Android UI控件之Gallery --拖动、覆盖、循环、3D图片浏览 效果之二

                 上一篇博客中实现了一种3d效果的图片浏览功能，但是感觉上还是太过"硬性"，因此对上

        一次做一些改进。好了话不多说直接给出效果图吧。小编是“刀剑”的粉丝，因此就以“刀剑”为

        背景吧！

                     第一张：

                拖动到第二张

              拖动时的过渡效果

                实现方式就是重新继承Gallery

               具体如下：

package com.android.CustomGallery;

import android.content.Context;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.view.animation.Transformation;
import android.widget.Gallery;
import android.widget.ImageView;

public class GalleryFlow extends Gallery {

	/**
	 * Graphics Camera used for transforming the matrix of ImageViews
	 */
	private Camera mCamera = new Camera();

	/**
	 * The maximum angle the Child ImageView will be rotated by
	 */
	private int mMaxRotationAngle = 50;

	/**
	 * The maximum zoom on the centre Child
	 */
	private int mMaxZoom = -250;

	/**
	 * The Centre of the Coverflow
	 */
	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 the max rotational angle of the image
	 * 
	 * @return the mMaxRotationAngle
	 */
	public int getMaxRotationAngle() {
		return mMaxRotationAngle;
	}

	/**
	 * Set the max rotational angle of each image
	 * 
	 * @param maxRotationAngle
	 *            the mMaxRotationAngle to set
	 */
	public void setMaxRotationAngle(int maxRotationAngle) {
		mMaxRotationAngle = maxRotationAngle;
	}

	/**
	 * Get the Max zoom of the centre image
	 * 
	 * @return the mMaxZoom
	 */
	public int getMaxZoom() {
		return mMaxZoom;
	}

	/**
	 * Set the max zoom of the centre image
	 * 
	 * @param maxZoom
	 *            the mMaxZoom to set
	 */
	public void setMaxZoom(int maxZoom) {
		mMaxZoom = maxZoom;
	}

	/**
	 * Get the Centre of the Coverflow
	 * 
	 * @return The centre of this Coverflow.
	 */
	private int getCenterOfCoverflow() {
		//Log.e("CoverFlow Width+Height", getWidth() + "*" + getHeight());
		return (getWidth() - getPaddingLeft() - getPaddingRight()) / 2
				+ getPaddingLeft();
	}

	/**
	 * Get the Centre of the View
	 * 
	 * @return The centre of the given view.
	 */
	private static int getCenterOfView(View view) {
		/*Log.e("ChildView Width+Height", view.getWidth() + "*"
				+ view.getHeight());*/
		return view.getLeft() + view.getWidth() / 2;
	}

	/**
	 * {@inheritDoc}
	 * 
	 * @see #setStaticTransformationsEnabled(boolean)
	 */
	protected boolean getChildStaticTransformation(View child, Transformation t) {

		final int childCenter = getCenterOfView(child);
		final int childWidth = child.getWidth();
		int rotationAngle = 0;

		t.clear();
		t.setTransformationType(Transformation.TYPE_MATRIX);

		if (childCenter == mCoveflowCenter) {
			transformImageBitmap((ImageView) child, t, 0);
		} else {
			rotationAngle = (int) (((float) (mCoveflowCenter - childCenter) / childWidth) * mMaxRotationAngle);
			if (Math.abs(rotationAngle) > mMaxRotationAngle) {
				rotationAngle = (rotationAngle < 0) ? -mMaxRotationAngle: mMaxRotationAngle;
			}
			transformImageBitmap((ImageView) child, t, rotationAngle);
		}

		return true;
	}

	/**
	 * This is called during layout when the size of this view has changed. If
	 * you were just added to the view hierarchy, you're called with the old
	 * values of 0.
	 * 
	 * @param w
	 *            Current width of this view.
	 * @param h
	 *            Current height of this view.
	 * @param oldw
	 *            Old width of this view.
	 * @param oldh
	 *            Old height of this view.
	 */
	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
		mCoveflowCenter = getCenterOfCoverflow();
		super.onSizeChanged(w, h, oldw, oldh);
	}

	private void transformImageBitmap(ImageView child, Transformation t,
			int rotationAngle) {
		mCamera.save();
		final Matrix imageMatrix = t.getMatrix();
		final int imageHeight = child.getLayoutParams().height;
		final int imageWidth = child.getLayoutParams().width;
		final int rotation = Math.abs(rotationAngle);

		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);
			((ImageView) (child)).setAlpha((int) (255 - rotation * 2.5));
		}

		
		mCamera.rotateY(rotationAngle);
		mCamera.getMatrix(imageMatrix);
		imageMatrix.preTranslate(-(imageWidth / 2), -(imageHeight / 2));
		imageMatrix.postTranslate((imageWidth / 2), (imageHeight / 2));
		mCamera.restore();
	}
}

                至于布局文件，与上篇并无多大差别！这里就不给出了

                    完整源码部分：