Remove OnGlobalLayoutListener after first run

It's only supposed to run once and it will cause performance issues if
it's continuously run

mastodon/src/main/java/org/joinmastodon/android/fragments/HomeTabFragment.java

@@ -233,28 +233,36 @@ public void onPageSelected(int position){
 
 		ViewTreeObserver vto = getToolbar().getViewTreeObserver();
 		if (vto.isAlive()) {
-			vto.addOnGlobalLayoutListener(()->{
-				Toolbar t=getToolbar();
-				if(t==null) return;
-				int toolbarWidth=t.getWidth();
-				if(toolbarWidth==0) return;
-
-				int toolbarFrameWidth=toolbarFrame.getWidth();
-				int actionsWidth=toolbarWidth-toolbarFrameWidth;
-				// margin (4) + padding (12) + icon (24) + margin (8) + chevron (16) + padding (12)
-				int switcherWidth=V.dp(76);
-				FrameLayout parent=((FrameLayout) toolbarShowNewPostsBtn.getParent());
-				if(actionsWidth==parent.getPaddingStart()) return;
-				int paddingMax=Math.max(actionsWidth, switcherWidth);
-				int paddingEnd=(Math.max(0, switcherWidth-actionsWidth));
-
-				// toolbar frame goes from screen edge to beginning of right-aligned option buttons.
-				// centering button by applying the same space on the left
-				parent.setPaddingRelative(paddingMax, 0, paddingEnd, 0);
-				toolbarShowNewPostsBtn.setMaxWidth(toolbarWidth-paddingMax*2);
-
-				switcher.setPivotX(V.dp(28)); // padding + half of icon
-				switcher.setPivotY(switcher.getHeight() / 2f);
+			vto.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener(){
+				@Override
+				public void onGlobalLayout(){
+					Toolbar t=getToolbar();
+					if(t==null) return;
+					int toolbarWidth=t.getWidth();
+					if(toolbarWidth==0) return;
+
+					int toolbarFrameWidth=toolbarFrame.getWidth();
+					int actionsWidth=toolbarWidth-toolbarFrameWidth;
+					// margin (4) + padding (12) + icon (24) + margin (8) + chevron (16) + padding (12)
+					int switcherWidth=V.dp(76);
+					FrameLayout parent=((FrameLayout) toolbarShowNewPostsBtn.getParent());
+					if(actionsWidth==parent.getPaddingStart()) return;
+					int paddingMax=Math.max(actionsWidth, switcherWidth);
+					int paddingEnd=(Math.max(0, switcherWidth-actionsWidth));
+
+					// toolbar frame goes from screen edge to beginning of right-aligned option buttons.
+					// centering button by applying the same space on the left
+					parent.setPaddingRelative(paddingMax, 0, paddingEnd, 0);
+					toolbarShowNewPostsBtn.setMaxWidth(toolbarWidth-paddingMax*2);
+
+					switcher.setPivotX(V.dp(28)); // padding + half of icon
+					switcher.setPivotY(switcher.getHeight() / 2f);
+
+					ViewTreeObserver vto = getToolbar().getViewTreeObserver();
+					if (vto.isAlive()){
+						vto.removeOnGlobalLayoutListener(this);
+					}
+				}
 			});
 		}