Question

我在使用自定义值的NumberPicker时遇到问题。打开对话框时，我通过在自定义数组数组中查找索引并将NumberPicker的值设置为此索引来获取要在NumberPicker中显示的值。跟踪显示在NumberPicker.Value中找到并设置了正确的索引;但是，NumberPicker显示不同索引的值。

在附图中，我的值为1/4，但显示为1/45。如果我选择1/6的值，它将显示为1/60。值为1，显示为1/1000。如果我选择它，正确的索引保存在NumberPicker.Value中，所以我得到了所需的值，只是显示混乱，似乎选择了一个与所需值紧密匹配的东西（1/4为1/45， 1/60等1/60，并忽略我设置的数组中的索引。如果我选择值2,3等，则NumberPicker中会显示正确的值。

以下是相关代码，问题是在模拟器和真实的Android设备上。

public class MeasuredExposureDialog : Android.Support.V4.App.DialogFragment
{
private ReciprocityAdapter _mAdapter = null;

private string[] shutterSpeeds = { "1/1000", "1/750", "1/500", "1/350", "1/180", "1/125", "1/90", "1/60", "1/45", "1/30", "1/20", "1/15", "1/10", "1/8", "1/6", **"1/4"**, "1/3", "1/2", "1", "2", "3", "4", "5", "6", "7", "8", "9", "10"
    , "11", "12", "13", "14", "15", "16", "17", "18", "19", "20", "21", "22", "23", "24", "25", "26", "27", "28", "29", "30", "31", "32", "33", "34", "35", "36", "37", "38", "39", "40"
    , "41", "42", "43", "44", "45", "46", "47", "48", "49", "50", "51", "52", "53", "54", "55", "56", "57", "58", "59", "60", "61", "62", "63", "64", "65", "66", "67", "68", "69", "70"
    , "71", "72", "73", "74", "75", "76", "77", "78", "79", "80", "81", "82", "83", "84", "85", "86", "87", "88", "89", "90", "91", "92", "93", "94", "95", "96", "97", "98", "99", "100"
    , "101", "102", "103", "104", "105", "106", "107", "108", "109", "110", "111", "112", "113", "114", "115", "116", "117", "118", "119", "120", "121", "122", "123", "124", "125", "126", "127", "128", "129", "130"
    , "131", "132", "133", "134", "135", "136", "137", "138", "139", "140", "141", "142", "143", "144", "145", "146", "147", "148", "149", "150", "151", "152", "153", "154", "155", "156", "157", "158", "159", "160"
    , "161", "162", "163", "164", "165", "166", "167", "168", "169", "170", "171", "172", "173", "174", "175", "176", "177", "178", "179", "180", "181", "182", "183", "184", "185", "186", "187", "188", "189", "190"
    , "191", "192", "193", "194", "195", "196", "197", "198", "199", "200", "201", "202", "203", "204", "205", "206", "207", "208", "209", "210", "211", "212", "213", "214", "215", "216", "217", "218", "219", "220"
};

public static MeasuredExposureDialog NewInstance(Bundle bundle)
{
    MeasuredExposureDialog fragment = new MeasuredExposureDialog();
    fragment.Arguments = bundle;
    return fragment;
}

public ReciprocityAdapter Adapter
{
    set{ _mAdapter = value; }
}

public override Dialog OnCreateDialog(Bundle savedInstanceState)
    {
        AlertDialog.Builder builder = new AlertDialog.Builder(Activity);
        // Get the layout inflater
        LayoutInflater inflater = Activity.LayoutInflater;

        // Inflate and set the layout for the dialog
        // Pass null as the parent view because its going in the dialog layout
        View view = inflater.Inflate(Resource.Layout.numberpicker, null);
        builder.SetView(view);
        builder.SetTitle("Measured exposure");

        NumberPicker numberPicker = view.FindViewById<NumberPicker>(Resource.Id.numberPicker);
        numberPicker.MaxValue = shutterSpeeds.Length - 1;
        numberPicker.MinValue = 0;
        numberPicker.SetDisplayedValues(shutterSpeeds);
        numberPicker.WrapSelectorWheel = true;

        string value = _mAdapter.GetEntrySetting(4);

        Log.Info("myapp", "Setting stored value: " + value);

        for (int i = 0; i < shutterSpeeds.Length; i++)
        {
            if (shutterSpeeds[i] == value)
            {
                numberPicker.Value = i;
                Log.Info("myapp", "Setting value to index: " + i);
                break;
            }
        }

        //numberPicker.ClearFocus();

        // Add action buttons
        builder.SetPositiveButton("Select", (senderAlert, args) = >
        {
            _mAdapter.SetEntry(4, shutterSpeeds[numberPicker.Value]);
            _mAdapter.NotifyDataSetChanged();
        });

        builder.SetNegativeButton("Cancel", (senderAlert, args) = >
        {
        });

        return builder.Create();
    }
}

适配器代码：

using Android.Content;
using Android.Graphics;
using Android.Support.V7.Widget;
using Android.Views;
using Android.Widget;
using System;
using System.Collections.Generic;

namespace Reciprocity.Fragments
{
public class ReciprocityAdapter : RecyclerView.Adapter
{
    private View _itemView = null;
    private List<Entry> _entryList;

    public string GetEntrySetting(int position)
    {
        return _entryList[position].setting;
    }

    public void StoreEnvironment()
    {
        //store
        var prefs = Android.App.Application.Context.GetSharedPreferences("Reciprocity2", FileCreationMode.Private);
        var prefEditor = prefs.Edit();

        if (_entryList[0].setting != "Tap to select a film")
            prefEditor.PutString("selectedFilm", _entryList[0].setting);

        prefEditor.PutString("measuredSeconds", _entryList[4].setting);

        prefEditor.PutBoolean("useBGR", true);

        prefEditor.PutString("filterFactor", _entryList[1].setting);
        prefEditor.PutString("lensExtension", _entryList[3].setting);
        prefEditor.PutString("focalLength", _entryList[2].setting);

        prefEditor.Commit();
    }

    public void RestoreEnvironment()
    {
        var prefs = Android.App.Application.Context.GetSharedPreferences("Reciprocity2", FileCreationMode.Private);
        var selectedFilm = prefs.GetString("selectedFilm", null);

        if (selectedFilm != null)
        {
            _entryList[0].setting = selectedFilm;
        }

        _entryList[4].setting = prefs.GetString("measuredSeconds", "Tap to select");
        _entryList[1].setting = prefs.GetString("filterFactor", "Tap to select");
        _entryList[3].setting = prefs.GetString("lensExtension", "Tap to select");
        _entryList[2].setting = prefs.GetString("focalLength", "Tap to select");
    }

    public ReciprocityAdapter(List<Entry> entries)
    {
        _entryList = entries;
    }

    public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int viewType)
    {
        // Inflate the CardView for the photo:
        _itemView = LayoutInflater.From(parent.Context).Inflate(Resource.Layout.cardview, parent, false);

        // Create a ViewHolder to hold view references inside the CardView:
        ReciprocityViewHolder vh = new ReciprocityViewHolder(_itemView, OnClick);

        return vh;
    }

    public override void OnBindViewHolder(RecyclerView.ViewHolder holder, int position)
    {
        ReciprocityViewHolder vh = holder as ReciprocityViewHolder;

        vh.category.Text = _entryList[position].category;
        vh.setting.Text = _entryList[position].setting;

        vh.image.SetImageResource(_entryList[position].colorbar);
        vh.image.SetAdjustViewBounds(true);

        CardView cv = vh.ItemView.FindViewById<CardView>(Resource.Id.cv);
        cv.SetCardBackgroundColor((position == 5) ? Color.Yellow : Color.White);
    }

    private void OnClick(int position)
    {
        if (ItemClick != null)
            ItemClick(this, position);
    }

    public override int ItemCount
    {
        get
        {
            return _entryList.Count;
        }
    }

    public event EventHandler<int> ItemClick;
}

public class ReciprocityViewHolder : RecyclerView.ViewHolder
{
    public ImageView image { get; private set; }
    public TextView category { get; private set; }
    public TextView setting { get; private set; }

    public ReciprocityViewHolder(View itemView, Action<int> listener)
        : base(itemView)
    {
        image = itemView.FindViewById<ImageView>(Resource.Id.colorBar);
        setting = itemView.FindViewById<TextView>(Resource.Id.reciprocitySetting);
        category = itemView.FindViewById<TextView>(Resource.Id.reciprocityCategory);

        itemView.Click += (sender, e) => listener(base.AdapterPosition);
    }
}

XML：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="16dp">
    <Space
        android:layout_width="1dp"
        android:layout_height="10dp" />
    <NumberPicker
        android:id="@+id/numberPicker"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:layout_height="wrap_content"
        android:layout_width="wrap_content"
        android:layout_gravity="top|center_horizontal"
        android:descendantFocusability="blocksDescendants"
        android:gravity="center" />
    <Space
        android:layout_width="1dp"
        android:layout_height="15dp" />
</LinearLayout>

输出如下：

Setting stored value: 1/4
Setting value to index: 15

它在对话框中显示的方式：

screen

知道发生了什么事吗？

NumberPicker显示不正确的值

0 个答案: