我试图在一个片段中创建一个ImageView，它将引用我在XML中为片段创建的ImageView元素。但是，findViewById方法仅在扩展Activity类时有效。我是否也可以在Fragment中使用它?
public class TestClass extends Fragment {
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
ImageView imageView = (ImageView)findViewById(R.id.my_image);
return inflater.inflate(R.layout.testclassfragment, container, false);
}
}
findViewById方法有一个错误，说明该方法未定义。
当前回答
使用gradle skeleton插件，它会自动生成视图持有者类，并引用到你的布局。
public class TestClass extends Fragment {
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
MyLayout myLayout = new MyLayout(inflater, container, false);
myLayout.myImage.setImageResource(R.drawable.myImage);
return myLayout.view;
}
}
现在假设你在my_layout.xml文件中声明了一个ImageView，它会自动为你生成myLayout类。
其他回答
getView()只在onCreateView()完成后工作，所以从onPostCreate()调用它:
@Override
public void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
ImageView imageView = (ImageView) getView().findViewById(R.id.foo);
}
根据API级别11的文档
参考，在Back Stack http://developer.android.com/reference/android/app/Fragment.html
短代码
/**
* The Fragment's UI is just a simple text view showing its
* instance number.
*/
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.hello_world, container, false);
View tv = v.findViewById(R.id.text);
((TextView)tv).setText("Fragment #" + mNum);
tv.setBackgroundDrawable(getResources().getDrawable(android.R.drawable.gallery_thumb));
return v;
}
//here you can do it by
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState)
{
// Inflate the layout for this fragment
final View view = inflater.inflate(R.layout.fragment_apple, container,
false);
ist = view.findViewById(R.id.linearLink);
second = view.findViewById(R.id.linearPhone);
return view;
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.testclassfragment, container, false);
ImageView imageView = (ImageView) view.findViewById(R.id.my_image);
return view;
}
注意，如果你使用getView()方法，它可能会导致nullPointerException，因为它返回根视图，它将是onCreateView()方法之后的某个视图。
在Fragment类中，我们得到onViewCreated()重写方法，我们应该总是初始化我们的视图，因为在这个方法中我们得到视图对象。使用这个对象，我们可以像下面这样找到我们的视图:
class MyFragment extends Fragment {
private ImageView imageView;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.my_fragment_layout, container, false);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
//initialize your view here for use view.findViewById("your view id")
imageView = (ImageView) view.findViewById(R.id.my_image);
}
}
