怎么做电商运营的基本步骤seo和sem

/**
* 通过 new FlowLayout() 代码创建
* @param context
*/
public FlowLayout(Context context) {super(context);
}/**
* 通过xml解析创建
* @param context
* @param attrs
*/
public FlowLayout(Context context, AttributeSet attrs) {super(context, attrs);
}/**
* 自定义View 默认的属性以及自定义的属性
* @param context
* @param attrs
* @param defStyleAttr
*/
public FlowLayout(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);
}

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

package com.liluj.androidui.custom;import static com.scwang.smartrefresh.layout.util.SmartUtil.dp2px;
import android.content.Context;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import com.liluj.androidui.utils.UnitConvertUtils;
import java.util.ArrayList;
import java.util.List;/**
* 自定义流式布局
*/
public class FlowLayout extends ViewGroup {//水平间隔private int horizontalSpace = dp2px(20);//垂直间隔private int veticalSpace = dp2px(20);private List<List<View>> lineViewList; //记录每行的Viewprivate List<Integer> heightList; //记录每列的高度。/*** 通过 new FlowLayout() 代码创建* @param context*/public FlowLayout(Context context) {super(context);}/*** 通过xml解析创建* @param context* @param attrs*/public FlowLayout(Context context, AttributeSet attrs) {super(context, attrs);}/*** 自定义View 默认的属性以及自定义的属性* @param context* @param attrs* @param defStyleAttr*/public FlowLayout(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);}public FlowLayout(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {super(context, attrs, defStyleAttr, defStyleRes);}private void initMeasure() {/*** 此两个参数是为了给Layout布局用的，界面不只绘制一次，会重新绘制，所以在每次执行onMeasure时要重新初始化，而不是在创建FlowLayout时初始化*/lineViewList = new ArrayList();heightList = new ArrayList<>();}/*** 依据子View的宽高 确定自己的宽高* 注意：* 1、margin值在父控件中处理* 1.1 当前ViewGroup的margin值在父控件已处理* 1.2 在度量和布局子View时要考虑margin值，否则子View的margin属性无用（此例子没处理子View的margin值）* 2、padding值包含在ViewGroup以及View的宽高* 2.1 在ViewGroup和View的 onMeasure、onLayout、onDraw时要考虑自身的padding值* @param widthMeasureSpec horizontal space requirements as imposed by the parent.*                         The requirements are encoded with*                         {@link android.view.View.MeasureSpec}.* @param heightMeasureSpec vertical space requirements as imposed by the parent.*                         The requirements are encoded with*                         {@link android.view.View.MeasureSpec}.**/@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);initMeasure();int count = getChildCount();List<View> lineView = new ArrayList<>();int lineUsedWidth = 0; //当前行已使用的宽度int lineHeight = 0; //当前行的高度int mWidth = 0;  //view的宽度int mHeight = 0; //view的高度/*** 父控件根据自己的宽高以及当前View的LayoutParam属性(宽、高、margin)分配给当前View的宽高，固定值就是固定值，* match_parent和wrap_content为父控件的宽度，*/int maxWidth = MeasureSpec.getSize(widthMeasureSpec);//子View可使用的最大宽度，需减去ViewGroup的paddingLeft和paddingRightint childrenCanUseWidth = maxWidth - getPaddingLeft()-getPaddingRight();int maxHeight = MeasureSpec.getSize(heightMeasureSpec);/*** 度量子View并计算ViewGroup属性为wrap_content时实际的宽高*/for(int i = 0;i<count;i++){View view = getChildAt(i);/*** 根据当前View的MeasureSpec属性、padding值和子View的LayoutParams值(android:layout_width和android:layout_height的属性值)来给子View分配空间*/int measureSpecWidth = getChildMeasureSpec(widthMeasureSpec,getPaddingLeft()+getPaddingRight(),view.getLayoutParams().width);int measureSpecHeight = getChildMeasureSpec(heightMeasureSpec,getPaddingTop()+getPaddingBottom(),view.getLayoutParams().height);/*** 触发子View度量自己的空间，子View度量自己的大小后校正子View的大小*/view.measure(measureSpecWidth,measureSpecHeight);int measuredWidth = view.getMeasuredWidth();int measuredHeight = view.getMeasuredHeight();//换行if(lineUsedWidth + measuredWidth > childrenCanUseWidth){lineViewList.add(lineView);heightList.add(lineHeight);mWidth = Math.max(mWidth,lineUsedWidth);mHeight = mHeight + lineHeight + veticalSpace;lineUsedWidth = 0;lineHeight = 0;lineView = new ArrayList<>();}lineView.add(view);lineUsedWidth = lineUsedWidth + measuredWidth + horizontalSpace;lineHeight = Math.max(lineHeight, measuredHeight);/*** 添加上最后一行的宽高*/if(i == count -1){lineViewList.add(lineView);heightList.add(lineHeight);mWidth = Math.max(mWidth,lineUsedWidth);mHeight = mHeight + lineHeight;}}//ViewGroup的宽高加上padding值mWidth = mWidth+getPaddingLeft()+getPaddingRight();mHeight = mHeight+getPaddingTop()+getPaddingBottom();/*** 获取当前View 宽高的mode*/int widthMode = MeasureSpec.getMode(widthMeasureSpec);int heightMode = MeasureSpec.getMode(heightMeasureSpec);/*** 当View的宽高为固定值时，使用固定值，此处固定值只会比按照wrap_content计算出来的值大，不会小，与父控件分配给当前View的宽高值有关。* 可参见ViewGroup的getChildMeasureSpec方法*/int realWidth = (widthMode == MeasureSpec.EXACTLY) ? maxWidth:mWidth;int realHeight = (heightMode == MeasureSpec.EXACTLY) ? maxHeight:mHeight;setMeasuredDimension(realWidth,realHeight);}/*** 布局子View，布局子View时使用相对坐标（相对父View进行布局）而不是绝对坐标（Window坐标系）* @param changed This is a new size or position for this view* @param l Left position, relative to parent* @param t Top position, relative to parent* @param r Right position, relative to parent* @param b Bottom position, relative to parent*/@Overrideprotected void onLayout(boolean changed, int l, int t, int r, int b) {int curL = getPaddingLeft();int curT = getPaddingTop();for(int i = 0;i< lineViewList.size();i++){List<View> lineView = lineViewList.get(i);for(int j = 0;j<lineView.size();j++){View view = lineView.get(j);int left = curL;int top = curT;int right = curL + view.getMeasuredWidth();int bottom = curT + view.getMeasuredHeight();view.layout(left,top,right,bottom);curL = right + horizontalSpace;}curL = getPaddingLeft();curT = curT + heightList.get(i)+veticalSpace;}}
}