#效果演示
#实现 ##自定义控件ImageViewProgressively
public class ImageViewProgressively extends ImageView{ Context mContext; //图片展开或收缩方向，默认为horizontal; private int orientation_progress = 1; //图片展开形式，默认从top到bottom private int expend_type = 0x30; //递增或递减的幅度（level的范围在0-10000），可以为负数 private int level_change_step = 1000; //为了使动画效果明显，设置延迟修改的时间间隔,默认为50ms private int level_change_delayed = 50; public ImageViewProgressively(Context context) { super(context); mContext = context; // TODO Auto-generated constructor stub } public ImageViewProgressively(Context context, AttributeSet attrs) { super(context, attrs); mContext = context; TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.ImageViewProgressively); orientation_progress = array.getInt(R.styleable.ImageViewProgressively_orientation_progress, 1); expend_type = array.getInt(R.styleable.ImageViewProgressively_expend_type, 0x30); level_change_step = array.getInt(R.styleable.ImageViewProgressively_level_change_step, 1000); level_change_delayed = array.getInt(R.styleable.ImageViewProgressively_level_change_delayed, 50); Drawable d = this.getDrawable(); if (d != null) { setImageDrawable(d); } array.recycle(); } @Override public void setImageDrawable(Drawable drawable) { // TODO Auto-generated method stub ClipDrawable mClipDrawable = new ClipDrawable(drawable, expend_type, orientation_progress); super.setImageDrawable(mClipDrawable); if(level_change_step > 0){ mClipDrawable.setLevel(0); }else{ mClipDrawable.setLevel(10000); } this.post(animateImage); } @Override public void setImageBitmap(Bitmap bm) { // TODO Auto-generated method stub setImageDrawable(new BitmapDrawable(mContext.getResources(), bm)); } private Runnable animateImage = new Runnable() { @Override public void run() { doTheAnimation(getDrawable()); } }; private void doTheAnimation(Drawable mDrawable){ mDrawable.setLevel(mDrawable.getLevel() + level_change_step); if (mDrawable.getLevel() <= 10000 && mDrawable.getLevel() >=0) { this.postDelayed(animateImage, level_change_delayed); }else { this.removeCallbacks(animateImage); } }} ##attr定义
##用法
实现效果比较简单，。 这个是以前见到有些网页上出现这种效果，不知道是因为图片数据没下载完整，可以一部分一部分的显示，还是特意做的这种效果，想实现部分图片数据逐步加载显示（一张1m的图片，只下载0.5m的数据，显示图片的一部分），一直还没成功。