在片段多個按鍵不靈

Question

試圖讓我的按鈕全部3片段使用相同的單擊事件後Click事件，public class FragmentShapesDemo extends android.support.v4.app.Fragment implements View.OnClickListener變成紅色下劃線&返回錯誤：

Class 'FragmentShapesDemo' must either be declared abstract or implement abstract method 'onClick(View)' in OnClickListener

我不不懂爲什麼這個錯誤出現時，點擊事件已實施： -/

fragment_shapes_demo.xml

<Button 
    android:id="@+id/btn_1" 
    android:onClick="btn_Click" 
    android:text="@string/circles"/> 

<Button 
    android:id="@+id/btn_2" 
    android:onClick="btn_Click" 
    android:text="@string/squares"/> 

<Button 
    android:id="@+id/btn_3" 
    android:onClick="btn_Click" 
    android:text="@string/triangles"/> 

FragmentShapesDemo.java

public class FragmentShapesDemo extends android.support.v4.app.Fragment { 

    Button button0; 
    Button button1; 
    Button button2; 

    public FragmentShapesDemo() { 
     // Required empty constructor 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 

     View v = inflater.inflate(R.layout.fragment_shapes_demo, container, false); 

     button0 = (Button) v.findViewById(R.id.btn_1); 
     button1 = (Button) v.findViewById(R.id.btn_2); 
     button2 = (Button) v.findViewById(R.id.btn_3); 

     button0.setOnClickListener(this); 
     button1.setOnClickListener(this); 
     button2.setOnClickListener(this); 

     return v; 
    } 

    public void btn_Click(View v) { 
     Toast.makeText(getActivity(), "Hello World", Toast.LENGTH_LONG).show();  
    } 
} 

Answer 1

從XML刪除onClick：

<Button 
    android:id="@+id/btn_1" 

    android:text="@string/circles"/> 

<Button 
    android:id="@+id/btn_2" 
    android:text="@string/squares"/> 

<Button 
    android:id="@+id/btn_3" 
    android:text="@string/triangles"/> 

使用您的rootView參考找到要點的意見。你爲什麼要使用getActivity（）

public class FragmentShapesDemo extends android.support.v4.app.Fragment { 

    Button button0; 
    Button button1; 
    Button button2; 

    public FragmentShapesDemo() { 
     // Required empty constructor 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { 

     View v = inflater.inflate(R.layout.fragment_shapes_demo, container, false); 

     button0 = (Button)v.findViewById(R.id.btn_1); 
     button1 = (Button)v.findViewById(R.id.btn_2); 
     button2 = (Button)v.findViewById(R.id.btn_3); 

     button0.setOnClickListener(new OnClickListener() { 
       public void onClick(View v) { 
        Toast.makeText(getActivity, "Do Your Work", Toast.LENGTH_SHORT).show(); 
       } 
      }); 

     button1.setOnClickListener(new OnClickListener() { 
       public void onClick(View v) { 

       } 
      }); 

     button2.setOnClickListener(new OnClickListener() { 
       public void onClick(View v) { 

       } 
      }); 

     return v; 
    } 
}