package com.mcxtzhang.zxtcommonlib.widget.FlowLayout;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
/**
* 流式布局
* Created by zhangxutong on 2016/1/17.
* 1 增加点击事件
* 2 增加Adapter
* Updated by zhangxutong on 2016/10/11
*/
public class FlowViewGroup extends ViewGroup {
private static final String TAG = "zxt/FlowViewGroup";
private FlowBaseAdapter mAdapter;
public FlowViewGroup(Context context) {
this(context, null);
}
public FlowViewGroup(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public FlowViewGroup(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
}
//在onMeasure里，测量所有子View的宽高，以及确定Viewgroup自己的宽高。
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
//获取系统传递过来测量出的宽度 高度，以及相应的测量模式。
//如果测量模式为 EXACTLY( 确定的dp值，match_parent)，则可以调用setMeasuredDimension()设置，
//如果测量模式为 AT_MOST(wrap_content),则需要经过计算再去调用setMeasuredDimension()设置
int widthMeasure = MeasureSpec.getSize(widthMeasureSpec);
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
int heightMeasure = MeasureSpec.getSize(heightMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
//计算宽度 高度 //wrap_content测量模式下会使用到:
//存储最后计算出的宽度，
int maxLineWidth = 0;
//存储最后计算出的高度
int totalHeight = 0;
//存储当前行的宽度
int curLineWidth = 0;
//存储当前行的高度
int curLineHeight = 0;
// 得到内部元素的个数
int count = getChildCount();
//存储子View
View child = null;
//存储子View的LayoutParams
MarginLayoutParams params = null;
//子View Layout需要的宽高(包含margin)，用于计算是否越界
int childWidth;
int childHeight;
//遍历子View 计算父控件宽高
for (int i = 0; i < count; i++) {
child = getChildAt(i);
//如果gone，不测量了
if (View.GONE == child.getVisibility()) {
continue;
}
//先测量子View
measureChild(child, widthMeasureSpec, heightMeasureSpec);
//获取子View的LayoutParams，(子View的LayoutParams的对象类型，取决于其ViewGroup的generateLayoutParams()方法的返回的对象类型，这里返回的是MarginLayoutParams)
params = (MarginLayoutParams) child.getLayoutParams();
//子View需要的宽度 为 子View 本身宽度+marginLeft + marginRight
childWidth = child.getMeasuredWidth() + params.leftMargin + params.rightMargin;
childHeight = child.getMeasuredHeight() + params.topMargin + params.bottomMargin;
//Log.i(TAG, "子View Layout需要的宽高(包含margin)：childWidth:" + childWidth + " ,childHeight:" + childHeight);
//如果当前的行宽度大于 父控件允许的最大宽度 则要换行
//父控件允许的最大宽度 如果要适配 padding 这里要- getPaddingLeft() - getPaddingRight()
//即为测量出的宽度减去父控件的左右边距
if (curLineWidth + childWidth > widthMeasure - getPaddingLeft() - getPaddingRight()) {
//通过比较 当前行宽 和以前存储的最大行宽,得到最新的最大行宽,用于设置父控件的宽度
maxLineWidth = Math.max(maxLineWidth, curLineWidth);
//父控件的高度增加了，为当前高度+当前行的高度
totalHeight += curLineHeight;
//换行后 刷新 当前行 宽高数据： 因为新的一行就这一个View，所以为当前这个view占用的宽高(要加上View 的 margin)
curLineWidth = childWidth;
curLineHeight = childHeight;
} else {
//不换行：叠加当前行宽 和 比较当前行高:
curLineWidth += childWidth;
curLineHeight = Math.max(curLineHeight, childHeight);
}
//如果已经是最后一个View,要比较当前行的 宽度和最大宽度，叠加一共的高度
if (i == count - 1) {
maxLineWidth = Math.max(maxLineWidth, curLineWidth);
totalHeight += childHeight;
}
}
//Log.i(TAG, "系统测量允许的尺寸最大值：widthMeasure:" + widthMeasure + " ,heightMeasure:" + heightMeasure);
//Log.i(TAG, "经过我们测量实际的尺寸(不包括父控件的padding)：maxLineWidth:" + maxLineWidth + " ,totalHeight:" + totalHeight);
//Log.i(TAG, "heightMode == MeasureSpec.AT_MOST:" +(heightMode == MeasureSpec.AT_MOST));
//Log.i(TAG, "heightMode == MeasureSpec.EXACTLY:" +(heightMode == MeasureSpec.EXACTLY));
//Log.i(TAG, "heightMode == MeasureSpec.UNSPECIFIED:" +(heightMode == MeasureSpec.UNSPECIFIED));
//适配padding,如果是wrap_content,则除了子控件本身占据的控件，还要在加上父控件的padding
setMeasuredDimension(
widthMode != MeasureSpec.EXACTLY ? maxLineWidth + getPaddingLeft() + getPaddingRight() : widthMeasure,
heightMode != MeasureSpec.EXACTLY ? totalHeight + getPaddingTop() + getPaddingBottom() : heightMeasure);//fix by zhangxutong 有些页面太长了
}
//布局父控件位置以及子控件的位置
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
//Log.i(TAG, "changed:" + changed + " ,l:" + l + " t:" + t + " r:" + r + " b:" + b);
//子控件的个数
int count = getChildCount();
//ViewParent宽度(包含padding)
int width = getWidth();
//ViewParent 的右边x的布局限制值
int rightLimit = width - getPaddingRight();
//存储基准的left top (子类.layout(),里的坐标是基于父控件的坐标，所以 x应该是从0+父控件左内边距开始，y从0+父控件上内边距开始)
int baseLeft = 0 + getPaddingLeft();
int baseTop = 0 + getPaddingTop();
//存储现在的left top
int curLeft = baseLeft;
int curTop = baseTop;
//子View
View child = null;
//子view用于layout的 l t r b
int viewL, viewT, viewR, viewB;
//子View的LayoutParams
MarginLayoutParams params = null;
//子View Layout需要的宽高(包含margin)，用于计算是否越界
int childWidth;
int childHeight;
//子View 本身的宽高
int childW, childH;
//临时增加一个temp 存储上一个View的高度 解决过长的两行View导致显示不正确的bug
int lastChildHeight = 0;
//
for (int i = 0; i < count; i++) {
child = getChildAt(i);
//add by zhangxutong 2016 10 11 begin:Feature 1:点击事件
final int finalI = i;
child.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if (null != mOnItemClickListener) {
mOnItemClickListener.onItemClick(v, finalI, FlowViewGroup.this);
}
}
});
//add by zhangxutong 2016 10 11 end
//如果gone，不布局了
if (View.GONE == child.getVisibility()) {
continue;
}
//获取子View本身的宽高:
childW = child.getMeasuredWidth();
childH = child.getMeasuredHeight();
//获取子View的LayoutParams，用于获取其margin
params = (MarginLayoutParams) child.getLayoutParams();
//子View需要的宽高 为 本身宽高+marginLeft + marginRight
childWidth = childW + params.leftMargin + params.rightMargin;
childHeight = childH + params.topMargin + params.bottomMargin;
//这里要考虑padding，所以右边界为 ViewParent宽度(包含padding) -ViewParent右内边距
if (curLeft + childWidth > rightLimit) {
//如果当前行已经放不下该子View了 需要换行放置：
//在新的一行布局子View，左x就是baseLeft，上y是 top +前一行高(这里假设的是每一行行高一样)，
curTop = curTop + lastChildHeight;
//layout时要考虑margin
viewL = baseLeft + params.leftMargin;
viewT = curTop + params.topMargin;
viewR = viewL + childW;
viewB = viewT + childH;
//child.layout(baseLeft + params.leftMargin, curTop + params.topMargin, baseLeft + params.leftMargin + child.getMeasuredWidth(), curTop + params.topMargin + child.getMeasuredHeight());
//Log.i(TAG,"新的一行:" +" ,baseLeft:"+baseLeft +" curTop:"+curTop+" baseLeft+childWidth:"+(baseLeft+childWidth)+" curTop+childHeight:"+ ( curTop+childHeight));
curLeft = baseLeft + childWidth;
} else {
//当前行可以放下子View:
viewL = curLeft + params.leftMargin;
viewT = curTop + params.topMargin;
viewR = viewL + childW;
viewB = viewT + childH;
//child.layout(curLeft + params.leftMargin, curTop + params.topMargin, curLeft + params.leftMargin + child.getMeasuredWidth(), curTop + params.topMargin + child.getMeasuredHeight());
//Log.i(TAG,"当前行:"+changed +" ,curLeft:"+curLeft +" curTop:"+curTop+" curLeft+childWidth:"+(curLeft+childWidth)+" curTop+childHeight:"+(curTop+childHeight));
curLeft = curLeft + childWidth;
}
lastChildHeight = childHeight;
//布局子View
child.layout(viewL, viewT, viewR, viewB);
}
}
/**
* @return 当前ViewGroup返回的Params的类型
*/
@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new MarginLayoutParams(getContext(), attrs);
}
/**
* 外部调用 同时刷新视图
*
* @param mAdapter
*/
public void setAdapter(FlowBaseAdapter mAdapter) {
this.mAdapter = mAdapter;
updateUI();
}
/**
* 刷新UI
*/
public void updateUI() {
removeAllViews();
int count = mAdapter.getCount();
if (null != mAdapter && count > 0) {
for (int i = 0; i < count; i++) {
View child = mAdapter.getView(this, i);
addView(child);
}
}
}
//看名字
public interface OnItemClickListener {
void onItemClick(View view, int pos, FlowViewGroup parent);
}
private OnItemClickListener mOnItemClickListener;
public OnItemClickListener getOnItemClickListener() {
return mOnItemClickListener;
}
public FlowViewGroup setOnItemClickListener(OnItemClickListener onItemClickListener) {
mOnItemClickListener = onItemClickListener;
return this;
}
}