android - DialogFragment 和 onDismiss

Question

我正在使用 DialogFragment，我在 Activity 中显示如下:

DialogFragmentImage dialog = DialogFragmentImage.newInstance(createBitmap());
dialog.onDismiss(dialog);.onDismiss(this);          
dialog.show(getFragmentManager(), "DialogFragmentImage");

我想检查 DialogFragment 何时被解除(例如，当按下后退按钮时)，但在我的 Activity 中。我怎样才能做到这一点？如何“告诉”我的 activity DialogFragment 已被解除？

Answer 1

让你的Activity实现OnDismissListener

public final class YourActivity extends Activity implements DialogInterface.OnDismissListener {

    @Override
    public void onDismiss(final DialogInterface dialog) {
        //Fragment dialog had been dismissed
    }

}

DialogFragment已经实现了OnDismissListener，只需重写方法调用Activity即可。

public final class DialogFragmentImage extends DialogFragment {

    ///blah blah

    @Override
    public void onDismiss(final DialogInterface dialog) {
        super.onDismiss(dialog);
        final Activity activity = getActivity();
        if (activity instanceof DialogInterface.OnDismissListener) {
            ((DialogInterface.OnDismissListener) activity).onDismiss(dialog);
        }
    }

}

如果您使用 childFragment 管理器 (API>=17) 从 fragment 启动对话框，则可以使用 getParentFragment 与父级上的 onDismissListener 对话 fragment :

public final class DialogFragmentImage extends DialogFragment {

    ///blah blah

    @Override
    public void onDismiss(final DialogInterface dialog) {
        super.onDismiss(dialog);
        Fragment parentFragment = getParentFragment();
        if (parentFragment instanceof DialogInterface.OnDismissListener) {
            ((DialogInterface.OnDismissListener) parentFragment).onDismiss(dialog);
        } 
    }

}