Java 如何从主要活动调用片段方法
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How to call fragment method from main activity
提问by hikoo
I have method in fragment class. I want to call that method from main activity but I don't want to use FragmentById (or) FragmentByTag.
我在片段类中有方法。我想从主要活动中调用该方法，但我不想使用 FragmentById（或）FragmentByTag。
My fragment method:
我的片段方法：
public void setItemFromDrawer(String sourceTag, String destTag) {
//dosomething
}
How to call above method from main activity without using FragmentById (or) FragmentByTag?
如何在不使用 FragmentById（或）FragmentByTag 的情况下从主活动调用上述方法？
回答by Khizar Hayat
In Activity use something like this where you load your fragment:
在 Activity 中使用类似这样的东西来加载你的片段：
FragmentTransaction transaction = getSupportFragmentManager().beginTransaction();
transaction.replace(container, fragment);
transaction.addToBackStack(null); // if you want to store transaction
transaction.commit();
currentFragment = fragment; // currentFragment is global Fragment variable
Use following line where you want to call fragment's method
在要调用片段方法的地方使用以下行
currentFragment.setItemFromDrawer("sourceTag","destTag");
回答by Farhad Faghihi
First create an interface
首先创建一个接口
public interface MyInterface
{
void myAction() ;
}
Your fragment must implement this interface.
您的片段必须实现此接口。
public MyFragment extends Fragment implements MyInterface
In your activity, define a field of type MyInterface:
在您的活动中，定义一个 MyInterface 类型的字段：
private MyInterface listener ;
public void setListener(MyInterface listener)
{
this.listener = listener ;
}
When creating your fragment and adding it :
创建片段并添加它时：
setListener(myFragment);
Finally, when the condtion happens that you want to call the Fragment method, just call :
最后，当您想调用 Fragment 方法时，只需调用：
listener.myAction() ; // this will call the implementation in your MyFragment class.
回答by user5466222
((YourFragment Class) fragment).Your method();
((YourFragment Class) 片段)。你的方法();
its worked form me
它的工作形式我
回答by user5466222
it means your calling a fragment method
这意味着你调用了一个片段方法
((YourFragmentClass) fragment).Yourmethod();
回答by Sif
To better explain the answer by user5466222:
为了更好地解释user5466222的答案：
YourFragmentClass fragment = new YourFragmentClass();
((YourFragmentClass) fragment).yourmethod();
