add: fab and toolbar hide when scrolling

2017-08-21 10:48:11 +08:00
parent 5440788922
commit 602b84fc92
9 changed files with 128 additions and 72 deletions
--- a/app/src/main/java/com/stardust/widget/ScrollAwareFABBehavior.java
+++ b/app/src/main/java/com/stardust/widget/ScrollAwareFABBehavior.java
@@ -0,0 +1,84 @@
+package com.stardust.widget;
+
+import android.animation.Animator;
+import android.animation.AnimatorListenerAdapter;
+import android.animation.TimeInterpolator;
+import android.content.Context;
+import android.support.design.widget.CoordinatorLayout;
+import android.support.design.widget.FloatingActionButton;
+import android.support.v4.view.animation.FastOutSlowInInterpolator;
+import android.util.AttributeSet;
+import android.view.View;
+
+/**
+ * Created by Stardust on 2017/8/20.
+ */
+
+public class ScrollAwareFABBehavior extends FloatingActionButton.Behavior {
+
+    private static final long DURATION = 200;
+    private static final TimeInterpolator INTERPOLATOR = new FastOutSlowInInterpolator();
+    private boolean mHidden = false;
+
+    public ScrollAwareFABBehavior(Context context, AttributeSet attrs) {
+        super();
+    }
+
+    @Override
+    public boolean onStartNestedScroll(CoordinatorLayout coordinatorLayout, FloatingActionButton child, View directTargetChild, View target, int nestedScrollAxes) {
+        return true;
+    }
+
+    @Override
+    public void onNestedScroll(CoordinatorLayout coordinatorLayout, FloatingActionButton child, View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed) {
+        super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed);
+        if (dyConsumed > 0) {
+            onScrollDown(coordinatorLayout, child);
+        } else if (dyConsumed < 0) {
+            onScrollUp(coordinatorLayout, child);
+        }
+    }
+
+    private void onScrollUp(CoordinatorLayout parent, FloatingActionButton button) {
+        if (!mHidden) {
+            return;
+        }
+        startShowingAnimation(parent, button);
+    }
+
+    private void startShowingAnimation(CoordinatorLayout parent, FloatingActionButton button) {
+        button.animate()
+                .translationY(0)
+                .setDuration(DURATION)
+                .setListener(new AnimatorListenerAdapter() {
+                    @Override
+                    public void onAnimationEnd(Animator animation) {
+                        mHidden = false;
+                    }
+                })
+                .start();
+    }
+
+    private void onScrollDown(CoordinatorLayout parent, FloatingActionButton button) {
+        if (mHidden) {
+            return;
+        }
+        startHidingAnimation(parent, button);
+    }
+
+    private void startHidingAnimation(CoordinatorLayout parent, FloatingActionButton button) {
+        button.animate()
+                .translationY(parent.getY() + parent.getHeight() - button.getY())
+                .setDuration(DURATION)
+                .setInterpolator(INTERPOLATOR)
+                .setListener(new AnimatorListenerAdapter() {
+                    @Override
+                    public void onAnimationEnd(Animator animation) {
+                        mHidden = true;
+                    }
+                })
+                .start();
+    }
+
+
+}