如何制作具有底部重力和 alpha 背景的警报对话框？

Question

我正在使用警报对话框在 android 应用程序中创建一个对话框。我有一个问题。它的背景是全白的。我想要对话框 window 的背景具有 alpha（半透明），如图所示。请帮我。

View layoutView = activity.getLayoutInflater().inflate(R.layout.alert_dialog_image, null);
    AlertDialog.Builder builder = new AlertDialog.Builder(activity, R.style.DialogTheme);
    builder.setView(layoutView);
    final AlertDialog alertDialog = builder.create();
    alertDialog.show();

Answer 1

您可以通过两种方式实现这一目标。

1. BottomSheetDialog https://developer.android.com/reference/com/google/android/material/bottomsheet/BottomSheetDialog
2. BottomSheetDialogFragment https://developer.android.com/reference/com/google/android/material/bottomsheet/BottomSheetDialogFragment

例如fragment_bottom_sheet_dialog.xml

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/lorem_ipsum"/>

    </LinearLayout>

BottomSheetFragment.java

public class BottomSheetFragment extends BottomSheetDialogFragment {
    public BottomSheetFragment() {
        // Required empty public constructor
    }
 
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }
 
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
        return inflater.inflate(R.layout.fragment_bottom_sheet_dialog, container, false);
    }
}

现在在activity/fragment里面，可以根据点击事件等任何事件调用这两个方法

public void showBottomSheetDialog() {
    View view = getLayoutInflater().inflate(R.layout.fragment_bottom_sheet_dialog, null);
 
    BottomSheetDialog dialog = new BottomSheetDialog(this);
    dialog.setContentView(view);
    dialog.show();
}
 
 
/**
 * showing bottom sheet dialog fragment
 * same layout is used in both dialog and dialog fragment
 */

public void showBottomSheetDialogFragment() {
    BottomSheetFragment bottomSheetFragment = new BottomSheetFragment();
    bottomSheetFragment.show(getSupportFragmentManager(), bottomSheetFragment.getTag());
}