Merge branch 'master' of https://github.com/Mantano/AndroidLibs into Mantano-master

# Conflicts:
#	flowlayoutmanager/build.gradle
#	flowlayoutmanager/src/main/java/com/xiaofeng/flowlayoutmanager/FlowLayoutManager.java

Author: simonebortolin

flowlayoutmanager/build.gradle

@@ -12,6 +12,10 @@ project.ext {
     siteUrl = 'https://github.com/xiaofeng-han/AndroidLibs'
 }
 
+repositories {
+    jcenter()
+}
+
 group = 'com.xiaofeng.android'
 version = libVersion
 
@@ -48,7 +52,13 @@ dependencies {
     compile(group: 'com.android.support', name: 'recyclerview-v7', version: supportLibVersion)
     androidTestCompile 'com.android.support:support-annotations:26.1.0'
     androidTestCompile 'com.android.support.test:runner:1.0.1'
+
 }
 
 Properties properties = new Properties()
 properties.load(project.rootProject.file('local.properties').newDataInputStream())
+
+
+task wrapper(type: Wrapper) {
+    gradleVersion = '2.10'
+}

flowlayoutmanager/src/main/java/com/xiaofeng/flowlayoutmanager/FlowLayoutManager.java

@@ -3,6 +3,7 @@
 import android.graphics.Point;
 import android.graphics.PointF;
 import android.graphics.Rect;
+import android.os.Build;
 import android.support.annotation.Nullable;
 import android.support.v7.widget.LinearSmoothScroller;
 import android.support.v7.widget.RecyclerView;
@@ -472,17 +473,14 @@ public void onAttachedToWindow(final RecyclerView view) {
 		layoutHelper = new LayoutHelper(this, recyclerView);
 		cacheHelper = new CacheHelper(flowLayoutOptions.itemsPerLine, layoutHelper.visibleAreaWidth());
 		if (layoutHelper.visibleAreaWidth() == 0) {
-			if (globalLayoutListener == null) {
-				globalLayoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
-					@Override
-					public void onGlobalLayout() {
-						view.getViewTreeObserver().removeOnGlobalLayoutListener(this);
-						globalLayoutListener = null;
-						cacheHelper.contentAreaWidth(layoutHelper.visibleAreaWidth());
-					}
-				};
-			}
-			view.getViewTreeObserver().addOnGlobalLayoutListener(globalLayoutListener);
+
+			view.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
+				@Override
+				public void onGlobalLayout() {
+					view.getViewTreeObserver().removeGlobalOnLayoutListener(this);
+					cacheHelper.contentAreaWidth(layoutHelper.visibleAreaWidth());
+				}
+			});
 		}
 
 	}
@@ -491,7 +489,9 @@ public void onGlobalLayout() {
 	public void onDetachedFromWindow(RecyclerView view, RecyclerView.Recycler recycler) {
 		super.onDetachedFromWindow(view, recycler);
 		if (globalLayoutListener != null) {
-			view.getViewTreeObserver().removeOnGlobalLayoutListener(globalLayoutListener);
+			if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
+				view.getViewTreeObserver().removeOnGlobalLayoutListener(globalLayoutListener);
+			}
 			globalLayoutListener = null;
 		}
 	}