, true);
   }
 
   scrollToBottom(): void {
     try {
-      this.myScrollContainer.nativeElement.scrollTop = this.myScrollContainer.nativeElement.scrollHeight;
+      if(this.scrollingOnce){
+        this.myScrollContainer.nativeElement.scrollTop = this.myScrollContainer.nativeElement.scrollHeight;
+        //this.scrollingOnce = false;
+      }
     } catch(err) { }
   }
 
@@ -181,6 +219,7 @@ export class GroupMessagesPage implements OnInit, AfterViewChecked {
 
     this.chatService.sendMessage(body).subscribe(res=> {
       this.getRoomInfo();
+      this.scrollingOnce = true;
 
     },(error) => {
 
@@ -302,7 +341,8 @@ export class GroupMessagesPage implements OnInit, AfterViewChecked {
       // Show Error
       //showMessage(response.statusText);
       //this.loadMessages()
-      this.messages = res['messages'].filter(data => data.t != 'au');
+      let msgOnly = res['messages'].filter(data => data.t != 'au');
+      this.messages = msgOnly.reverse();
       console.log(this.messages);
       // Reconnect in one second
       if(this.route.url != "/home/chat"){