FlowLayout

MainActivity 

 public class MainActivity extends AppCompatActivity implements View.OnClickListener {

private EditText mEtMain; private Button mBtnMain; private FlowLayout mFlMain;

@Override protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main); initView();

}

private void initView() {

mEtMain = (EditText) findViewById(R.id.et_main);

mBtnMain = (Button) findViewById(R.id.btn_main);

mFlMain = (FlowLayout) findViewById(R.id.fl_main);

mBtnMain.setOnClickListener(this);

}

@Override public void onClick(View v) {

switch (v.getId()) {

case R.id.btn_main: submit(); break;

}

}

private void submit() {

// validate

String main = mEtMain.getText().toString().trim();

if (TextUtils.isEmpty(main)) { Toast.makeText(this, "main不能为空",

Toast.LENGTH_SHORT).show(); return;

} else {

TextView textView = new TextView(getApplicationContext());

textView.setText(main);

textView.setTextColor(Color.BLACK);

textView.setPadding(10, 10, 10, 10);

mFlMain.addView(textView); } }}

FlowLayout 

public class FlowLayout extends ViewGroup {

private static final String TAG = "FlowLayout++";

public FlowLayout(Context context) {

super(context); }

public FlowLayout(Context context, AttributeSet attrs) {

this(context, attrs, 0);

}

public FlowLayout(Context context, AttributeSet attrs, int defStyleAttr) {

super(context, attrs, defStyleAttr);

}

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

//测量所有孩子的宽高

measureChildren(widthMeasureSpec, heightMeasureSpec);

int widthSize = MeasureSpec.getSize(widthMeasureSpec);

//AT-MOST

int heightSize = MeasureSpec.getSize(heightMeasureSpec);

setMeasuredDimension(widthSize, heightSize); }

@Override protected void onLayout(boolean changed, int l, int t, int r, int b) {

int lineWidth = 0;

//int lineHeight = 0;

int totalHeight = 0;

//累加的高度 View childView;

int childWidth = 0;

int childHeight = 0;

for (int i = 0; i < getChildCount(); i++)

{

childView = getChildAt(i);

childWidth = childView.getMeasuredWidth();

childHeight = childView.getMeasuredHeight();

//测量布局的宽 //换行/不换行

if (childWidth + lineWidth > getMeasuredWidth()) {

//换行

totalHeight += childHeight;

lineWidth = 0;

childViewLayout(childView, lineWidth, totalHeight, lineWidth + childWidth, totalHeight + childHeight);

//第一个

lineWidth = childWidth; }

else {

//不换行

childViewLayout(childView, lineWidth, totalHeight, lineWidth + childWidth, totalHeight + childHeight);

lineWidth += childWidth;

} } }

public void childViewLayout(View childView, int l, int t, int r, int b) { childView.layout(l, t, r, b); }}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <EditText
            android:id="@+id/et_main"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1" />

        <Button
            android:id="@+id/btn_main"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="添加" />
    </LinearLayout>

    <com.example.flowlayout.FlowLayout
        android:id="@+id/fl_main"
        android:layout_width="match_parent"
        android:layout_height="200dp">

    </com.example.flowlayout.FlowLayout>

</LinearLayout>