1 /* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.email.activity; 18 19 import android.animation.Animator; 20 import android.animation.ObjectAnimator; 21 import android.animation.PropertyValuesHolder; 22 import android.animation.TimeInterpolator; 23 import android.content.Context; 24 import android.view.ViewGroup; 25 import android.view.animation.DecelerateInterpolator; 26 import android.widget.TextView; 27 28 /** 29 * Class to hide/show a banner. 30 */ 31 public class BannerController { 32 private static final int ANIMATION_DURATION = 100; 33 private static final TimeInterpolator INTERPOLATOR = new DecelerateInterpolator(1.5f); 34 35 private final TextView mBannerView; 36 private final int mBannerHeight; 37 38 private boolean mShown; 39 40 /** Hold last animator to cancel. */ 41 private Animator mLastAnimator; 42 BannerController(Context context, TextView bannerView, int bannerHeight)43 public BannerController(Context context, TextView bannerView, int bannerHeight) { 44 mBannerView = bannerView; 45 mBannerHeight = bannerHeight; 46 47 setBannerYAnim(-mBannerHeight); // hide by default. 48 } 49 50 /** 51 * @return the current y position of the banner. 52 */ getBannerY()53 private int getBannerY() { 54 return ((ViewGroup.MarginLayoutParams) mBannerView.getLayoutParams()).topMargin; 55 } 56 57 private static final String PROP_SET_BANNER_Y = "bannerYAnim"; 58 59 /** 60 * Set the Y position of the banner. public, but should only be used by animators. 61 */ setBannerYAnim(int y)62 public void setBannerYAnim(int y) { 63 ((ViewGroup.MarginLayoutParams) mBannerView.getLayoutParams()).topMargin = y; 64 mBannerView.requestLayout(); 65 } 66 67 /** 68 * Show a banner with a message. 69 * 70 * @return false if a banner is already shown, in which case the message won't be updated. 71 */ show(String message)72 public boolean show(String message) { 73 if (mShown) { 74 return false; // If already shown, don't change the message, to avoid flicker. 75 } 76 mShown = true; 77 mBannerView.setText(message); 78 slideBanner(0); 79 return true; 80 } 81 82 /** 83 * Dismiss a banner. 84 */ dismiss()85 public void dismiss() { 86 if (!mShown) { 87 return; // Always hidden, or hiding. 88 } 89 mShown = false; 90 slideBanner(-mBannerHeight); // Slide up to hide. 91 } 92 slideBanner(int toY)93 private void slideBanner(int toY) { 94 if (mLastAnimator != null) { 95 mLastAnimator.cancel(); 96 } 97 98 final PropertyValuesHolder[] values = { 99 PropertyValuesHolder.ofInt(PROP_SET_BANNER_Y, getBannerY(), toY) }; 100 final ObjectAnimator animator = ObjectAnimator.ofPropertyValuesHolder( 101 this, values).setDuration(ANIMATION_DURATION); 102 animator.setInterpolator(INTERPOLATOR); 103 mLastAnimator = animator; 104 animator.start(); 105 } 106 } 107