FlowLayout流式布局

FlowLayout

效果图

每个textview根据里面文字的多少,自动调整大小.当一行被填满或者无法再填充一个单独的textview的时候,就换行. 

使用方法

在activity的onCreate()方法中添加initData()方法

public void initData(){    LayoutInflater mInflater = LayoutInflater.from(this);        //我忘了为什么了,但是一定要用这种加载布局的方式.使用View.inflate()会报错. (我现在很尴尬 --')    for (int i = 0; i < mVals.length; i++)    {        TextView tv = (TextView) mInflater.inflate(R.layout.tv,                mFlowLayout, false);        tv.setText(mVals[i]);        mFlowLayout.addView(tv);    }}

其中,mFlowLayout就是我们下面代码的FlowLayout.

其在Activity中的布局文件中长这个样子(很普通的自定义控件的写法 : 包名+类名)

<包名.FlowLayout            android:id="@+id/flowlayout"            android:layout_width="match_parent"            android:layout_height="wrap_content"             />

FlowLayout的代码

public class FlowLayout extends ViewGroup{    public FlowLayout(Context context, AttributeSet attrs, int defStyle)    {        super(context, attrs, defStyle);        //    }    public FlowLayout(Context context, AttributeSet attrs)    {        this(context, attrs, 0);    }    public FlowLayout(Context context)    {        this(context, null);    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)    {        int sizeWidth = MeasureSpec.getSize(widthMeasureSpec);        int modeWidth = MeasureSpec.getMode(widthMeasureSpec);        int sizeHeight = MeasureSpec.getSize(heightMeasureSpec);        int modeHeight = MeasureSpec.getMode(heightMeasureSpec);        // wrap_content        int width = 0;        int height = 0;        // 记录每一行的宽度与高度        int lineWidth = 0;        int lineHeight = 0;        // 得到内部元素的个数        int cCount = getChildCount();        for (int i = 0; i < cCount; i++)        {            View child = getChildAt(i);            // 测量子View的宽和高            measureChild(child, widthMeasureSpec, heightMeasureSpec);            // 得到LayoutParams            MarginLayoutParams lp = (MarginLayoutParams) child                    .getLayoutParams();            // 子View占据的宽度            int childWidth = child.getMeasuredWidth() + lp.leftMargin                    + lp.rightMargin;            // 子View占据的高度            int childHeight = child.getMeasuredHeight() + lp.topMargin                    + lp.bottomMargin;            // 换行            if (lineWidth + childWidth > sizeWidth - getPaddingLeft() - getPaddingRight())            {                // 对比得到最大的宽度                width = Math.max(width, lineWidth);                // 重置lineWidth                lineWidth = childWidth;                // 记录行高                height += lineHeight;                lineHeight = childHeight;            } else            // 未换行            {                // 叠加行宽                lineWidth += childWidth;                // 得到当前行最大的高度                lineHeight = Math.max(lineHeight, childHeight);            }            // 最后一个控件            if (i == cCount - 1)            {                width = Math.max(lineWidth, width);                height += lineHeight;            }        }        Log.e("TAG", "sizeWidth = " + sizeWidth);        Log.e("TAG", "sizeHeight = " + sizeHeight);        setMeasuredDimension(                //                modeWidth == MeasureSpec.EXACTLY ? sizeWidth : width + getPaddingLeft() + getPaddingRight(),                modeHeight == MeasureSpec.EXACTLY ? sizeHeight : height + getPaddingTop()+ getPaddingBottom()//        );    }    /**     * 存储所有的View     */    private List<List<View>> mAllViews = new ArrayList<List<View>>();    /**     * 每一行的高度     */    private List<Integer> mLineHeight = new ArrayList<Integer>();    @Override    protected void onLayout(boolean changed, int l, int t, int r, int b)    {        mAllViews.clear();        mLineHeight.clear();        // 当前ViewGroup的宽度        int width = getWidth();        int lineWidth = 0;        int lineHeight = 0;        List<View> lineViews = new ArrayList<View>();        int cCount = getChildCount();        for (int i = 0; i < cCount; i++)        {            View child = getChildAt(i);            MarginLayoutParams lp = (MarginLayoutParams) child                    .getLayoutParams();            int childWidth = child.getMeasuredWidth();            int childHeight = child.getMeasuredHeight();            // 如果需要换行            if (childWidth + lineWidth + lp.leftMargin + lp.rightMargin > width - getPaddingLeft() - getPaddingRight())            {                // 记录LineHeight                mLineHeight.add(lineHeight);                // 记录当前行的Views                mAllViews.add(lineViews);                // 重置我们的行宽和行高                lineWidth = 0;                lineHeight = childHeight + lp.topMargin + lp.bottomMargin;                // 重置我们的View集合                lineViews = new ArrayList<View>();            }            lineWidth += childWidth + lp.leftMargin + lp.rightMargin;            lineHeight = Math.max(lineHeight, childHeight + lp.topMargin                    + lp.bottomMargin);            lineViews.add(child);        }// for end        // 处理最后一行        mLineHeight.add(lineHeight);        mAllViews.add(lineViews);        // 设置子View的位置        int left = getPaddingLeft();        int top = getPaddingTop();        // 行数        int lineNum = mAllViews.size();        for (int i = 0; i < lineNum; i++)        {            // 当前行的所有的View            lineViews = mAllViews.get(i);            lineHeight = mLineHeight.get(i);            for (int j = 0; j < lineViews.size(); j++)            {                View child = lineViews.get(j);                // 判断child的状态                if (child.getVisibility() == View.GONE)                {                    continue;                }                MarginLayoutParams lp = (MarginLayoutParams) child                        .getLayoutParams();                int lc = left + lp.leftMargin;                int tc = top + lp.topMargin;                int rc = lc + child.getMeasuredWidth();                int bc = tc + child.getMeasuredHeight();                // 为子View进行布局                child.layout(lc, tc, rc, bc);                left += child.getMeasuredWidth() + lp.leftMargin                        + lp.rightMargin;            }            left = getPaddingLeft() ;            top += lineHeight ;        }    }    /**     * 与当前ViewGroup对应的LayoutParams     */    @Override    public LayoutParams generateLayoutParams(AttributeSet attrs)    {        return new MarginLayoutParams(getContext(), attrs);    }}