基礎文章地址：http://blog.csdn.net/lmj623565791/article/details/38352503  感謝大神文章

因為要做那種流式布局標簽，查了很多資料，都是大同小異。

有些沒有解決FlowLayout的padding

的問題。很多都是直接轉載的，而且FlowLayout里面的間隔都是靠子view的margin

來解決，感覺很不科學。所以自己的就在這個基礎的封裝自己的流式布局XFlowLayout自定義的水平間隔hgap和垂直間隔vgap

整個類都有注釋，理解應該不困難

里面主要的就是onMeasure和onLayout方法，需要知道測量布局的三種模式，后面直接添加view就好

廢話不多了，直接上代碼 

主要類：

public class XFlowLayout extends ViewGroup {    //所有的子view    PRivate List<List<View>> mAllChildViews = new ArrayList<>();    //每一行的高度    private List<Integer> mLineHeight = new ArrayList<>();    //水平和垂直間距    private int hgap;    private int vgap;    public XFlowLayout(Context context) {        this(context, null);    }    public XFlowLayout(Context context, AttributeSet attrs) {        this(context, attrs, 0);    }    public XFlowLayout(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.ZBJFlowLayout);        hgap = (int) ta.getDimension(R.styleable.ZBJFlowLayout_hgap, 0);        vgap = (int) ta.getDimension(R.styleable.ZBJFlowLayout_vgap, 0);        ta.recycle();    }    //測量整個布局多大    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        //測量寬度和測量寬度模式        int sizeWidth = MeasureSpec.getSize(widthMeasureSpec);        int modeWidth = MeasureSpec.getMode(widthMeasureSpec);        //測量高度和測量高度模式        int sizeHeight = MeasureSpec.getSize(heightMeasureSpec);        int modeHeight = MeasureSpec.getMode(heightMeasureSpec);        //寬度和高度        int width = 0;        int height = 0;        //行寬和行高        int lineWidth = 0;        int lineHeight = 0;        //子view個數        int childCount = getChildCount();        for (int i = 0; i < childCount; i++) {            View child = getChildAt(i);            measureChild(child, widthMeasureSpec, heightMeasureSpec);            //獲得子view的寬高            int childWidth = child.getWidth();            int childHeight = child.getHeight();            if (lineWidth + childWidth > sizeWidth - getPaddingLeft() - getPaddingRight()) {//換行                //對比最大寬度                width = Math.max(width, lineWidth);                //換行加上垂直間隔                height += lineHeight + vgap;                //已經換行寬高重置                lineWidth = childWidth;                lineHeight = childHeight;            } else {//不換行                //不換行水平寬度加上水平間隔                lineWidth += childWidth + hgap;                //對比最大高度                lineHeight = Math.max(lineHeight, childHeight);            }            //最后一個控件            if (i == childCount - 1) {                width = Math.max(width, lineWidth);                height += lineHeight;            }            setMeasuredDimension(modeWidth == MeasureSpec.EXACTLY ? sizeWidth : width                            + getPaddingLeft() + getPaddingRight(),                    modeHeight == MeasureSpec.EXACTLY ? sizeHeight : height                            + getPaddingTop() + getPaddingBottom());        }    }    @Override    protected void onLayout(boolean changed, int l, int t, int r, int b) {        mAllChildViews.clear();        mLineHeight.clear();        //獲得當前布局的寬度        int width = getWidth();        int lineWidth = 0;        int lineHeight = 0;        List<View> lineViews = new ArrayList<View>();        int childCount = getChildCount();        for (int i = 0; i < childCount; i++) {            View child = getChildAt(i);            int childWidth = child.getMeasuredWidth();            int childHeight = child.getMeasuredHeight();            if (childWidth + lineWidth > width - getPaddingLeft() - getPaddingRight()) {//換行                //記錄行高                mLineHeight.add(lineHeight);                //記錄當前行的子view                mAllChildViews.add(lineViews);                //重置行寬高                lineWidth = 0;                lineHeight = childHeight + vgap;                //new一個新的集合                lineViews = new ArrayList<>();            }            lineWidth = lineWidth + childWidth + hgap;            lineHeight = Math.max(lineHeight, childHeight);            lineViews.add(child);        }        //處理最后一行        mLineHeight.add(lineHeight);        mAllChildViews.add(lineViews);        //記錄view位置和行數        int left = getPaddingLeft();        int top = getPaddingTop();        int lineCount = mAllChildViews.size();        for (int i = 0; i < lineCount; i++) {            //當前行所有的VIEW            lineViews = mAllChildViews.get(i);            //當前行高            lineHeight = mLineHeight.get(i);            for (int j = 0; j < lineViews.size(); j++) {                View child = lineViews.get(j);                if (child.getVisibility() == View.GONE) {//不顯示則跳出                    continue;                }                int cLeft = left;                int cTop;                if (i == 0) {                    cTop = top;                } else {                    cTop = top + vgap;                }                int cRight = cLeft + child.getMeasuredWidth();                int cBottom = cTop + child.getMeasuredHeight();                child.layout(cLeft, cTop, cRight, cBottom);                left += child.getMeasuredWidth() + hgap;            }            left = getPaddingLeft();            if (i == lineCount - 1) {                top += lineHeight + vgap;            } else {                top += lineHeight;            }        }    }//    @Override//    public ViewGroup.LayoutParams generateLayoutParams(AttributeSet attrs) {//        return new MarginLayoutParams(getContext(),attrs);//    }}attrs文件
<?xml version="1.0" encoding="utf-8"?><resources>    <declare-styleable name="ZBJFlowLayout">        <attr name="hgap" format="dimension" />        <attr name="vgap" format="dimension" />    </declare-styleable></resources>xml里面引用
        <com.expect.view.XFlowLayout            android:layout_margin="10dp"            android:padding="10dp"            android:layout_width="match_parent"            android:layout_height="wrap_content"            android:background="#5246"            zfl:hgap="10dp"            zfl:vgap="10dp">
大概就是這些了  好久沒寫博客了  不知道還能堅持到多久