原生控件仿苹果底部抽屉弹框

demo地址：https://github.com/feiyuu/BottomSheetDialogDemo

基本使用很简单：

public class FullSheetDialogFragment extends BottomSheetDialogFragment {
    private BottomSheetBehavior mBehavior;
    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
        BottomSheetDialog dialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState);
        View view = View.inflate(getContext(), R.layout.dialog_bottom_sheet, null);
        dialog.setContentView(view);
        mBehavior = BottomSheetBehavior.from((View) view.getParent());
        return dialog;
    }
 
    @Override
    public void onStart()
    {
        super.onStart();
        //默认全屏展开
        mBehavior.setState(BottomSheetBehavior.STATE_EXPANDED);
    }
 
    public void doclick(View v)
    {
        //点击任意布局关闭
        mBehavior.setState(BottomSheetBehavior.STATE_HIDDEN);
    }
}

调用BottomSheetDialogFragment展示

new FullSheetDialogFragment().show(getSupportFragmentManager(), "dialog");

下面是一些坑。

dialog按屏幕高度百分比调整大小：

BottomSheetDialog dialog = (BottomSheetDialog) super.onCreateDialog(savedInstanceState); mContext = getContext(); 
View view = View.inflate(mContext, R.layout.dialog_bottom_sheet1, null); dialog.setContentView(view); 
ViewGroup.LayoutParams layoutParams = view.getLayoutParams(); 
int height = (int) (mContext.getResources().getDisplayMetrics().heightPixels * 0.9); layoutParams.height = height; 
view.setLayoutParams(layoutParams);
 

去除层叠显示（就是去掉完全展开，中间状态，隐藏中的中间状态）：

height就是整个dialog的高度，同上面的height。如果设置为0也可以实现效果，但会导致滑动关闭后，有一层阴影遮罩，
需要点击一次才能消失。原因是设置为0，滑动到看不见时，其实是处于中间状态，并没有完全关闭dialog。

mBehavior.setPeekHeight(height);

圆角背景：

//先设置背景为透明
 
dialog.getWindow().findViewById(R.id.design_bottom_sheet).setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
 
//shape
 
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle"
    >
 
    <corners
        android:topLeftRadius="20dp"
        android:topRightRadius="20dp"></corners>
    <solid android:color="@color/white"></solid>
 
</shape>