这个问题的原因是

item的布局没有设置具体宽高,先指定宽高,如果还要再计算宽高可以在onbindView中再计算设置

ImageView img1 =  holder.findViewById(R.id.img1);
                LinearLayout content= holder.findViewById(R.id.content);
                int width=  ((ScreenUtils.getScreenWidth(SuggestionActivity.this)-ScreenUtils.dip2px(SuggestionActivity.this,50))/4);
                LinearLayout.LayoutParams layoutParams= new LinearLayout.LayoutParams(width,width);
                img1.setLayoutParams(layoutParams);
                content.setLayoutParams(layoutParams);

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:layout_width="match_parent"
              android:gravity="center"
              android:layout_height="wrap_content"
              android:id="@+id/content"
              android:orientation="vertical">

    <ImageView
            android:id="@+id/img1"
            android:layout_width="60dp"
            android:layout_height="60dp"
    />


</LinearLayout>