自定义流式布局

最新推荐文章于 2023-11-03 15:07:01 发布

原创最新推荐文章于 2023-11-03 15:07:01 发布 · 233 阅读

CC 4.0 BY-SA版权

本文介绍如何通过继承ViewGroup创建自定义布局，并重写onMeasure和onLayout方法来实现动态调整子视图的位置和大小。具体包括：1. 创建继承ViewGroup的类；2. 重写onMeasure进行测量；3. 重写onLayout进行布局。

不知道在哪个博客里看到的整理了一遍

创建一个继承ViewGroup的类

public class SearchView extends ViewGroup

重写onMeasure

@Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        //测量
        measureChildren(widthMeasureSpec, heightMeasureSpec);
    }

重写onLayout

    int left_back=20;
    int back=20;
 @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        //上边距
        int up_below_back=back;
        //左边距
        int around_back=left_back;
        for (int i =0;i<getChildCount();i++){
            //获取宽高
            int measuredHeight = getChildAt(i).getMeasuredHeight();
            int measuredWidth = getChildAt(i).getMeasuredWidth();
            //判断
            if (measuredWidth+left_back+around_back>getWidth()){
                around_back=20;
                up_below_back+=back+measuredHeight;
                getChildAt(i).layout(around_back,up_below_back,around_back+measuredWidth,up_below_back+measuredHeight);
            }else{
                getChildAt(i).layout(around_back,up_below_back,around_back+measuredWidth,up_below_back+measuredHeight);
            }
            around_back+=left_back+measuredWidth;

        }
    }

具体的使用

        //找到自定义的类
        <com.mod.SearchView
        android:id="@+id/search"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        </com.mod.SearchView>
             //获取内容
                String trim = et_search.getText().toString().trim();
                //创建一个TextView
                TextView textView = new TextView(SearchActivity.this);
                textView.setBackgroundResource(R.drawable.shop_30);
                //把内容添加到TextView
                textView.setText(trim);
                //设置自定义大小
                ViewGroup.MarginLayoutParams params = new ViewGroup.MarginLayoutParams(
                        ViewGroup.MarginLayoutParams.WRAP_CONTENT,
                        ViewGroup.MarginLayoutParams.WRAP_CONTENT
                );
                //把TextView和大小传过去
                search.addView(textView,params);