android自定义控件-瀑布流

业务需要，需要写一个支持自动换行的容器。

之前同事写的感觉可定制化程度太低，于是自己写了一个。。

支持的效果如下图

备注：所有容器添加的都是一样的views，只是设置的参数不一样。

代码如下：

package com.xt.androidproject.mywidget;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.widget.LinearLayout;

import com.xt.androidproject.util.DeviceInfoUtil;

/**
 * Created by lxl on 2015/12/15;
 * Update by lxl on 2016/04/29.
 */
public class HotelTagsView extends ViewGroup {

	// 默认间距
	/**
	 * 水平方向间隔
	 */
	private int mHorizontalSpacing = DeviceInfoUtil.getPixelFromDip(
			this.getContext(), 3);
	/**
	 * 竖直方向间隔
	 */
	private int mVerticalSpacing = DeviceInfoUtil.getPixelFromDip(
			this.getContext(), 5);

	/**
	 * 记录要展示的view
	 */
	private List> mViews = new ArrayList>();

	// 基础属性-最大宽度
	private int mMaxWidth = 0;

	/**
	 * 最后一个view是控制不显示(true)，还是显示一部分(false)
	 */
	private boolean mIsNeedGrep = true;

	/**
	 * 是否可换行 不可换行其实就是把最大行数设置为1
	 */
	private boolean mIsCanMulti = false;

	/**
	 * 必定显示的view，当一行显示不下时，该view在第二行展示. mCanWrap属性设置为true的时候，该属性无效
	 */
	private View mMainView;

	/**
	 * 最大行数
	 */
	private int mMaxLine = 3;//

	/**
	 * 是否自适应宽度
	 */
	private boolean mWarpWidth = false;//

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

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		super.onMeasure(widthMeasureSpec, heightMeasureSpec);
		mViews.clear();

		int maxShowWidth = mMaxWidth;
		if (maxShowWidth <= 0) {
			maxShowWidth = MeasureSpec.getSize(widthMeasureSpec);
		}
		// int maxShowHeight =
		// MeasureSpec.getSize(heightMeasureSpec);//高度还是不要设置了

		/** current line */
		int N = this.getChildCount();
		if (N == 0) {
			return;
		}

		int maxWidth = 0;
		int maxHeight = 0;

		/** each padding value */
		int paddingTop = this.getPaddingTop();
		int paddingBottom = this.getPaddingBottom();
		int paddingLeft = this.getPaddingLeft();
		int paddingRight = this.getPaddingRight();

		int[] params;
		if (mMainView == null) {
			params = measureMultiLine(N, maxShowWidth, paddingLeft,
					paddingRight);
			maxWidth += (paddingRight + paddingLeft);
			maxHeight += (paddingTop + paddingBottom);
		} else {
			params = measureHaveMainViewLine(N, maxShowWidth, paddingLeft,
					paddingRight);
			maxWidth += (paddingRight + paddingLeft);
			maxHeight += (paddingTop + paddingBottom);
		}
		// 设置view宽和高
		maxWidth = mWarpWidth ? params[0] : maxShowWidth;
		maxHeight = params[1];
		setMeasuredDimension(maxWidth, maxHeight);
	}

	/**
	 * 指定了mMainView，会返回两行
	 */
	private int[] measureHaveMainViewLine(int N, int maxShowWidth,
			int paddingLeft, int paddingRight) {

		ArrayList line0 = new ArrayList();
		mViews.add(line0);

		List prepareViews = new ArrayList();
		HashMap whMap = new HashMap();
		int aWidth = 0;
		int pWidth = 0;
		int maxWidth = 0;
		int maxHeight = 0;
		int horizontalWidth = 0;

		// 遍历分类普通和预存views
		for (int i = 0; i < N; i++) {
			View childView = this.getChildAt(i);
			measureChildView(childView);
			int measuredWidth = childView.getMeasuredWidth();
			int measuredHeight = childView.getMeasuredHeight();
			if (i > 0) {
				horizontalWidth = mHorizontalSpacing;
			}
			if (childView == mMainView || prepareViews.size() > 0) {
				prepareViews.add(childView);
				pWidth += (measuredWidth + horizontalWidth);
			} else {
				line0.add(childView);
				aWidth += (measuredWidth + horizontalWidth);
			}
			int[] wh = new int[2];
			wh[0] = measuredWidth;
			wh[1] = measuredHeight;
			whMap.put(childView, wh);
		}

		if ((paddingLeft + paddingRight + aWidth + pWidth) <= maxShowWidth) {
			// 可以完全展示，一行展示
			line0.addAll(prepareViews);
		} else if (prepareViews.size() > 0) {
			// 不能完全展示，mainView二行展示
			View remove = prepareViews.remove(0);
			int[] removewh = whMap.get(remove);
			maxHeight += remove.getMeasuredHeight() + mVerticalSpacing;
			maxWidth = remove.getMeasuredWidth();
			maxWidth = removewh[0];

			ArrayList line1 = new ArrayList();
			line1.add(remove);
			mViews.add(line1);

			for (View view : prepareViews) {
				int[] wh = whMap.get(view);
				if ((aWidth + wh[0]) <= maxShowWidth) {
					// 判断是否为第一个
					aWidth += (wh[0] + (line0.size() > 0 ? horizontalWidth : 0));
					line0.add(view);
				} else {
					// 根据标记位判断是否添加最后一个
					if (!mIsNeedGrep) {
						line0.add(view);
					}
					break;
				}
			}
		}

		/** 宽度为第一行的宽度 */
		int realWidth = 0;
		int realHeight = 0;
		if (line0.size() > 0) {
			int INDEX = line0.size() - 1;
			for (int index = 0; index <= INDEX; index++) {
				realWidth += line0.get(index).getMeasuredWidth()
						+ mHorizontalSpacing;
				realHeight = Math.max(realHeight, line0.get(index)
						.getMeasuredHeight());
			}
		}
		maxHeight += realHeight;
		maxWidth = Math.max(maxWidth, realWidth);

		return new int[] { maxWidth, maxHeight };
	}

	private int[] measureMultiLine(int N, int maxShowWidth, int paddingLeft,
			int paddingRight) {
		int[] maxParams = new int[2];

		int currentLine = 0;
		int lineWidth = 0;
		int lineHeight = 0;
		int verticalHeight = 0;
		int horizontalWidth = 0;
		boolean isFirst = true;

		for (int i = 0; i < N; i++) {
			View childView = this.getChildAt(i);
			measureChildView(childView);
			int measuredWidth = childView.getMeasuredWidth();
			int measuredHeight = childView.getMeasuredHeight();

			// 判断是否需要新建一行
			ArrayList arrayList;

			if ((maxShowWidth - lineWidth - paddingRight - paddingLeft) >= measuredWidth
					+ horizontalWidth) {

				lineHeight = Math.max(lineHeight, measuredHeight);
				lineWidth += (measuredWidth + horizontalWidth);
				// 每行的第一个宽度间距为0，第二个起计算宽度间距
				horizontalWidth = mHorizontalSpacing;
			} else if (!mIsNeedGrep && isFirst) {
				isFirst = false;
				lineHeight = Math.max(lineHeight, measuredHeight);
				lineWidth += (measuredWidth + horizontalWidth);
				horizontalWidth = mHorizontalSpacing;
			} else {
				isFirst = true;
				maxParams[0] = maxParams[0] > lineWidth ? maxParams[0]
						: lineWidth;
				maxParams[1] += (lineHeight + verticalHeight);
				verticalHeight = mVerticalSpacing;// 第二行开始每行增加间距
				if (++currentLine >= mMaxLine) {
					return maxParams;
				}
				lineWidth = measuredWidth;
				lineHeight = measuredHeight;
			}

			if (mViews.size() > currentLine) {
				arrayList = mViews.get(currentLine);
			} else {
				arrayList = new ArrayList();
				mViews.add(arrayList);
			}
			arrayList.add(childView);
		}

		maxParams[0] = maxParams[0] > lineWidth ? maxParams[0] : lineWidth;
		maxParams[1] += (lineHeight + verticalHeight);// 加上最后一行的最大高度
		return maxParams;
	}

	private void measureChildView(View childView) {
		int cwMeasureSpec = MeasureSpec.UNSPECIFIED;
		int chMeasureSpec = MeasureSpec.UNSPECIFIED;
		ViewGroup.LayoutParams lp = childView.getLayoutParams();
		if (lp.width >= 0) {
			cwMeasureSpec = MeasureSpec.makeMeasureSpec(lp.width,
					MeasureSpec.AT_MOST);
		}
		if (lp.height >= 0) {
			chMeasureSpec = MeasureSpec.makeMeasureSpec(lp.height,
					MeasureSpec.AT_MOST);
		}
		childView.measure(cwMeasureSpec, chMeasureSpec);
	}

	@Override
	protected void onLayout(boolean changed, int l, int t, int r, int b) {

		int left = getPaddingLeft();
		int top = getPaddingTop();
		int lineHeight = 0;
		int startHeight = top;

		for (ArrayList list : mViews) {
			for (View view : list) {
				int viewLeftMargin = 0;
				if (view.getLayoutParams() instanceof LinearLayout.LayoutParams) {
					LinearLayout.LayoutParams viewLayoutParams = (LinearLayout.LayoutParams) view
							.getLayoutParams();
					viewLeftMargin = viewLayoutParams.leftMargin;
				}

				int measuredHeight = view.getMeasuredHeight();
				int measuredWidth = view.getMeasuredWidth();
				if (viewLeftMargin < 0) {
					view.layout(viewLeftMargin + left - mHorizontalSpacing,
							startHeight, viewLeftMargin + left + measuredWidth,
							startHeight + measuredHeight);
				} else {
					view.layout(left, startHeight, left + measuredWidth,
							startHeight + measuredHeight);
				}
				left += (view.getMeasuredWidth() + mHorizontalSpacing);
				lineHeight = Math.max(measuredHeight, lineHeight);
			}
			startHeight = startHeight + lineHeight + mVerticalSpacing;
			left = getPaddingLeft();
		}

	}

	// 以下方法全部使用init来设置属性，避免set，build方法和继承的方法的方法名相似，不好找

	public HotelTagsView initHorizontalSpacing(int horizontalSpacing) {
		this.mHorizontalSpacing = horizontalSpacing;
		return this;
	}

	/**
	 * 设置标签显示的最大宽度
	 *
	 * @param maxWidth
	 */
	public HotelTagsView initMaxWidth(int maxWidth) {
		this.mMaxWidth = maxWidth;
		return this;
	}

	/**
	 * 每行最后一个展示不全的标签是否显示出来
	 * 
	 * @param isNeedGrep
	 */
	public HotelTagsView initIsNeedGrep(boolean isNeedGrep) {
		this.mIsNeedGrep = isNeedGrep;
		return this;
	}

	/**
	 * 是否支持多行
	 * 
	 * @param isCanMulti
	 * @return
	 */
	public HotelTagsView initIsCanMulti(boolean isCanMulti) {
		this.mIsCanMulti = isCanMulti;
		if (!mIsCanMulti) {
			mMaxLine = 1;
		}
		return this;
	}

	/**
	 * mainView如果显示不开，则第二行显示
	 *
	 * @param view
	 */
	public HotelTagsView initMainTagView(View view) {
		this.mMainView = view;
		return this;
	}

	/**
	 * 最大行数
	 * 
	 * @param maxLine
	 * @return
	 */
	public HotelTagsView initMaxLine(int maxLine) {
		this.mMaxLine = maxLine;
		return this;
	}

	/**
	 * 宽度自适应
	 * 
	 * @return
	 */
	public HotelTagsView initWarpWidth(boolean warpWidth) {
		this.mWarpWidth = warpWidth;
		return this;
	}

}

工程如下：

http://download.csdn.net/detail/aa5279aa/9509705

如需转载，请标明出处：http://write.blog.csdn.net/postedit/51313712