Java tutorial
/* * Copyright (C) 2015 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.lamcreations.scaffold.common.views.behaviors; import android.content.Context; import android.os.Build; import android.support.design.widget.CoordinatorLayout; import android.support.design.widget.FloatingActionButton; import android.support.v4.view.ViewCompat; import android.support.v4.view.ViewPropertyAnimatorListener; import android.support.v4.view.animation.FastOutSlowInInterpolator; import android.util.AttributeSet; import android.view.View; import android.view.animation.Animation; import android.view.animation.AnimationUtils; import android.view.animation.Interpolator; import com.lamcreations.scaffold.R; public class FabBehavior extends FloatingActionButton.Behavior { private static final Interpolator INTERPOLATOR = new FastOutSlowInInterpolator(); private boolean mIsAnimatingOut = false; public FabBehavior(Context context, AttributeSet attrs) { super(); } public FabBehavior() { super(); } @Override public boolean onStartNestedScroll(final CoordinatorLayout coordinatorLayout, final FloatingActionButton child, final View directTargetChild, final View target, final int nestedScrollAxes) { return nestedScrollAxes == ViewCompat.SCROLL_AXIS_VERTICAL || super.onStartNestedScroll(coordinatorLayout, child, directTargetChild, target, nestedScrollAxes); } @Override public void onNestedScroll(final CoordinatorLayout coordinatorLayout, final FloatingActionButton child, final View target, final int dxConsumed, final int dyConsumed, final int dxUnconsumed, final int dyUnconsumed) { super.onNestedScroll(coordinatorLayout, child, target, dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed); if (dyConsumed > 0 && !this.mIsAnimatingOut && child.getVisibility() == View.VISIBLE) { animateOut(child); } else if (dyConsumed < 0 && child.getVisibility() != View.VISIBLE) { animateIn(child); } } private void animateOut(final FloatingActionButton button) { if (Build.VERSION.SDK_INT >= 14) { ViewCompat.animate(button).scaleX(0.0F).scaleY(0.0F).alpha(0.0F).setInterpolator(INTERPOLATOR) .withLayer().setListener(new ViewPropertyAnimatorListener() { public void onAnimationStart(View view) { FabBehavior.this.mIsAnimatingOut = true; } public void onAnimationCancel(View view) { FabBehavior.this.mIsAnimatingOut = false; } public void onAnimationEnd(View view) { FabBehavior.this.mIsAnimatingOut = false; view.setVisibility(View.GONE); } }).start(); } else { Animation anim = AnimationUtils.loadAnimation(button.getContext(), R.anim.scaffold_fab_out); anim.setInterpolator(INTERPOLATOR); anim.setDuration(200L); anim.setAnimationListener(new Animation.AnimationListener() { public void onAnimationStart(Animation animation) { FabBehavior.this.mIsAnimatingOut = true; } public void onAnimationEnd(Animation animation) { FabBehavior.this.mIsAnimatingOut = false; button.setVisibility(View.GONE); } @Override public void onAnimationRepeat(final Animation animation) { } }); button.startAnimation(anim); } } private void animateIn(FloatingActionButton button) { button.setVisibility(View.VISIBLE); if (Build.VERSION.SDK_INT >= 14) { ViewCompat.animate(button).scaleX(1.0F).scaleY(1.0F).alpha(1.0F).setInterpolator(INTERPOLATOR) .withLayer().setListener(null).start(); } else { Animation anim = AnimationUtils.loadAnimation(button.getContext(), R.anim.scaffold_fab_in); anim.setDuration(200L); anim.setInterpolator(INTERPOLATOR); button.startAnimation(anim); } } }