Android中給BottomSheetDialog設置最大高度(含沉浸式)

BottomSheetDialog沒有提供設置最大高度的Api，所以需要我們自己手動去改變最大高度，我這裏通過繼承BottomSheetDialog重寫oncreate()來實現。
我這裏用的是最新的androidx，需要導入Material Components

dependencies{
  ...
  implementation group: 'com.google.android.material', name: 'material', version: '1.2.0-alpha02'
  ...
}

下面是重寫後完整的類。

package com.example.myapplication;

import android.content.Context;
import android.graphics.Point;
import android.os.Bundle;
import android.view.Gravity;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;
import com.google.android.material.bottomsheet.BottomSheetDialog;


import androidx.annotation.NonNull;

public class MyBottomSheetDialog extends BottomSheetDialog {
    public MyBottomSheetDialog(@NonNull Context context) {
        super(context);
    }

    public MyBottomSheetDialog(@NonNull Context context, int theme) {
        super(context, theme);
    }

    protected MyBottomSheetDialog(@NonNull Context context, boolean cancelable, OnCancelListener cancelListener) {
        super(context, cancelable, cancelListener);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        final int screenHeight = getScreenHeight(getContext());
        int dialogHeight;
        if (screenHeight == 0) {
            dialogHeight = screenHeight;
        } else {
            dialogHeight = ViewGroup.LayoutParams.MATCH_PARENT;
        }
        
        Window window = getWindow();
        assert window != null;
        
        //設置成沉浸式
        window.setLayout(ViewGroup.LayoutParams.MATCH_PARENT, dialogHeight);
        
        //需要設置最大高度
        //你想要減去的高度，dialog默認最大高度在狀態欄下方
        //float reduceHeight = getContext().getResources().getDimension(R.dimen.xxx); 
        //window.setLayout(ViewGroup.LayoutParams.MATCH_PARENT,dialogHeight - reduceHeight);
        //最後一步是必須的，否則BottomSheetDialog會顯示在屏幕中間，底部會出現空白區域
        //window.setGravity(Gravity.BOTTOM);
    }

	/**
     * 獲取屏幕的高度
     * @param context
     * @return
     */
    public static int getScreenHeight(Context context) {
        WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
        Point point = new Point();
        assert wm != null;
        wm.getDefaultDisplay().getSize(point);
        return point.y;
    }
    
}