package com.fuban.user.views;
|
|
import android.content.Context;
|
import android.content.res.TypedArray;
|
import android.util.AttributeSet;
|
import android.view.View;
|
import android.view.ViewGroup;
|
|
import com.fuban.user.R;
|
|
|
/**
|
* Created by lmw on 2016/11/8.
|
*/
|
|
public class FlowLayout extends ViewGroup{
|
private float mVerticalSpacing; //每个item纵向间距
|
private float mHorizontalSpacing; //每个item横向间距
|
public FlowLayout(Context context) {
|
this(context,null);
|
}
|
|
public FlowLayout(Context context, AttributeSet attrs, int defStyleAttr) {
|
super(context, attrs, defStyleAttr);
|
inial(context,attrs);
|
}
|
|
public FlowLayout(Context context, AttributeSet attrs) {
|
this(context, attrs,0);
|
inial(context,attrs);
|
}
|
|
public void setHorizontalSpacing(float pixelSize) {
|
mHorizontalSpacing = pixelSize;
|
}
|
public void setVerticalSpacing(float pixelSize) {
|
mVerticalSpacing = pixelSize;
|
}
|
|
@Override
|
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
|
//获取容器设置的padding
|
int mPaddingLeft = getPaddingLeft();
|
int mPaddingRight = getPaddingRight();
|
int mPaddingTop = getPaddingTop();
|
int mPaddingBottom = getPaddingBottom();
|
//获取布局要求给的宽度大小
|
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
|
//获取布局要求给的 高度的mode
|
int heightMode = MeasureSpec.getMode(heightMeasureSpec);
|
//获取布局要求给的 高度大小
|
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
|
|
//容器存放所有子View所需的总高度
|
int totalHeight = mPaddingTop + mPaddingBottom;
|
//某行已使用的宽度
|
int lineUsedSize = mPaddingLeft + mPaddingRight;
|
//用来保存某行最后占的高度，需要取同一行中最高的子View的高度
|
int lineHeight = 0;
|
|
//循环遍历每一个子View
|
for (int i = 0; i < getChildCount(); i++) {
|
View child = getChildAt(i);
|
if(child.getVisibility() == GONE){
|
//如果子View被设置为隐藏，就跳过这个子View
|
continue;
|
}
|
//让子View自己去测量自己，测量之后就可以调用子View的getMeasureWidth方法获取到测量宽
|
measureChild(child,widthMeasureSpec,heightMeasureSpec);
|
int childWidth = child.getMeasuredWidth(); //获取子View的测量宽
|
int childHeight = child.getMeasuredHeight(); //获取子View的测量高
|
//获取子View的布局参数LayoutParams
|
MarginLayoutParams mlps = (MarginLayoutParams) child.getLayoutParams();
|
//计算这个孩子一共需要多少空间
|
int spaceWidth = childWidth + mlps.leftMargin + mlps.rightMargin;
|
int spaceHeight = childHeight + mlps.topMargin + mlps.bottomMargin;
|
|
if(lineUsedSize + spaceWidth <= widthSize){
|
lineUsedSize += spaceWidth + mHorizontalSpacing;
|
//只要子View的高度大与之前保存的行高，就将子View的高度赋值给行高
|
if(spaceHeight > lineHeight){
|
lineHeight = spaceHeight;
|
}
|
}else{ //这个子View不够摆放，将放到下一行
|
totalHeight += lineHeight + mVerticalSpacing;
|
lineUsedSize = mPaddingLeft + mPaddingRight + spaceWidth;
|
lineHeight = spaceHeight;
|
}
|
}
|
if(heightMode == MeasureSpec.EXACTLY){
|
totalHeight = heightSize;
|
}else{
|
totalHeight += lineHeight;
|
}
|
setMeasuredDimension(widthSize,totalHeight);
|
}
|
|
/**
|
* 给子控件布局，也就是设置子控件在容器中的位置
|
* @param changed
|
* @param l
|
* @param t
|
* @param r
|
* @param b
|
*/
|
@Override
|
protected void onLayout(boolean changed, int l, int t, int r, int b) {
|
//获取给容器设置的padding
|
int mPaddingLeft = getPaddingLeft();
|
int mPaddingRight = getPaddingRight();
|
int mPaddingTop = getPaddingTop();
|
//子View
|
int lineX = mPaddingLeft;
|
int lineY = mPaddingTop;
|
int lineWidth = r - l;
|
//某行已使用的宽度
|
int lineUsed = mPaddingLeft + mPaddingRight;
|
int lineHeight = 0;
|
for (int i = 0; i < this.getChildCount(); i++) {
|
View child = this.getChildAt(i);
|
if (child.getVisibility() == GONE) {
|
continue;
|
}
|
int childWidth = child.getMeasuredWidth(); //获取子View的测量宽
|
int childHeight = child.getMeasuredHeight(); //获取子View的测量高
|
//获取子View的布局参数LayoutParams
|
MarginLayoutParams mlps = (MarginLayoutParams) child.getLayoutParams();
|
//计算这个孩子一共需要多少空间
|
int spaceWidth = childWidth + mlps.leftMargin + mlps.rightMargin;
|
int spaceHeight = childHeight + mlps.topMargin + mlps.bottomMargin;
|
|
if(lineUsed + spaceWidth > lineWidth){ //不够放了
|
lineY += lineHeight + mVerticalSpacing;
|
//变量的重新设置
|
lineUsed = mPaddingLeft + mPaddingRight;
|
lineX = mPaddingLeft;
|
lineHeight = 0;
|
}
|
//设置子View在容器中的位置
|
child.layout(lineX+mlps.leftMargin,lineY+mlps.topMargin,lineX+mlps.leftMargin+childWidth,lineY+mlps.topMargin+childHeight);
|
if(spaceHeight > lineHeight){
|
lineHeight = spaceHeight;
|
}
|
lineUsed += spaceWidth + mHorizontalSpacing;
|
lineX += spaceWidth + mHorizontalSpacing;
|
}
|
}
|
|
@Override
|
protected LayoutParams generateLayoutParams(LayoutParams p) {
|
return new MarginLayoutParams(p);
|
}
|
|
@Override
|
public LayoutParams generateLayoutParams(AttributeSet attrs)
|
{
|
return new MarginLayoutParams(getContext(), attrs);
|
}
|
|
@Override
|
protected LayoutParams generateDefaultLayoutParams() {
|
return new MarginLayoutParams(super.generateDefaultLayoutParams());
|
}
|
|
/**
|
* 初始化自定义属性
|
* @param context
|
* @param attrs
|
*/
|
private void inial(Context context,AttributeSet attrs) {
|
TypedArray typedArray = context.obtainStyledAttributes(attrs, R.styleable.FlowLayout);
|
float horizontal = typedArray.getDimension(R.styleable.FlowLayout_HorizontalSpacing,15);
|
float verticel = typedArray.getDimension(R.styleable.FlowLayout_VerticalSpacing,15);
|
setHorizontalSpacing(horizontal);
|
setVerticalSpacing(verticel);
|
typedArray.recycle();
|
|
}
|
}
|
