如何从父活动以编程方式更改片段视图

Question

我有一个包含例如一个按钮的片段，我想允许包含该片段的活动更改此按钮视图，例如颜色和标题或src图像。最好的方法是什么？

更新：如果我不够清楚，很抱歉，但我希望活动可以随心所欲地更改整个视图，比如设置填充、颜色或任何东西。它将以编程方式创建视图，片段应该用新视图替换旧视图，并更改视图的ID，以便片段代码不受影响。如果我在片段中创建了获取这些视图的方法，那么主活动应该在什么时候调用它们？因为活动必须等待创建片段的布局。

Answer 1

根据您的要求尝试这种方式

public abstract class BaseFragment extends Fragment {
    BaseActivity yourActivity;
    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

   @Override
   public void onAttach(Context context) {
       super.onAttach(context);
      yourActivity = (BaseActivity) context;
   }

   @Override
   public void onDetach() {
       yourActivity = null;
       super.onDetach();
    }


    public void refreshview(){} 

    public void setDada(Data data){}


    @override
    publicn void onStart(){
        yourActivity.setCurrentOpenedFragment(this);
    }
}

创建BaseActivity类

public abstract class BaseActivity extends AppCompatActivity{
   @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }
     public void setCurrentOpenedFragment(BaseFragment currentFragment){}
}

扩展您的片段中的Base片段，即。

public class YourFragment extends BaseFragment{
   View view;       
   Button button;
   @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {       
          view = inflater.inflate(R.layout.fragment, container, false);
          button = (Button)view.findViewById(R.id.button);
          return view;
    }

    @override
    publicn void onStart(){
      super.onStart();
      //yourActivity.setCurrentOpenedFragment(this);
   }

   Data data; 
   @override 
   public void setDada(Data data){
     this.data = data;
   } 
    @Override 
    public void refreshview() {
       button.setcolor(data.getcolor());
    }
} 

在活动类中编写以下代码行

public class YourActivity extends BaseActivity{

   public static final byte NONE =  -1;
   public static final byte HOME =  1;

   @Override
    protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
            setContentView(R.layout.your_activity);
            changeFragment(new YourFragment(), HOME);
            initview();
    }

   public void initview(){
        Button b = (Button)findViewById(R.id.button);
        b.setOnClickListener(new OnClickListener(){
          if(currentFragmentOnDrawer != null){

            Data data = new Data();
            data.setColor(getResource().getcolor(R.color.red));
            currentFragmentOnDrawer.setDada(data);

            currentFragmentOnDrawer.refreshview()

         }
       });
   }

   BaseFragment currentFragmentOnDrawer;
    @Override
    public void setCurrentOpenedFragment(BaseFragment currentFragment) {
        super.setCurrentOpenedFragment(currentFragment);
        this.currentFragmentOnDrawer = currentFragment;
    }

   public void changeFragment(Fragment targetFragment, byte state) {

      FragmentTransaction ft = getSupportFragmentManager()
            .beginTransaction();
      ft.replace(R.id.main_fragment, targetFragment, "" + state);
      ft.addToBackStack("" + state);
      ft.commit();
  }
}

希望对你有帮助

Answer 2

1.你必须从你的活动中获得碎片

val fragment = supportFragmentManager.findFragmentByTag("tag")

或

val fragment = supportFragmentManager.findFragmentById(R.id.fragment)

2

fragment.hideButton()

或者您可以使用界面