Android/.svn/pristine/d2/d290a475ecf21537dc446c7a9f9a7656d992467a.svn-base

package eVVM.apk.helper;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.widget.ViewDragHelper;
import android.util.AttributeSet;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.FrameLayout;

import com.nineoldandroids.view.ViewHelper;

public class CommunityView extends FrameLayout {

	// 屏幕宽高
	private int screenHeight;
	private int screenWidth;
	private ViewDragHelper mDragHelper;
	private long lastMultiTouchTime;// 记录多点触控缩放后的时间
	private int originalWidth;// view宽度
	private int originalHeight;// view高度
	private ScaleGestureDetector mScaleGestureDetector = null;
	// private View view;
	private int downX;// 手指按下的x坐标值
	private int downY;// 手指按下的y坐标值
	private int left;// view的左坐标值
	private int top;// view的上坐标值
	private int right;// view的右坐标值
	private int bottom;// view的下坐标值
	private int newHeight;
	private int newWidth;

	private float scale;
	private float preScale = 1;// 默认前一次缩放比例为1

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

	public CommunityView(Context context, AttributeSet attrs) {
		super(context, attrs);
		init(context);
	}

	public CommunityView(Context context) {
		super(context);
		init(context);
	}

	private void init(Context context) {
		mDragHelper = ViewDragHelper.create(this, callback);
		mScaleGestureDetector = new ScaleGestureDetector(context,
				new ScaleGestureListener());

		// view.post(new Runnable() {
		//
		// @Override
		// public void run() {
		// left = view.getLeft();
		// top = view.getTop();
		// right = view.getRight();
		// bottom = view.getBottom();
		// originalWidth = view.getWidth();
		// originalHeight = view.getHeight();
		// }
		// });
	}

	@Override
	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
		super.onSizeChanged(w, h, oldw, oldh);
		screenWidth = getMeasuredWidth();
		screenHeight = getMeasuredHeight();
	}

	@Override
	public boolean onInterceptTouchEvent(MotionEvent ev) {
		super.onInterceptTouchEvent(ev);
		boolean b = mDragHelper.shouldInterceptTouchEvent(ev);// 由mDragHelper决定是否拦截事件，并传递给onTouchEvent
		return b;
	}

	private boolean needToHandle=true;
	@Override
	public boolean onTouchEvent(MotionEvent event) {

		int pointerCount = event.getPointerCount(); // 获得多少点
		if (pointerCount > 1) {// 多点触控，
			switch (event.getAction()) {
				case MotionEvent.ACTION_DOWN:
					needToHandle=false;
					break;
				case MotionEvent.ACTION_MOVE:

					break;
				case MotionEvent.ACTION_POINTER_2_UP://第二个手指抬起的时候
					needToHandle=true;
					break;

				default:
					break;
			}
			return mScaleGestureDetector.onTouchEvent(event);//让mScaleGestureDetector处理触摸事件
		} else {
			long currentTimeMillis = System.currentTimeMillis();
			if (currentTimeMillis - lastMultiTouchTime > 200&&needToHandle) {
//				  多点触控全部手指抬起后要等待200毫秒才能执行单指触控的操作，避免多点触控后出现颤抖的情况
				try {
					mDragHelper.processTouchEvent(event);
				} catch (Exception e) {
					e.printStackTrace();
				}
				return true;
			}
//			}
		}
		return false;
	}

	private ViewDragHelper.Callback callback = new ViewDragHelper.Callback() {
		/**
		 * 用于判断是否捕获当前child的触摸事件
		 *
		 * @param child
		 *            当前触摸的子view
		 * @param pointerId
		 * @return true就捕获并解析；false不捕获
		 */
		@Override
		public boolean tryCaptureView(View child, int pointerId) {
			if (preScale > 1)
				return true;
			return false;
		}

		/**
		 * 控制水平方向上的位置
		 */
		@Override
		public int clampViewPositionHorizontal(View child, int left, int dx) {

			if (left < (screenWidth - screenWidth * preScale) / 2)
				left = (int) (screenWidth - screenWidth * preScale) / 2;// 限制mainView可向左移动到的位置
			if (left > (screenWidth * preScale - screenWidth) / 2)
				left = (int) (screenWidth * preScale - screenWidth) / 2;// 限制mainView可向右移动到的位置
			return left;
		}

		public int clampViewPositionVertical(View child, int top, int dy) {

			if (top < (screenHeight - screenHeight * preScale) / 2) {
				top = (int) (screenHeight - screenHeight * preScale) / 2;// 限制mainView可向上移动到的位置
			}
			if (top > (screenHeight * preScale - screenHeight) / 2) {
				top = (int) (screenHeight * preScale - screenHeight) / 2;// 限制mainView可向上移动到的位置
			}
			return top;
		}

	};

	public class ScaleGestureListener implements
			ScaleGestureDetector.OnScaleGestureListener {

		@Override
		public boolean onScale(ScaleGestureDetector detector) {

			float previousSpan = detector.getPreviousSpan();// 前一次双指间距
			float currentSpan = detector.getCurrentSpan();// 本次双指间距
			if (currentSpan < previousSpan) {
				// 缩小
				// scale = preScale-detector.getScaleFactor()/3;
				scale = preScale - (previousSpan - currentSpan) / 1000;
			} else {
				// 放大
				// scale = preScale+detector.getScaleFactor()/3;
				scale = preScale + (currentSpan - previousSpan) / 1000;
			}
			// 缩放view
			if (scale > 0.5) {
				ViewHelper.setScaleX(CommunityView.this, scale);// x方向上缩放
				ViewHelper.setScaleY(CommunityView.this, scale);// y方向上缩放
			}
			return false;
		}

		@Override
		public boolean onScaleBegin(ScaleGestureDetector detector) {
			// 一定要返回true才会进入onScale()这个函数
			return true;
		}

		@Override
		public void onScaleEnd(ScaleGestureDetector detector) {
			preScale = scale;// 记录本次缩放比例
			lastMultiTouchTime = System.currentTimeMillis();// 记录双指缩放后的时间
		}
	}
}