通过使用Timer（或Handler）更改ImageView中的图像来创建动画 [英] Create animation by changing image in ImageView with Timer (or Handler)

问题描述

我想通过更改ImageView内部的帧来创建简单的动画。我不想使用AnimationDrawable，因为我需要在帧更改或动画停止时接收事件，以便能够向后播放，重新启动等等。

I want to create an simple animation by changing frames inside an ImageView. I don't want to use AnimationDrawable because i need to receive events when a frame changed or when the animation stoped, to be able to play it backwards, restart it and so on.

我的问题是，尽管setImageDrawable被调用了（在主线程上），框架实际上并没有改变事件。因此，除了框架没有变化（实际上只是绘制了一个框架，第一个框架）外，其他所有东西似乎都正常运行。

My problem is that the frames doesn't actually change event though setImageDrawable gets called (on the main thread). So everythings seems to work fine excepts that the frames doesn't change (actually just a frame is drawn, the first one).

所以我的代码：

public class AnimatedImageView extends ImageView implements Animatable, Runnable {

    private static final String TAG = "AnimatedImageView";

    public static interface AnimationEventsListener {
        void animationDidChangeFrame(AnimatedImageView animatedImageView);

        void animationDidStop(AnimatedImageView animatedImageView);
    }

    /* frames - ress ids */
    private int[] mFrameResIds;
    /* current frame index */
    private int mCurrentFrameIdx;
    /* number of the current repeat */
    private int loopIndex;
    /* number of animation repetiotions, 0 for infinite */
    private int mNumOfRepetitions;
    /* if animation is playing */
    private boolean playing;
    /* if animation is paused */
    private boolean paused;
    /* if animation is playing backward */
    private boolean playItBackward;
    /* animation duration */
    private long mAnimationDuration;
    /* frame animation duration (mAnimationDuration / num_of_frames) */
    private long mFrameAnimationDuration;

    /* listener for animation events */
    private AnimationEventsListener mListener;

    private Handler mHandler;

    public AnimatedImageView(Context context) {
        super(context);
        setup();
    }

    public AnimatedImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        setup();
    }

    public AnimatedImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        setup();
    }

    private void setup() {
        mHandler = new Handler(Looper.getMainLooper());
        this.setClickable(true);
        Logger.d("MSG", "setup, thread: " + Thread.currentThread().toString());
    }


    @Override
    public void start() {
        if (playing) {
            return;
        }
        mCurrentFrameIdx = playItBackward ? mFrameResIds.length - 1 : 0;
        loopIndex = 0;
        playing = true;
        updateFrame();
    }

    @Override
    public void stop() {
        paused = true;
    }

    public void resume() {
        paused = false;
        playing = true;
        updateFrame();
    }

    @Override
    public boolean isRunning() {
        return false;
    }

    @Override
    public void run() {
        Logger.d("MSG", "run, thread: " + Thread.currentThread().toString());
        updateFrame();
    }

    public AnimationEventsListener getListener() {
        return mListener;
    }

    public void setListener(AnimationEventsListener mListener) {
        this.mListener = mListener;
    }

    public long getAnimationDuration() {
        return mAnimationDuration;
    }

    public void setAnimationDuration(long mAnimationDuration) {
        this.mAnimationDuration = mAnimationDuration;
        if (mFrameResIds != null) {
            mFrameAnimationDuration = mAnimationDuration / mFrameResIds.length;
        }
    }

    public int[] getFrameResIds() {
        return mFrameResIds;
    }

    public void setFrameResIds(int[] mFrameResIds) {
        this.mFrameResIds = mFrameResIds;
        if (mFrameResIds != null) {
            mFrameAnimationDuration = mAnimationDuration / mFrameResIds.length;
        }
    }

    private void setCurrentFrame(int frameValue) {
        mCurrentFrameIdx = frameValue;
        this.setAnimationFrame(frameValue);
    }

    private void setAnimationFrame(int animationFrame) {
        Logger.d("MSG", "setAnimationFrame: " + animationFrame);
        if (animationFrame < 0) {
            animationFrame = 0;
        }

        if (animationFrame > -1) {
            animationFrame = mFrameResIds.length - 1;
        }

        Resources resources = getResources();
        AnimatedImageView.this.setImageDrawable(resources.getDrawable(mFrameResIds[animationFrame]));
        AnimatedImageView.this.forceLayout();
//        AnimatedImageView.this.setImageBitmap(BitmapFactory.decodeResource(resources, mFrameResIds[animationFrame]));
//        this.setImageResource(mFrameResIds[animationFrame]);
        AnimatedImageView.this.invalidate();
    }

    private void updateFrame() {
        Logger.d("MSG", "updateFrame " + mCurrentFrameIdx);
        if (!playing || paused) {
            return;
        }

        playing = false;

        if (mListener != null) {
            mListener.animationDidChangeFrame(AnimatedImageView.this);
        }

        if (!playItBackward) {
            mCurrentFrameIdx++;
            if (mCurrentFrameIdx >= mFrameResIds.length) {
                loopIndex++;
                mCurrentFrameIdx = 0;
                if (mNumOfRepetitions == loopIndex) {
                    if (mListener != null) {
                        mListener.animationDidStop(AnimatedImageView.this);
                    }
                    return;
                }
            }
        } else {
            mCurrentFrameIdx--;
            if (mCurrentFrameIdx < 0) {
                loopIndex++;
                mCurrentFrameIdx = mFrameResIds.length - 1;
                if (mNumOfRepetitions == loopIndex) {
                    if (mListener != null) {
                        mListener.animationDidStop(AnimatedImageView.this);
                    }
                    return;
                }
            }
        }

        playing = true;

        setAnimationFrame(mCurrentFrameIdx);
//        mHandler.postDelayed(AnimatedImageView.this, mFrameAnimationDuration);
//        scheduleDrawable(getResources().getDrawable(mFrameResIds[mCurrentFrameIdx]), AnimatedImageView.this, mFrameAnimationDuration);
//        postDelayed()
        postDelayed(AnimatedImageView.this, mFrameAnimationDuration);

//        SongPlayerActivity.handler.postDelayed(AnimatedImageView.this, mFrameAnimationDuration);
    }

我在xml的布局中有一个AnimatedImageView对象，在我的活动中，我发现

I have an AnimatedImageView object in my layout in xml and in my activity i find it by id and start the animation on click:

final AnimatedImageView mDriverAnimation = (AnimatedImageView) findViewById(R.id.driver);
        mDriverAnimation.setFrameResIds(new int[]{R.drawable.song1_driver1, R.drawable.song1_driver2, R.drawable.song1_driver3});
        mDriverAnimation.setAnimationDuration(3 * 1000);
        mDriverAnimation.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View view) {
                mDriverAnimation.start();
            }
        });

有什么想法吗？ :)谢谢。

Any ideas? :) Thanks.

推荐答案

我认为TransitionDrawable可以解决您的问题： http://developer.android.com/reference/android/graphics/drawable/TransitionDrawable.html

I think that TransitionDrawable could solve your problem: http://developer.android.com/reference/android/graphics/drawable/TransitionDrawable.html

Drawable[] layers = new Drawable[2];
layers[0] = //your first drawable
layers[1] = //your second drawable
TransitionDrawable transition = new TransitionDrawable(layers);
myImageView.setImageDrawable(transition);
transition.startTransition(1500);

这篇关于通过使用Timer（或Handler）更改ImageView中的图像来创建动画的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！