ContentLoadingProgressBar 对从 Lottie 获取的自定义动画的行为

Question

您知道我们需要 ContentLoadingProgressBar 的原因。我的动画从 Lottie 加载为 json。它工作得很好。

我的问题是我希望我的 Lottie 导入动画的行为与 ContentLoadingProgressBar 相同。那就是在隐藏它之前至少显示 X 秒，而不是立即隐藏它。

我怎样才能做到这一点？任何建议都会非常适用。

我知道我可以通过 Runnable 或其他方式实现类似的行为。但是我需要一个优化的解决方案，这样我就不必在 showing/hiding 进度条时每次都编写样板代码。

Answer 1

您可以从 LottieAnimationView 扩展 ContentLoadingLottieAnimationView 并且实现类似于 ContentLoadingProgressBar:

/*
 * Copyright (C) 2013 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.
 */

import android.content.Context;
import android.util.AttributeSet;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

import com.airbnb.lottie.LottieAnimationView;

public class ContentLoadingLottieAnimationView extends LottieAnimationView {

    private static final int MIN_SHOW_TIME = 500; // ms
    private static final int MIN_DELAY = 500; // ms

    long mStartTime = -1;

    boolean mPostedHide = false;

    boolean mPostedShow = false;

    boolean mDismissed = false;

    private final Runnable mDelayedHide = new Runnable() {

        @Override
        public void run() {
            mPostedHide = false;
            mStartTime = -1;
            pauseAnimation();
        }
    };

    private final Runnable mDelayedShow = new Runnable() {

        @Override
        public void run() {
            mPostedShow = false;
            if (!mDismissed) {
                mStartTime = System.currentTimeMillis();
                playAnimation();
            }
        }
    };

    public ContentLoadingLottieAnimationView(@NonNull Context context) {
        this(context, null);
    }

    public ContentLoadingLottieAnimationView(@NonNull Context context, @Nullable AttributeSet attrs) {
        super(context, attrs, 0);
    }

    @Override
    public void onAttachedToWindow() {
        super.onAttachedToWindow();
        removeCallbacks();
    }

    @Override
    public void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        removeCallbacks();
    }

    private void removeCallbacks() {
        removeCallbacks(mDelayedHide);
        removeCallbacks(mDelayedShow);
    }

    /**
     * Hide the progress view if it is visible. The progress view will not be
     * hidden until it has been shown for at least a minimum show time. If the
     * progress view was not yet visible, cancels showing the progress view.
     */
    public synchronized void hide() {
        mDismissed = true;
        removeCallbacks(mDelayedShow);
        mPostedShow = false;
        long diff = System.currentTimeMillis() - mStartTime;
        if (diff >= MIN_SHOW_TIME || mStartTime == -1) {
            // The progress spinner has been shown long enough
            // OR was not shown yet. If it wasn't shown yet,
            // it will just never be shown.
            pauseAnimation();
        } else {
            // The progress spinner is shown, but not long enough,
            // so put a delayed message in to hide it when its been
            // shown long enough.
            if (!mPostedHide) {
                postDelayed(mDelayedHide, MIN_SHOW_TIME - diff);
                mPostedHide = true;
            }
        }
    }

    /**
     * Show the progress view after waiting for a minimum delay. If
     * during that time, hide() is called, the view is never made visible.
     */
    public synchronized void show() {
        // Reset the start time.
        mStartTime = -1;
        mDismissed = false;
        removeCallbacks(mDelayedHide);
        mPostedHide = false;
        if (!mPostedShow) {
            postDelayed(mDelayedShow, MIN_DELAY);
            mPostedShow = true;
        }
    }
}

用法与原始用法类似 ContentLoadingProgressBar。

ContentLoadingProgressBar 对从 Lottie 获取的自定义动画的行为

ContentLoadingProgressBar behviour on custom animation acquired from Lottie

android

android-progressbar

lottie