Android multi-level pop-up window implementation

I went to a company for an interview yesterday and asked to implement a pop-up window and implement a multi-selection function. The effect is similar to Jingdong's multi-level screening. The effect is as follows:

The idea of ​​​​the implementation is relatively simple. PopupWindow is used to display pop-up windows. PopupWindow is mainly composed of lists, and specific sub-items can be implemented using GridView. The custom flow layout I use here, the layout of custom FlowLayout code show as below:

public class FlowLayout extends ViewGroup {

    private static final int LEFT = -1;
    private static final int CENTER = 0;
    private static final int RIGHT = 1;

    protected List<List<View>> mAllViews = new ArrayList<>();
    protected List<Integer> mLineHeight = new ArrayList<>();
    protected List<Integer> mLineWidth = new ArrayList<>();
    private int mGravity;
    private List<View> lineViews = new ArrayList<>();

    public FlowLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public FlowLayout(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public FlowLayout(Context context) {
        this(context, null);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int sizeWidth = MeasureSpec.getSize(widthMeasureSpec);
        int modeWidth = MeasureSpec.getMode(widthMeasureSpec);
        int sizeHeight = MeasureSpec.getSize(heightMeasureSpec);
        int modeHeight = MeasureSpec.getMode(heightMeasureSpec);

        int width = 0;
        int height = 0;

        int lineWidth = 0;
        int lineHeight = 0;

        int cCount = getChildCount();

        for (int i = 0; i < cCount; i++) {
            View child = getChildAt(i);
            if (child.getVisibility() == View.GONE) {
                if (i == cCount - 1) {
                    width = Math.max(lineWidth, width);
                    height += lineHeight;
                }
                continue;
            }
            measureChild(child, widthMeasureSpec, heightMeasureSpec);
            MarginLayoutParams lp = (MarginLayoutParams) child
                    .getLayoutParams();
            lp.leftMargin = 10;
            lp.rightMargin = 10;
            lp.topMargin = 10;
            lp.bottomMargin = 10;

            int childWidth = child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;
            int childHeight = child.getMeasuredHeight() + lp.topMargin + lp.bottomMargin;

            if (lineWidth + childWidth > sizeWidth - getPaddingLeft() - getPaddingRight()) {
                width = Math.max(width, lineWidth);
                lineWidth = childWidth;
                height += lineHeight;
                lineHeight = childHeight;
            } else {
                lineWidth += childWidth;
                lineHeight = Math.max(lineHeight, childHeight);
            }
            if (i == cCount - 1) {
                width = Math.max(lineWidth, width);
                height += lineHeight;
            }
        }
        setMeasuredDimension(
                modeWidth == MeasureSpec.EXACTLY ? sizeWidth : width + getPaddingLeft() + getPaddingRight(),
                modeHeight == MeasureSpec.EXACTLY ? sizeHeight : height + getPaddingTop() + getPaddingBottom()//
        );

    }


    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        mAllViews.clear();
        mLineHeight.clear();
        mLineWidth.clear();
        lineViews.clear();

        int width = getWidth();

        int lineWidth = 0;
        int lineHeight = 0;

        int cCount = getChildCount();

        for (int i = 0; i < cCount; i++) {
            View child = getChildAt(i);
            if (child.getVisibility() == View.GONE) continue;
            MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();

            int childWidth = child.getMeasuredWidth();
            int childHeight = child.getMeasuredHeight();

            if (childWidth + lineWidth + lp.leftMargin + lp.rightMargin > width - getPaddingLeft() - getPaddingRight()) {
                mLineHeight.add(lineHeight);
                mAllViews.add(lineViews);
                mLineWidth.add(lineWidth);

                lineWidth = 0;
                lineHeight = childHeight + lp.topMargin + lp.bottomMargin;
                lineViews = new ArrayList<>();
            }
            lineWidth += childWidth + lp.leftMargin + lp.rightMargin;
            lineHeight = Math.max(lineHeight, childHeight + lp.topMargin + lp.bottomMargin);
            lineViews.add(child);

        }
        mLineHeight.add(lineHeight);
        mLineWidth.add(lineWidth);
        mAllViews.add(lineViews);


        int left = getPaddingLeft();
        int top = getPaddingTop();

        int lineNum = mAllViews.size();

        for (int i = 0; i < lineNum; i++) {
            lineViews = mAllViews.get(i);
            lineHeight = mLineHeight.get(i);

            int currentLineWidth = this.mLineWidth.get(i);
            switch (this.mGravity) {
                case LEFT:
                    left = getPaddingLeft();
                    break;
                case CENTER:
                    left = getPaddingLeft();
                    break;
                case RIGHT:
                    left = width - currentLineWidth + getPaddingLeft();
                    break;
            }

            for (int j = 0; j < lineViews.size(); j++) {
                View child = lineViews.get(j);
                if (child.getVisibility() == View.GONE) {
                    continue;
                }

                MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();

                int lc = left + lp.leftMargin;
                int tc = top + lp.topMargin;
                int rc = lc + child.getMeasuredWidth();
                int bc = tc + child.getMeasuredHeight();

                child.layout(lc, tc, rc, bc);

                left += child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;
            }
            top += lineHeight;
        }

    }

    @Override
    public LayoutParams generateLayoutParams(AttributeSet attrs) {
        return new MarginLayoutParams(getContext(), attrs);
    }

    @Override
    protected LayoutParams generateDefaultLayoutParams() {
        return new MarginLayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
    }

    @Override
    protected LayoutParams generateLayoutParams(LayoutParams p) {
        return new MarginLayoutParams(p);
    }
}

Then there is the specific code implementation. First, we build the structure of the data:

public class FilterBean {

    public String typeName;
    public List<Children> children;

    public static class Children {
        public String value;
        public int id;
        public boolean isSelected;
    }
}

Then there is the content of the Adapter.

public class PopListViewAdapter extends BasicAdapter<FilterBean>  {

    private Activity context;

    public PopListViewAdapter(Activity context) {
        this.context = context;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder viewHolder = null;
        if (convertView == null) {
            LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = layoutInflater.inflate(R.layout.item_popwindows, null);
            viewHolder = new ViewHolder(convertView);
        } else {
            viewHolder = (ViewHolder) convertView.getTag();
        }
        bindData(viewHolder, position);
        return convertView;
    }

    private void bindData(ViewHolder viewHolder, int position) {
        FilterBean bean = getItem(position);
        if (bean==null)return;
        viewHolder.tvTypeName.setText(bean.typeName);
        setFlowLayoutData(bean.children, viewHolder.itemFlowLayout);
    }

    private void setFlowLayoutData(final List<FilterBean.Children> childrenList, final FlowLayout flowLayout) {
        flowLayout.removeAllViews();
        for (int x = 0; x < childrenList.size(); x++) {
            CheckBox checkBox = (CheckBox) View.inflate(context, R.layout.item_checkbox, null);
            checkBox.setText(childrenList.get(x).value);
            //选中状态
            if (childrenList.get(x).isSelected) {
                checkBox.setChecked(true);
                childrenList.get(x).isSelected=true;
            } else {
                checkBox.setChecked(false);
                childrenList.get(x).isSelected=false;
            }

//            final int finalX = x;
//            checkBox.setOnClickListener(new View.OnClickListener() {
//                @Override
//                public void onClick(View v) {
//                    refreshCheckBox(flowLayout, finalX, childrenList);
//                }
//            });
            flowLayout.addView(checkBox);
        }
    }

    /**
     * 单选放开此代码
     */
    private void refreshCheckBox(FlowLayout flowLayout, int finalX, List<FilterBean.Children> propBeenList) {
        for (int y = 0; y < flowLayout.getChildCount(); y++) {
            CheckBox radio = (CheckBox) flowLayout.getChildAt(y);
            radio.setChecked(false);
            propBeenList.get(y).isSelected=false;
            if (finalX == y) {
                radio.setChecked(true);
                propBeenList.get(y).isSelected=true;
            }
        }
    }

    class ViewHolder {
        @BindView(R.id.tv_type_name)
        TextView tvTypeName;
        @BindView(R.id.item_flowLayout)
        FlowLayout itemFlowLayout;

        ViewHolder(View view) {
            ButterKnife.bind(this, view);
            view.setTag(this);
        }
    }
}

The corresponding layout is implemented using CheckBox, and the code is:

<?xml version="1.0" encoding="utf-8"?>
<CheckBox xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:background="@drawable/btn_selector"
    android:button="@null"
    android:gravity="center"
    android:paddingLeft="8dp"
    android:paddingRight="8dp"
    android:paddingTop="5dp"
    android:paddingBottom="5dp"
    android:textColor="@drawable/checkbox_text_color"
    android:textSize="13sp">

</CheckBox>

The code for the selector is as follows:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/btn_select" android:state_checked="true" />
    <item android:drawable="@drawable/btn_select" android:state_selected="true" />
    <item android:drawable="@drawable/btn_normal" />
</selector>

btn_select.xml

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#0079ff" />
    <corners android:radius="2dp" />
</shape>

btn_normal.xml

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <solid android:color="#dddddd" />
    <corners android:radius="2dp" />
</shape>

Then customize a PopupWindow

public class FilterPopWindow extends PopupWindow {


    @BindView(R.id.listView)
    MeasureListView listView;
    @BindView(R.id.tv_reset)
    TextView tvReset;
    @BindView(R.id.tv_confirm)
    TextView tvConfirm;
    @BindView(R.id.view_null)
    View viewNull;

    private final Activity context;
    private final List<FilterBean> dictList;
    private PopListViewAdapter adapter;
    private OnConfirmClickListener onConfirmClickListener;

    public FilterPopWindow(Activity context, List<FilterBean> dictList) {
        this.context = context;
        this.dictList = dictList;
        init();
    }

    private void init() {
        initPop();
        initView();
    }

    private void initPop() {
        View popView = View.inflate(context, R.layout.layout_filter_pop, null);
        ButterKnife.bind(this, popView);
        setContentView(popView);
        //LinearLayout.LayoutParams.MATCH_PARENT
        setWidth(-1);
        setHeight(-2);
        setFocusable(true);
        setOutsideTouchable(true);
        setBackgroundDrawable(new ColorDrawable(0x33000000));
    }

    private void initView() {
        tvReset.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                for (int x = 0; x < dictList.size(); x++) {
                    List<FilterBean.Children> childrenBeen = dictList.get(x).children;
                    for (int y = 0; y < childrenBeen.size(); y++) {
                        if (childrenBeen.get(y).isSelected)
                            childrenBeen.get(y).isSelected = false;
                    }
                }
                adapter.notifyDataSetChanged();
            }
        });
        tvConfirm.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                onConfirmClickListener.onConfirmClick();
                dismiss();
            }
        });
        viewNull.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                dismiss();
            }
        });
    }

    public void showAsDropDown(View view, int marginTop) {
        adapter = new PopListViewAdapter(context);
        listView.setAdapter(adapter);
        adapter.setList(dictList);
        showAsDropDown(view, 0, marginTop);
    }

    public void setOnConfirmClickListener(OnConfirmClickListener onConfirmClickListener) {
        this.onConfirmClickListener = onConfirmClickListener;
    }

    public interface OnConfirmClickListener {
        void onConfirmClick();
    }

}

The layout files involved in this class are:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">

    <View
        android:layout_width="match_parent"
        android:layout_height="1dp"
        android:background="@color/gray_f3" />

    <com.xzh.textureviewdemo.view.MeasureListView
        android:id="@+id/listView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:cacheColorHint="@android:color/transparent"
        android:divider="@null"
        android:scrollbars="none" />

    <View
        android:layout_width="match_parent"
        android:layout_height="0.5dp"
        android:background="@color/gray_d8" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="45dp"
        android:orientation="horizontal">

        <TextView
            android:id="@+id/tv_reset"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="@color/white"
            android:gravity="center"
            android:padding="5dp"
            android:text="清空"
            android:textColor="@color/black_33"
            android:textSize="14sp" />

        <TextView
            android:id="@+id/tv_confirm"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:background="#3e9fed"
            android:gravity="center"
            android:padding="5dp"
            android:text="确定"
            android:textColor="#fefefe"
            android:textSize="14sp" />
    </LinearLayout>

    <View
        android:id="@+id/view_null"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1" />

</LinearLayout>

Here we use MeasureListView, which is to rewrite the OnMeasure function of ListView to recalculate the height of ListView.

public class MeasureListView extends ListView {

    private Context mContext;

    public MeasureListView(Context context) {
        this(context, null);
    }

    public MeasureListView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public MeasureListView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(context);
    }

    private void init(Context context) {
        mContext = context;
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        try {
            Display display = ((Activity) mContext).getWindowManager().getDefaultDisplay();
            DisplayMetrics d = new DisplayMetrics();
            display.getMetrics(d);
            //屏幕的一半
            heightMeasureSpec = MeasureSpec.makeMeasureSpec(d.heightPixels /2 , MeasureSpec.AT_MOST);
        } catch (Exception e) {
            e.printStackTrace();
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}

Finally, the relevant code of MainActivity:

public class MainActivity extends AppCompatActivity {

    @BindView(R.id.tv_title)
    TextView tvTitle;

    private List<FilterBean> lists = new ArrayList<>();
    private FilterPopWindow popWindow=null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ButterKnife.bind(this);
        init();
    }

    private void init() {
        initData();
        initView();
    }



    private void initData() {
        String[] sexs = {"男", "女"};
        String[] colors = {"红色", "浅黄色", "橙子色", "鲜绿色", "青色", "天蓝色", "紫色", "黑曜石色", "白色", "五颜六色"};
        String[] company = {"阿里巴巴", "腾讯集团", "华为技术有限公司", "小米", "百度"};

        FilterBean fb = new FilterBean();
        fb.typeName="性别";
        List<Children> childrenList = new ArrayList<>();
        for (int x = 0; x < sexs.length; x++) {
            Children cd = new Children();
            cd.value=sexs[x];
            childrenList.add(cd);
        }
        fb.children=childrenList;
        lists.add(fb);

        fb = new FilterBean();
        fb.typeName="颜色";
        childrenList = new ArrayList<>();
        for (int x = 0; x < colors.length; x++) {
            Children cd = new Children();
            cd.value=colors[x];
            childrenList.add(cd);
        }
        fb.children=childrenList;
        lists.add(fb);

        fb = new FilterBean();
        fb.typeName="企业";
        childrenList = new ArrayList<>();
        for (int x = 0; x < company.length; x++) {
            Children cd = new Children();
            cd.value=company[x];
            childrenList.add(cd);
        }
        fb.children=childrenList;
        lists.add(fb);
    }

    private void initView() {
        popWindow=new FilterPopWindow(this,lists);
        popWindow.setOnConfirmClickListener(new FilterPopWindow.OnConfirmClickListener() {
            @Override
            public void onConfirmClick() {
                StringBuilder sb = new StringBuilder();
                for (FilterBean fb : lists) {
                    List<Children> cdList = fb.children;
                    for (int x = 0; x < cdList.size(); x++) {
                        Children children = cdList.get(x);
                        if (children.isSelected)
                            sb.append(fb.typeName + ":" + children.value + "；");
                    }
                }
                if (!TextUtils.isEmpty(sb.toString()))
                    Toast.makeText(MainActivity.this, sb.toString(), Toast.LENGTH_LONG).show();
            }
        });
    }

    @OnClick(R.id.tv_title)
    public void onViewClicked() {
        if (popWindow!=null)
        popWindow.showAsDropDown(tvTitle,10);
    }
}

All right here. . .