android - 将BottomSheetDialogFragment的状态设置为展开

如何使用Android支持设计库(v23.2.1)设置将BottomSheetDialogFragment扩展为使用BottomSheetBehavior#setState(STATE_EXPANDED)扩展的片段的状态？

https://code.google.com/p/android/issues/detail?id=202396说:



suggested practice需要首先放大 View ，但是我不确定如何将BottomSheetBehaviour设置到片段(BottomSheetDialogFragment)上。

View bottomSheet = coordinatorLayout.findViewById(R.id.bottom_sheet);
BottomSheetBehavior behavior = BottomSheetBehavior.from(bottomSheet);

最佳答案

以上是线索。

对话框的显示为时，将触发对话框。如果未布置对话框，则无法显示。

因此，在模态底部工作表的onCreateDialog()(BottomSheetFragment)中，就在返回对话框之前(或者在引用对话框之后，在​​任何位置)调用:

// This listener's onShow is fired when the dialog is shown
dialog.setOnShowListener(new DialogInterface.OnShowListener() {
    @Override
    public void onShow(DialogInterface dialog) {

        // In a previous life I used this method to get handles to the positive and negative buttons
        // of a dialog in order to change their Typeface. Good ol' days.

        BottomSheetDialog d = (BottomSheetDialog) dialog;

        // This is gotten directly from the source of BottomSheetDialog
        // in the wrapInBottomSheet() method
        FrameLayout bottomSheet = (FrameLayout) d.findViewById(android.support.design.R.id.design_bottom_sheet);

        // Right here!
        BottomSheetBehavior.from(bottomSheet)
            .setState(BottomSheetBehavior.STATE_EXPANDED);
    }
});

就我而言，我的自定义BottomSheet原来是:

@SuppressWarnings("ConstantConditions")
public class ShareBottomSheetFragment extends AppCompatDialogFragment {

    @NonNull @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        BottomSheetDialog dialog =
                new BottomSheetDialog(getActivity(), R.style.Haute_Dialog_ShareImage);

        dialog.setContentView(R.layout.dialog_share_image);

        dialog.findViewById(R.id.cancel).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                dismiss();
            }
        });

        dialog.setOnShowListener(new DialogInterface.OnShowListener() {
            @Override
            public void onShow(DialogInterface dialog) {
                BottomSheetDialog d = (BottomSheetDialog) dialog;

                FrameLayout bottomSheet = (FrameLayout) d.findViewById(android.support.design.R.id.design_bottom_sheet);
                BottomSheetBehavior.from(bottomSheet).setState(BottomSheetBehavior.STATE_EXPANDED);
            }
        });

        SwitchCompat switchview = (SwitchCompat) dialog.findViewById(R.id.switchview);
        switchview.setTypeface(FontCache.get(dialog.getContext(), lookup(muli, NORMAL)));

        return dialog;
    }
}

让我知道是否有帮助。

更新

请注意，您还可以将BottomSheetDialogFragment覆盖为:

public class SimpleInitiallyExpandedBottomSheetFragment extends BottomSheetDialogFragment {

    @NonNull @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {

        BottomSheetDialog dialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState);

        dialog.setOnShowListener(new DialogInterface.OnShowListener() {
            @Override
            public void onShow(DialogInterface dialog) {
                BottomSheetDialog d = (BottomSheetDialog) dialog;

                FrameLayout bottomSheet = (FrameLayout) d.findViewById(android.support.design.R.id.design_bottom_sheet);
                BottomSheetBehavior.from(bottomSheet).setState(BottomSheetBehavior.STATE_EXPANDED);
            }
        });

        // Do something with your dialog like setContentView() or whatever
        return dialog;
    }
}

但是我真的不明白为什么有人会这样做，因为基本BottomSheetFragment除了返回BottomSheetDialog之外什么都不做。

更新ANDROIDX

使用AndroidX时，现在可以在android.support.design.R.id.design_bottom_sheet上找到以前在com.google.android.material.R.id.design_bottom_sheet上找到的资源。