使用获得布局文件对象,getLayoutParams 返回null

时间:2025-01-27 08:44:10

使用()获取布局文件对象,页面发现没有填充父窗体,右边有空白。

    private void init() {
        // public static View inflate(Context context, int resource, ViewGroup root) 
        showInMiddle = (LinearLayout) (context, .il_hall,
                null);
        // root 不为null, 返回root
        // root 为null,不会setLayoutParams,导致 () 返回 null, 
        //解决办法是手动设置一下,(但ListView比较特殊,它自己设置好了)
        if (() == null) {
            (new (
                    LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
        }
    }

ListView中的源码:

   private void measureScrapChild(View child, int position, int widthMeasureSpec) {
        LayoutParams p = (LayoutParams) ();
        **if (p == null) {
            p = () generateDefaultLayoutParams();
            (p);
        }**
        ..............
    }    
   /**
     * Measure a particular list child.
     * TODO: unify with setUpChild.
     * @param child The child.
     */
    private void measureItem(View child) {
         p = ();
        **if (p == null) {
            p = new (
                    .MATCH_PARENT,
                    .WRAP_CONTENT);
        }**
        ..............
      }