Question

我正在尝试将checkbox添加到fragment，如下所示：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/addProductButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:text="Add Product" />


</LinearLayout>

然后我创建checkBox并尝试将其添加到fragment

   @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_product_list, container, false);

            LinearLayout ll = new LinearLayout(getActivity());
            ll.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
            ll.setOrientation(LinearLayout.VERTICAL);
            for (int i = 0; i < 20; i++) {
                CheckBox cb = new CheckBox(rootView.getContext());
                ll.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
                cb.setText("check");
                ll.addView(cb);
            }
            return rootView;
        }
    }

但是复选框不可见。

enter image description here

Answer 1

你不能添加相同的CheckBox实例20次。您需要在每次迭代时创建一个新的。移动

在for循环中

for (int i = 0; i < 20; i++) {
     CheckBox cb = new CheckBox(rootView.getContext());
     ll.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
     cb.setText("check");
     ll.addView(cb);
}

Answer 2

为你的linearLayout添加一个id，如：

 android:id="@+id/linearLayout"

然后在你的代码中你有：

 LinearLayout ll = rootView.findViewById(R.id.linearLayout);
 // other code

另一种必须工作的方法是创建一个布局并添加视图，并将此linearLayout添加到该

Answer 3

更改此类onCreateView()方法..不需要findViewById()或其他任何

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    LinearLayout rootView = (LinearLayout) inflater.inflate(
            R.layout.fragment_product_list, container, false);

    // LinearLayout ll = new LinearLayout(getActivity());
    rootView.setOrientation(LinearLayout.VERTICAL);
    for (int i = 0; i < 20; i++) {
        CheckBox cb = new CheckBox(rootView.getContext());
        rootView.setLayoutParams(new LayoutParams(
                LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
        cb.setText("check");
        rootView.addView(cb);
    }
    return rootView;
}

动态向片段添加复选框 - 复选框不可见

3 个答案: