fragment 调用activity方法，如dispatchKeyEvent，dispatchTouchEvent

以dispatchKeyEvent为例

1、创建回调接口FragmentKeyeventListener

/**
 * 作者：created by meixi
 * 邮箱：[email protected]
 * 日期：2018/9/10 15
 */
public interface FragmentKeyeventListener {
    boolean onFragmentKeyEvent(KeyEvent event);
}

2、fragment实现接口

public class TestFragment extends Fragment implements FragmentKeyeventListener{

TestActivity testActivity ;

@Override

public void onAttach(Activity activity) {

super.onAttach(activity); testActivity = (TestActivity)activity;

testActivity.setFragmentKeyeventListener(this); //设置监听

}

@Override

public boolean onFragmentKeyEvent(KeyEvent event) {//实现回调方法

return false;

}

}

3、activity代码，通过接口把dispatchKeyEvent事件传递到fragment

 

FragmentKeyeventListener fragmentKeyeventListener;

public void setFragmentKeyeventListener(FragmentKeyeventListener fragmentKeyeventListener) {
    this.fragmentKeyeventListener = fragmentKeyeventListener;
}

@Override
public boolean dispatchKeyEvent(KeyEvent event) {
    //防止该方法执行两次
    if(event.getKeyCode() == KeyEvent.KEYCODE_BACK && event.getAction() != KeyEvent.ACTION_UP) {//不响应按键抬起时的动作
        return false
    }
    if (fragmentKeyeventListener!=null&&event.getKeyCode()==66){
        fragmentKeyeventListener.onFragmentKeyEvent(event);
        return true;
    }
    return super.dispatchKeyEvent(event);
}