流式布局

1.先写一个流式的class，代码如下：

public class MyFlow extends LinearLayout {


    private int mwidth;//得到手机的宽度
    private Context mContext;


    public MyFlow(Context context, AttributeSet attrs) {
        super(context, attrs);
        this.mContext = context;
        DisplayMetrics met = context.getResources().getDisplayMetrics();//得到手机的屏幕
        mwidth = met.widthPixels;//得到手机的宽度
        setOrientation(VERTICAL);//设置手机父级linearlayout的方向
    }

    public void setData(List<String> list) {
        LinearLayout linear = getLinear();
        for (int i = 0; i < list.size(); i++) {
            String list_item = list.get(i);
            int width = 0;   //定义一个宽度，相当于手机屏幕的宽度，因为要做比较
            int childCount = linear.getChildCount();//控件数量
            for (int j = 0; j < childCount; j++) {
                TextView tv = (TextView) linear.getChildAt(j);
                LayoutParams layoutParams = (LayoutParams) tv.getLayoutParams();
                int leftMargin = layoutParams.leftMargin;
                tv.measure(getMeasuredWidth(), getMeasuredHeight());//进行测量
                width += tv.getMeasuredWidth() + leftMargin + tv.getPaddingLeft() + tv.getPaddingRight();//计算子控件的详细大小

            }
            TextView datatext = getText();
            LayoutParams layoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

            layoutParams.leftMargin = 8;
            layoutParams.topMargin = 3;
            datatext.setLayoutParams(layoutParams);
            datatext.setText(list_item);
            datatext.measure(getMeasuredWidth(), getMeasuredHeight());

            int dataTextWidth = datatext.getMeasuredWidth() + datatext.getPaddingLeft() + datatext.getPaddingRight();

            if (mwidth>=dataTextWidth + width) {//判断如果文字长度+控件长度小于屏幕
                linear.addView(datatext);
               // list.clear();
            } else {
                linear = getLinear();
                linear.addView(datatext);
            }




        }

    }


    private LinearLayout getLinear() {//这个方法是为了创建子linearLayout的子容器，默认垂直显示
        LinearLayout linear = new LinearLayout(mContext);
        LayoutParams layoutParams = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
        linear.setLayoutParams(layoutParams);
        //linear.setOrientation(HORIZONTAL);
        this.addView(linear);//这里的this是用来表示父容器
        return linear;
    }

    private TextView getText() {
        TextView textview = new TextView(mContext);
        textview.setTextSize(20);
        textview.setTextColor(Color.RED);
        textview.setBackgroundResource(R.drawable.ignb);
        textview.setPadding(10, 10, 10, 10);
        return textview;
    }
    public void remove(){
        removeAllViews();
    }

}

2.在写一个组合式控件实现搜索历史记录



public class MyHeader extends RelativeLayout {


    private EditText edit_text;
    private Button btn_add;

    public MyHeader(Context context, AttributeSet attrs) {
        super(context, attrs);
        View v = View.inflate(context, R.layout.layout_header, this);
        edit_text=v.findViewById(R.id.edit_text);
        btn_add=v.findViewById(R.id.btn_add);
    }
    public void setEditText(String mText){
        edit_text.setText(mText);
    }
    public  Button getButton(){
        return btn_add;
    }

    public EditText getEditText() {
        return edit_text;
    }

}

3.xml文件里引入两个自定义控件：注意：头部的高需要写定高度，不然默认充满全屏

<?xml version="1.0" encoding="utf-8"?>

  <com.example.MyHeader
        android:layout_width="match_parent"
        android:layout_height="80dp"
        android:id="@+id/header"
        ></com.example.lx.rikao3.MyHeader>

<com.example.MyFlow
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/ignb"
    ></com.example.lx.rikao3.MyFlow>

4.最后在mainactivity里添加历史记录

public class MainActivity extends AppCompatActivity {

private MyHeader header;
private MyFlow ignb;
List<String> list=new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    initView();
    header.getButton().setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            EditText editText = header.getEditText();
            if(editText.getText().toString().isEmpty()){
                return;
            }
            String string = editText.getText().toString().trim();
            ignb.remove();
            list.add(string);

            ignb.setData(list);
         
        }
    });
}

private void initView() {
    header = findViewById(R.id.header);
    ignb =  findViewById(R.id.ignb);
}

}