Question

当我调用片段时，我试图模糊背景，但是它没有用。我使用set alpha但我的应用程序崩溃了

public class IDs{

    public string someID{ get; set; }

    public IDs(string someId){
        this.someID = someId;
        log.info(this.someID);
           //use someID here
    }
}

pulic class otherClass{


     public otherMethod(string sym){
                IDs id = new IDs(sym);
            }
      }

public class anotherClass{

                //access instance of otherClass in wrp and call otherMethod()
               wrp.otherMethod("someStringSymbol")
         }

Answer 1

当您必须从“视图” /“ Xml”中访问任何元素时。您可以做以下事情来访问它。

在 onCreateView 中：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup parent, Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment_layout, parent, false); // This will take you're Fragment layout.
    ListView listView = (ListView )rootView.findViewById(R.id./*Id of listview*/);
    //Then you can access the things you want to do
    listView.getBackground().setAlpha(200); //Something like this Here you're listview is assigned
    return rootView;
}

尝试在空对象引用上调用虚拟方法'void android.graphics.drawable.Drawable.setAlpha（int）'

1 个答案: