android动画如何显示一张图片从左到右展示出来

Question

不是位移动画,想要那种从一条边隐藏的,慢慢的展示出来完整的图片,类似从一条边拉伸出来,请大神贴上完整代码谢谢

Answer 1

代码:
package com.my.ui;

import android.animation.ObjectAnimator;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.AccelerateDecelerateInterpolator;

/**

Created by my
*/
public class RenderingView extends View implements View.OnClickListener{
//是否layout完成
private boolean mInit;

private Paint mPaint;

private RectF mRectF;

// 0 - 1
private float mProgress;

private Bitmap mCurBitmap;
private Rect mBitmapRect;
private RectF mDrawableRectF;

private Rect mSrc;
private RectF mDst;

private static final int DEFAULT_ANIMATION_DURATION = 1000;

private OnClickListener mClickListener;

private ObjectAnimator mAnimator;

public RenderingView(Context context) {
this(context, null);
}

public RenderingView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}

public RenderingView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}

private void init(){
mInit = false;
mPaint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);
mRectF = new RectF();
mBitmapRect = new Rect();
mDrawableRectF = new RectF();
mSrc = new Rect();
mDst = new RectF();
mProgress = 0;
mAnimator = ObjectAnimator.ofFloat(this, "progress", 1);
mAnimator.setInterpolator(new AccelerateDecelerateInterpolator());
super.setOnClickListener(this);
}

@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
if(changed){
doInit(getViewRect(this));
}
}

/**

获取某个View的正确的位置
@param view
@return */ public static RectF getViewRect(View view){ int vLeft, vTop; int location[] = new int[2]; view.getLocationInWindow(location); vLeft = location[0]; vTop = location[1]; RectF mViewRect = new RectF(vLeft, vTop, vLeft + view.getWidth(), vTop + view.getHeight()); return mViewRect; }
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if(mInit && mCurBitmap != null){
mSrc.set(mBitmapRect.left, mBitmapRect.top, (int)(mBitmapRect.right * mProgress + 0.5f), mBitmapRect.bottom);
mDst.set(mDrawableRectF.left, mDrawableRectF.top, mDrawableRectF.right * mProgress, mDrawableRectF.bottom);
canvas.drawBitmap(mCurBitmap, mSrc, mDst, mPaint);
}
}

private void doInit(RectF rectF){
if(!mInit || !mRectF.equals(rectF)){
mRectF.set(rectF);
if(mCurBitmap != null){
setInformation();
}
mInit = true;
}
}

public float getProgress() {
return mProgress;
}

public void setProgress(float progress) {
this.mProgress = progress;
invalidate();
}

public void setImageBitmap(Bitmap bitmap){
mCurBitmap = bitmap;
if (mCurBitmap != null && mInit) {
setInformation();
}
}

/**

设置一些信息
图片显示默认是fitCenter样式的 */ public void setInformation(){ float w = mCurBitmap.getWidth(); float h = mCurBitmap.getHeight(); float viewW = mRectF.width(); float viewH = mRectF.height(); mBitmapRect.set(0, 0, (int)w, (int)h); if(w / h > viewW / viewH){//顶着宽 float curH = h * viewW / w; mDrawableRectF.set(0, (viewH - curH) / 2, viewW, (viewH - curH) / 2 + curH); } else{//顶高 float curW = w * viewH / h; mDrawableRectF.set((viewW - curW) / 2, 0, (viewW - curW) / 2 + curW, viewH); } beginAnimation(DEFAULT_ANIMATION_DURATION); }
public void beginAnimation(int duration){
setProgress(0);
mAnimator.cancel();
mAnimator.setDuration(duration).start();
}

@Override
public void setOnClickListener(OnClickListener l) {
mClickListener = l;
}

@Override
public void onClick(View v) {
beginAnimation(DEFAULT_ANIMATION_DURATION);
if(mClickListener != null){
mClickListener.onClick(v);
}
}
}

用法:
写在XML中然后,
RenderingView renderingView = (RenderingView)findViewById(R.id.renderview);
renderingView.setImageBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.test));