Question

我希望在stickyheaderlistview（lib）中淡出第一个可见的标头。我如何淡出列表视图中的第一个可见标题。请举个例子。谢谢。如果您观察日期标题，如果在一段时间后没有用户交互，它将隐藏

Answer 1

编译：

compile 'se.emilsjolander:stickylistheaders:2.1.3'

在适配器中

public class ChatAdapter extends BaseAdapter implements StickyListHeadersAdapter {

    private Activity mActivity;
    private SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
    private SimpleDateFormat dateformat = new SimpleDateFormat("hh:mm a");
    private SimpleDateFormat format1 = new SimpleDateFormat("ddMMyyyy");
    private SimpleDateFormat headerdateformat = new SimpleDateFormat("dd MMMM yyyy");
    private Date date = null;
    private String msgDate = "";
    private Date headerDate = null;
    private String msgHeader = "";
    private String msg = "";
    private String mName = "";
    private int day = 0;
List<GroupChatHistoryData> mChatArrayList = new ArrayList<>();

    public ChatAdapter(Activity mActivity,List<GroupChatHistoryData> mChatArrayList) {
        this.mActivity = mActivity;
this.mChatArrayList = mChatArrayList;
    }

    @Override
    public int getCount() {
        return mChatArrayList.size();
    }

    @Override
    public Object getItem(int position) {
        return mChatArrayList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final ViewHolder holder;

        if (convertView == null) {

            LayoutInflater inflater = (LayoutInflater) mActivity.
                    getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            /****** Inflate tabitem.xml file for each row ( Defined below ) *******/
            convertView = inflater.inflate(R.layout.chat_details_row_item, null);

            holder = new ViewHolder();

            holder.receive_message_text = (TextView) convertView.findViewById(R.id.receive_message_text);
            holder.receive_message_date = (TextView) convertView.findViewById(R.id.receive_message_date);
            holder.receive_member_name = (TextView) convertView.findViewById(R.id.receive_member_name);
            holder.sent_message_date = (TextView) convertView.findViewById(R.id.sent_message_date);
            holder.sent_message_text = (TextView) convertView.findViewById(R.id.sent_message_text);

            holder.chat_receive_layout = (LinearLayout) convertView.findViewById(R.id.chat_receive_layout);
            holder.sent_msg_ll = (LinearLayout) convertView.findViewById(R.id.sent_msg_ll);

            convertView.setTag(holder);
        } else {
            holder = (ViewHolder) convertView.getTag();
        }

        final GroupChatHistoryData bean = mChatArrayList.get(position);

        try {
            if (bean.getTime() != null && !bean.getTime().equalsIgnoreCase("")) {
                date = format.parse(bean.getTime());
            }
        } catch (ParseException e) {
            e.printStackTrace();
        }
        if (date != null) {
            msgDate = dateformat.format(date);
        }

        msg = bean.getMessage();


// your rest views

        return convertView;
    }


    @Override
    public View getHeaderView(int position, View convertView, ViewGroup parent) {
        final HeaderViewHolder holder;
        LayoutInflater inflater = LayoutInflater.from(mActivity);
        if (convertView == null) {
            convertView = inflater.inflate(R.layout.chat_header, parent, false);
            holder = new HeaderViewHolder();

            holder.headerDate = (TextView) convertView.findViewById(R.id.header_date);

            convertView.setTag(holder);

        } else {
            holder = (HeaderViewHolder) convertView.getTag();
        }

        GroupChatHistoryData bean = mChatArrayList.get(position);

        try {
            if (bean.getDatetime() != null && !bean.getDatetime().equalsIgnoreCase("")) {
                headerDate = format1.parse(bean.getDatetime());
            }
        } catch (ParseException e) {
            e.printStackTrace();
        }

        if (headerDate != null) {
            msgHeader = headerdateformat.format(headerDate);
        }

        if (show(msgHeader) == 0) {
            holder.headerDate.setText("TODAY");
        } else if (show(msgHeader) == -1) {
            holder.headerDate.setText("YESTERDAY");
        } else {
            holder.headerDate.setText(msgHeader);
        }

        return convertView;
    }

    private class HeaderViewHolder {
        private TextView headerDate;
    }

    @Override
    public long getHeaderId(int position) {
        String mDate = mChatArrayList.get(position).getDatetime();
        int mDatePos = Integer.parseInt(mDate);
        return mDatePos;
    }

    private class ViewHolder {
        TextView receive_message_text;
        TextView receive_message_date;
        TextView receive_member_name;
        TextView sent_message_date;
        TextView sent_message_text;

        LinearLayout chat_receive_layout;
        LinearLayout sent_msg_ll;
    }

    private int show(String time) {
        try {
            String outputPattern = "dd MMMM yyyy";
            SimpleDateFormat format = new SimpleDateFormat(outputPattern);

            Date Date1 = format.parse(getdate());
            Date Date2 = format.parse(time);
            long mills = Date2.getTime() - Date1.getTime();
            long Day1 = mills / (1000 * 60 * 60);

            day = (int) Day1 / 24;

        } catch (Exception e) {
            e.printStackTrace();
        }
        return day;
    }


    private String getdate() {
        String time = "";
        try {
            String outputPattern = "dd MMMM yyyy";

            Calendar c = Calendar.getInstance();
            SimpleDateFormat df = new SimpleDateFormat(outputPattern);
            time = df.format(c.getTime());

        } catch (Exception e) {
            e.printStackTrace();
        }
        return time;
    }

}

chat_header.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="10dp">

        <TextView
            android:id="@+id/header_date"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:background="#BDD9E4"
            android:gravity="center"
            android:padding="10dp"
            android:textAllCaps="true"
            android:textSize="12sp"
            android:textColor="@color/gray"
            android:textStyle="bold" />

    </RelativeLayout>

</RelativeLayout>

GroupChatHistoryData Bean是这样的：

public class GroupChatHistoryData {


    private SimpleDateFormat headerdateformat = new SimpleDateFormat("ddMMyyyy");
    private Date headerDate = null;
    private Date mTime = null;
    private SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
    private SimpleDateFormat timeformat = new SimpleDateFormat("hh:mm a");

    @SerializedName("user_id")
    @Expose
    private String userId;
    @SerializedName("group_id")
    @Expose
    private String groupId;
    @SerializedName("message")
    @Expose
    private String message;
    @SerializedName("datetime")
    @Expose
    private String datetime;
    @SerializedName("fname")
    @Expose
    private String fname;
    @SerializedName("time")
    @Expose
    private String time;

    public String getUserId() {
        return userId;
    }

    public void setUserId(String userId) {
        this.userId = userId;
    }

    public String getGroupId() {
        return groupId;
    }

    public void setGroupId(String groupId) {
        this.groupId = groupId;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public String getDatetime() {

        String date = "";
        try {
            if (datetime != null && !datetime.equalsIgnoreCase("")) {
                headerDate = format.parse(datetime);
            }
        } catch (ParseException e) {
            e.printStackTrace();
        }
        if (headerDate != null) {
            date = headerdateformat.format(headerDate);
        }

        return date;
    }

    public void setDatetime(String datetime) {
        this.datetime = datetime;
    }

    public String getFname() {
        return fname;
    }

    public void setFname(String fname) {
        this.fname = fname;
    }


    public boolean isMine() {
        return isMine;
    }

    public void setMine(boolean mine) {
        isMine = mine;
    }

    public boolean isMine = false;

    public String getTime() {

        return time;
    }

    public void setTime(String time) {
        this.time = time;
    }

}

Answer 2

我认为你应该尝试使用ObservableScrollView。

https://github.com/ksoichiro/Android-ObservableScrollView

如何在列表视图中淡出标头，如whatsapp

2 个答案: