欲实现如下效果：
思路很简单就2步：
1、测量出ViewGroup的大小
2、找出子View的位置
若要实现动态添加标签view，就要实现ViewGroup的onMeasure（）、onLayout（）方法，这两个方法可由该ViewGroup的requestLayout（）方法触发，
onMeasure是对ViewGroup的大小计算，onLayout是针对View（可以是子View也可以是本View）的位置设置
关于这几个方法的流程图如下：
/** * 流式标签(动态的，根据传入的数据动态添加标签) */ public class CustomerFlowLayout extends ViewGroup { private List<String> mTags = new ArrayList<String>(); public CustomerFlowLayout(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); } public CustomerFlowLayout(Context context, AttributeSet attrs) { super(context, attrs); } public CustomerFlowLayout(Context context) { super(context); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int widthMode = MeasureSpec.getMode(widthMeasureSpec); int widthSize = MeasureSpec.getSize(widthMeasureSpec); int heightMode = MeasureSpec.getMode(heightMeasureSpec); int heightSize = MeasureSpec.getSize(heightMeasureSpec); //当前ViewGroup的总高度 int totalHeight= 0; //所有行中的最大宽度 int maxLineWidth = 0; //当前行的最大高度 int lineMaxHeight = 0; //当前行的总宽度 int currentLineWidth = 0; //每个childView所占用的宽度 int childViewWidthSpace = 0; //每个childView所占用的高度 int childViewHeightSpace = 0; int count = getChildCount(); MarginLayoutParams layoutParams; for(int i = 0; i < count; i++){ View child = getChildAt(i); if(child.getVisibility() != View.GONE){//只有当这个View能够显示的时候才去测量 //测量每个子View，以获取子View的宽和高 measureChild(child, widthMeasureSpec, heightMeasureSpec); layoutParams = (MarginLayoutParams) child.getLayoutParams(); childViewWidthSpace = child.getMeasuredWidth() + layoutParams.leftMargin + layoutParams.rightMargin; childViewHeightSpace = child.getMeasuredHeight() + layoutParams.topMargin + layoutParams.bottomMargin; if(currentLineWidth + childViewWidthSpace > widthSize){//表示如果当前行再加上现在这个子View，就会超出总的规定宽度，需要另起一行 totalHeight += lineMaxHeight; if(maxLineWidth < currentLineWidth){//如果行的最长宽度发生了变化，更新保存的最长宽度 maxLineWidth = currentLineWidth; } currentLineWidth = childViewWidthSpace;//另起一行后，需要重置当前行宽 lineMaxHeight = childViewHeightSpace; }else{//表示当前行可以继续添加子元素 currentLineWidth += childViewWidthSpace; if(lineMaxHeight < childViewHeightSpace){ lineMaxHeight = childViewHeightSpace; } } } } setMeasuredDimension(widthMode == MeasureSpec.EXACTLY ? widthSize : maxLineWidth, heightMode == MeasureSpec.EXACTLY ? heightSize : totalHeight); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { //当前是第几行 int currentLine = 1; //存放每一行的最大高度 List<Integer> lineMaxHeightList = new ArrayList<Integer>(); //每个childView所占用的宽度 int childViewWidthSpace = 0; //每个childView所占用的高度 int childViewHeightSpace = 0; //当前行的最大高度 int lineMaxHeight = 0; //当前行的总宽度 int currentLineWidth = 0; int count = getChildCount(); MarginLayoutParams layoutParams; for(int i = 0; i < count; i++){ int cl= 0, ct = 0, cr = 0, cb = 0; View child = getChildAt(i); if(child.getVisibility() != View.GONE){//只有当这个View能够显示的时候才去测量 layoutParams = (MarginLayoutParams) child.getLayoutParams(); childViewWidthSpace = child.getMeasuredWidth() + layoutParams.leftMargin + layoutParams.rightMargin; childViewHeightSpace = child.getMeasuredHeight() + layoutParams.topMargin + layoutParams.bottomMargin; System.out.println("getWidth()---->"+getWidth()); if(currentLineWidth + childViewWidthSpace > getWidth()){//表示如果当前行再加上现在这个子View，就会超出总的规定宽度，需要另起一行 lineMaxHeightList.add(lineMaxHeight);//此时先将这一行的最大高度加入到集合中 //新的一行，重置一些参数 currentLine++; currentLineWidth = childViewWidthSpace; lineMaxHeight = childViewHeightSpace; cl = layoutParams.leftMargin; if(currentLine > 1){ for(int j = 0; j < currentLine - 1; j++){ ct += lineMaxHeightList.get(j); } ct += layoutParams.topMargin ; }else{ ct = layoutParams.topMargin; } }else{//表示当前行可以继续添加子元素 cl = currentLineWidth + layoutParams.leftMargin; if(currentLine > 1){ for(int j = 0; j < currentLine - 1; j++){ ct += lineMaxHeightList.get(j); } ct += layoutParams.topMargin; }else{ ct = layoutParams.topMargin; } currentLineWidth += childViewWidthSpace; if(lineMaxHeight < childViewHeightSpace){ lineMaxHeight = childViewHeightSpace; } } cr = cl + child.getMeasuredWidth(); cb = ct + child.getMeasuredHeight(); child.layout(cl, ct, cr, cb); } } } @Override public LayoutParams generateLayoutParams(AttributeSet attrs) { return new MarginLayoutParams(getContext(), attrs); } public void setTags(List<String> tags){ if(tags!= null){ mTags.clear(); mTags.addAll(tags); for(int i = 0; i < mTags.size(); i++){ TextView tv = new TextView(getContext()); MarginLayoutParams lp = new MarginLayoutParams(MarginLayoutParams.WRAP_CONTENT, MarginLayoutParams.WRAP_CONTENT); lp.setMargins(15, 15, 15, 15); // lp.width = MarginLayoutParams.WRAP_CONTENT; // lp.height = MarginLayoutParams.WRAP_CONTENT; tv.setLayoutParams(lp); tv.setBackgroundResource(R.drawable.tv_bg); /* * setPadding一定要在setBackgroundResource后面使用才有效！！！ * http://stackoverflow.com/questions/18327498/setting-padding-for-textview-not-working */ tv.setPadding(15, 15, 15, 15); tv.setTextColor(Color.WHITE); tv.setText(mTags.get(i)); tv.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { if(listener != null){ listener.onClick(v); } } }); addView(tv); } requestLayout(); } } private OnTagItemClickListener listener; public interface OnTagItemClickListener{ public void onClick(View v); } public void setOnTagItemClickListener(OnTagItemClickListener l){ listener = l; } }
针对在Activity中的使用：
public class MainActivity extends Activity { private CustomerFlowLayout customerFlowLayout; List<String> tags = new ArrayList<String>(); @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_dynamic_tagflowlayout); CustomerFlowLayout = (CustomerFlowLayout) findViewById(R.id.dynamic_tag); customerFlowLayout.setOnTagItemClickListener(new OnTagItemClickListener() { @Override public void onClick(View v) { TextView tv = (TextView) v; Toast.makeText(MainActivity.this, tv.getText().toString(), Toast.LENGTH_SHORT).show(); } }); initData(); customerFlowLayout.setTags(tags); } private void initData() { tags.add("阳哥你好！"); tags.add("Android开发"); tags.add("新闻热点"); tags.add("热水进宿舍啦！"); tags.add("I love you"); tags.add("成都妹子"); tags.add("新余妹子"); tags.add("仙女湖"); tags.add("创新工厂"); tags.add("孵化园"); tags.add("神州100发射"); tags.add("有毒疫苗"); tags.add("顶你阳哥阳哥"); tags.add("Hello World"); tags.add("闲逛的蚂蚁"); tags.add("闲逛的蚂蚁"); tags.add("闲逛的蚂蚁"); tags.add("闲逛的蚂蚁"); tags.add("闲逛的蚂蚁"); tags.add("闲逛的蚂蚁"); } }
上述的ViewGroup中可以添加 对标签的处理（例如：点击、选中）
参考资料：
https://blog.csdn.net/shakespeare001/article/details/51089128
https://www.cnblogs.com/ldq2016/p/9035332.html