Question

我想在我的ScrollView中添加多个LinearLayout，LinearLayout的数量取决于从MySQL数据库中选择的数据量。但是，似乎不能在ScrollView中添加多个LinearLayout。

原因可能是这样的：指定的孩子已经有一个父母。您必须先在孩子的父母上调用removeView（）。但是我不确定真正的原因。我怎么解决这个问题？这是我在Android Studio中的编码：

String query = "select * from restaurant";
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(query);

LinearLayout data_big_layout, detail_data_layout;
TextView name, type_area, price_txt;
ImageView restaurant_img;
LinearLayout.LayoutParams restaurant_img_params, data_big_params;

while(rs.next()){
    data_big_layout = new LinearLayout(this);
    data_big_params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
    LinearLayout.LayoutParams.WRAP_CONTENT);
    data_big_params.setMargins(0,15,0,0);
    data_big_layout.setLayoutParams(data_big_params);
    data_big_layout.setOrientation(LinearLayout.HORIZONTAL);
    data_big_layout.setWeightSum(20);
    data_big_layout.setBackgroundColor(Color.WHITE);
    data_big_layout.setTag(rs.getInt(1));

    detail_data_layout = new LinearLayout(this);
    lparams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
    LinearLayout.LayoutParams.WRAP_CONTENT,8.0f);
    detail_data_layout.setLayoutParams(lparams);
    detail_data_layout.setOrientation(LinearLayout.VERTICAL);
    detail_data_layout.setPadding(50,0,0,0);

    lparams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
    LinearLayout.LayoutParams.WRAP_CONTENT);
    name = new TextView(this);
    name.setLayoutParams(lparams);
    name.setText(rs.getString(2));
    name.setTextSize(24);
    name.setTypeface(Typeface.DEFAULT_BOLD);

    type_area = new TextView(this);
    type_area.setLayoutParams(lparams);
    type_area.setText(rs.getString(5)+"/"+rs.getString(6));
    type_area.setTextSize(18);

    price_txt = new TextView(this);
    price_txt.setLayoutParams(lparams);
    price_txt.setText(rs.getString(7));
    price_txt.setTextSize(18);

    detail_data_layout.addView(name);
    detail_data_layout.addView(type_area);
    detail_data_layout.addView(price_txt);

    data_big_layout.addView(detail_data_layout);

    restaurant_img = new ImageView(this);
    restaurant_img_params = new LinearLayout.LayoutParams(200,
    300,12.0f);
    restaurant_img.setImageResource(R.drawable.test_restaurant);
    restaurant_img.setPadding(0,0,50,0);

    data_big_layout.addView(restaurant_img, restaurant_img_params);
    Toast.makeText(getBaseContext(),"ID: "+rs.getInt(1), Toast.LENGTH_LONG).show();

    data_scroll_view.addView(data_big_layout); //Cannot add data_big_layout in the next loop

    z = "Search successful";

}
isSuccess = true;
stmt.close();
rs.close();
con.close();

代码 data_scroll_view.addView（data_big_layout）; 仅可在while循环的第一次运行。我选择了两行数据，但是程序中的输出只能显示一个LinearLayout。我该如何解决？谢谢大家。

Answer 1

滚动视图只能包含一个孩子

滚动视图中只能放置一个直接子级。 Google doc

因此，在循环内，应将视图收集到单个垂直LinearLayout中，然后将其添加到循环外的ScrollView中。

Answer 2

引用https://developer.android.com/reference/android/widget/ScrollView

ScrollView是“允许放置视图层次结构的视图组在其中滚动。滚动视图可能只有一个直接子级放在里面。

要在滚动视图中添加多个视图，请使直接子级添加一个视图组，例如LinearLayout，然后在该LinearLayout“内放置其他视图。

因此，与其尝试将LinearLayouts添加到ScrollView中，不如将一个LinearLayout作为ScrollView's的子元素，并向该LinearLayout添加任何视图/布局

使用while循环在滚动视图中添加多个LinearLayout

2 个答案: