package com.sky_dreaming.ACDsee.gallery_view;
import android.content.Context;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.Transformation;
import android.widget.Gallery;
import android.widget.ImageView;
/**
* ****************************************************************
* 文件名称 : GalleryFlow.java
* 创建时间 : 2010-11-2 下午05:27:46
* 文件描述 : 自定义Gallery视图,实现图片旋转效果
*****************************************************************
*/
public class GalleryFlow extends Gallery {
/**
* 用于ImageView的矩阵变换
*/
private Camera mCamera = new Camera();
private int mMaxRotationAngle = 60;
/**
* The maximum zoom on the centre Child
*/
private int mMaxZoom = -120;
/**
* Coverflow的中心
*/
private int mCoveflowCenter;
public GalleryFlow(Context context) {
super(context);
this.setStaticTransformationsEnabled(true);
}
public GalleryFlow(Context context, AttributeSet attrs) {
super(context, attrs);
this.setStaticTransformationsEnabled(true);
}
public GalleryFlow(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
this.setStaticTransformationsEnabled(true);
}
/**
* get set 方法
* @return
*/
public int getMaxRotationAngle() {
return mMaxRotationAngle;
}
public void setMaxRotationAngle(int maxRotationAngle) {
mMaxRotationAngle = maxRotationAngle;
}
public int getMaxZoom() {
return mMaxZoom;
}
public void setMaxZoom(int maxZoom) {
mMaxZoom = maxZoom;
}
/**
* 获取Coverflow的中心位置
* @return
*/
private int getCenterOfCoverflow() {
return (getWidth() - getPaddingLeft() - getPaddingRight()) / 2
+ getPaddingLeft();
}
/**
* 获取子视图的中心位置
* @param view
* @return
*/
private static int getCenterOfView(View view) {
return view.getLeft() + view.getWidth() / 2;
}
protected boolean getChildStaticTransformation(View child, Transformation t) {
final int childCenter = getCenterOfView(child);
final int childWidth = child.getWidth();
int rotationAngle = 0;
/**
* 重置transformation
*/
t.clear();
t.setTransformationType(Transformation.TYPE_MATRIX);
if (childCenter == mCoveflowCenter) {
transformImageBitmap((ImageView) child, t, 0);
} else {
/**
* 计算旋转角度
*/
rotationAngle = (int) (((float) (mCoveflowCenter - childCenter) / childWidth) * mMaxRotationAngle);
if (Math.abs(rotationAngle) > mMaxRotationAngle) {
rotationAngle = (rotationAngle < 0) ? -mMaxRotationAngle: mMaxRotationAngle;
}
transformImageBitmap((ImageView) child, t, rotationAngle);
}
return true;
}
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
mCoveflowCenter = getCenterOfCoverflow();
super.onSizeChanged(w, h, oldw, oldh);
}
/**
* 将子视图旋转相应角度 ?????????????
*
* @param imageView
* ImageView the ImageView whose bitmap we want to rotate
* @param t
* transformation
* @param rotationAngle
* the Angle by which to rotate the Bitmap
*/
private void transformImageBitmap(ImageView child, Transformation t,
int rotationAngle) {
/**
* 保存相机当前状态
*/
mCamera.save();
/**
* 获取变换矩阵
*/
final Matrix imageMatrix = t.getMatrix();
final int imageHeight = child.getLayoutParams().height;
final int imageWidth = child.getLayoutParams().width;
final int rotation = Math.abs(rotationAngle);
/**
* 在Z轴上正向移动camera的视角,实际效果为放大图片。
* 如果在Y轴上移动,则图片上下移动;X轴上对应图片左右移动。
*/
mCamera.translate(0.0f, 0.0f, 100.0f);
// As the angle of the view gets less, zoom in
if (rotation < mMaxRotationAngle) {
float zoomAmount = (float) (mMaxZoom + (rotation * 1.5));
mCamera.translate(0.0f, 0.0f, zoomAmount);
}
/**
* 在Y轴上旋转,对应图片竖向向里翻转。如果在X轴上旋转,则对应图片横向向里翻转。
*/
mCamera.rotateY(rotationAngle);
mCamera.getMatrix(imageMatrix);
imageMatrix.preTranslate(-(imageWidth / 2), -(imageHeight / 2));
imageMatrix.postTranslate((imageWidth / 2), (imageHeight / 2));
/**
* 恢复相机原状态
*/
mCamera.restore();
}
}