前段时间产品那边让我做一个动画，要求是先以横线的方式横向展开，在纵向展示图片，最后展示几秒动画在原路返回,随后我在网上查找资料，发现这方面的记录很少，最后自己写了一个
后期还会慢慢改进；
转载请说明出处：http://www.cnblogs.com/hyylog/p/5659619.html
步骤：1、先利用控件的ondraw()方法，结合数字上升的动画，实现划线的步骤；
2、利用postInvalidate()方法，调用dispatchDraw（）方法来展示图片的展现
具体代码如下：
public class ExpandView extends LinearLayout {
private Bitmap mBitmap;
private int linearDuration = 500; private int expandDuration = 800; private int dismissDuration = 1500; private Paint mpPaint; private Paint bitPaint; private int resultLinear = 40; // 划线动画执行距离完成启动下一个动画的距离 （为防止动画启动延迟产生的卡顿） private int resultBitMap = 30; // 画图动画距离启动下次动画的距离 （为防止动画启动延迟产生的卡顿） private int type = 1; // 1 为展开动画 2 为回缩动画 private ValueAnimator valueAnimator = null; private ValueAnimator valueAnimator2 = null; private int radus = 8; private int velua = 0; private int veluaLinear = 0; private View view; private boolean isStart = false; // 保证动画只启动一次 private Handler handler = new Handler() { public void handleMessage(android.os.Message msg) { switch (msg.what) { case 0: velua = 0; invalidate(); break; case 1: start(2); break; default: break; } }; };public ExpandView(Context context, AttributeSet attrs) {
super(context, attrs); inite(); }public void setView(View view) {
this.view = view; }public ExpandView(Context context) {
super(context); inite(); }public void inite() {
bitPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mpPaint = new Paint(Paint.ANTI_ALIAS_FLAG); mpPaint.setStrokeWidth(5); mpPaint.setColor(Color.BLACK); }public void setRadus(int radus) {
this.radus = radus; }public void setDistance(int linear, int bit) {
resultBitMap = bit; resultLinear = linear; }public void setDuration(int linearDuration, int expandDuration,
int dismissDuration) { this.linearDuration = linearDuration; this.expandDuration = expandDuration; this.dismissDuration = dismissDuration; }public void setLinearPaintColor(int color) {
mpPaint.setColor(color); }public void start(int type) {
this.type = type; valueAnimator.cancel(); valueAnimator2.cancel(); handler.removeMessages(1); handler.sendEmptyMessage(0); isStart = true; if (type == 1) { valueAnimator.start(); } else if (type == 2) { valueAnimator2.start(); } }public void initedAnimation() {
clearAnimations(); mBitmap = getBitmap(); Log.i("", "pppp====veluaLinear=>>"+(mBitmap.getWidth() - radus * 2)); valueAnimator = ValueAnimator.ofInt(0, mBitmap.getWidth() - radus * 2); valueAnimator2 = ValueAnimator.ofInt(0, mBitmap.getHeight()); valueAnimator.setDuration(linearDuration); valueAnimator2.setDuration(expandDuration); valueAnimator.addUpdateListener(new AnimatorUpdateListener() {@Override
public void onAnimationUpdate(ValueAnimator animation) { veluaLinear = (Integer) animation.getAnimatedValue(); if (veluaLinear > (mBitmap.getWidth() - resultLinear)&& type == 1) { if (isStart) { valueAnimator2.start(); isStart = false; } } postInvalidate(); } });valueAnimator2.addUpdateListener(new AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator animation) { velua = (Integer) animation.getAnimatedValue(); postInvalidate(); veluaLinear = 0; } }); }@Override
protected void dispatchDraw(Canvas canvas) { super.dispatchDraw(canvas); if (mBitmap != null) { Rect src; Rect des; if (type == 1) { canvas.drawLine(mBitmap.getWidth() - radus, 0,mBitmap.getWidth() - radus - veluaLinear, 0,mpPaint); src = new Rect(0, 0, mBitmap.getWidth(), velua); des = new Rect(0, 0, mBitmap.getWidth(), velua); } else { canvas.drawLine(mBitmap.getWidth() - radus, 0, radus+ veluaLinear, 0, mpPaint); src = new Rect(0, 0, mBitmap.getWidth(), mBitmap.getHeight()- velua); des = new Rect(0, 0, mBitmap.getWidth(), mBitmap.getHeight()- velua); } canvas.drawBitmap(mBitmap, src, des, bitPaint); if (velua == mBitmap.getHeight() && type == 1) { handler.removeMessages(1); handler.sendEmptyMessageDelayed(1, dismissDuration); } if (type == 2 && velua >= mBitmap.getHeight() - resultBitMap) { if (isStart) { valueAnimator.start(); isStart = false; } } } }public void clearAnimations() {
if (valueAnimator != null) valueAnimator.cancel(); if (valueAnimator2 != null) valueAnimator.cancel(); handler.removeMessages(1); veluaLinear=0; handler.sendEmptyMessage(0); if (mBitmap != null && !mBitmap.isRecycled()) { mBitmap.recycle(); }}
private Bitmap getBitmap() {
// 打开图像缓存 view.setDrawingCacheEnabled(true); // 必须调用measure和layout方法才能成功保存可视组件的截图到png图像文件 // 测量View大小 view.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED)); // 发送位置和尺寸到View及其所有的子View view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight()); Bitmap bitmap = view.getDrawingCache(); android.widget.FrameLayout.LayoutParams params = (android.widget.FrameLayout.LayoutParams) getLayoutParams(); params.width=bitmap.getWidth(); params.height=bitmap.getHeight(); setLayoutParams(params); return bitmap; }}