if 语句不检查通过滚动回收器视图达到的编辑文本的值

Question

我有一个recyclerview，每一行都有一个edittext。用户可以根据需要更改edittext的值，但不应将其保留为空，因为这些值将保存在数据库中。为此，我试图检查编辑文本是否为空。如果任何一行有一个空的edittext，当用户想要保存有一个空值时，就会得到一条消息。这是我写的代码:

public class recyclerview_viewholder : RecyclerView.ViewHolder
{
public TextView rownbr, itemname;
public EditText qty;
public TextView unit;
public LinearLayout linearLayout;

public recyclerview_viewholder(View itemView, Action<int> listener)
: base(itemView)
{
rownbr = itemView.FindViewById<TextView>(Resource.Id.rownbr);
itemname = itemView.FindViewById<TextView>(Resource.Id.laborname);
unit = itemView.FindViewById<TextView>(Resource.Id.days);
qty = itemView.FindViewById<EditText>(Resource.Id.overtime);
linearLayout = itemView.FindViewById<LinearLayout>(Resource.Id.linearLayout);

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

}
}
public class recyclerviewAdapter : RecyclerView.Adapter
{
// Event handler for item clicks:
public event EventHandler<int> ItemClick;
DataTable summary_Requests = new DataTable();
//Context context;
public readonly new_request_items context;
int selected_pos = -1;
private SwipeToDeleteCallback swipeToDeleteCallback;
List<list_item> item_details = new List<list_item>();
public recyclerviewAdapter(new_request_items context, DataTable sum_req, List<list_item> item_details)
{
this.context = context;
summary_Requests = sum_req;
this.item_details = item_details;
}
public recyclerviewAdapter(DataTable sum_req, SwipeToDeleteCallback swipeToDeleteCallback)
{
this.swipeToDeleteCallback = swipeToDeleteCallback;
summary_Requests = sum_req;
}
public override RecyclerView.ViewHolder
OnCreateViewHolder(ViewGroup parent, int viewType)
{
View itemView = LayoutInflater.From(parent.Context).
Inflate(Resource.Layout.recycler_view_request_new_data, parent, false);

recyclerview_viewholder vh = new recyclerview_viewholder(itemView, OnClick);
vh.qty.TextChanged += (sender, e) =>
{
if (vh.qty.Text != "")
try
{
int position = vh.LayoutPosition;
summary_Requests.Rows[position]["itemQty"] = Convert.ToDecimal(vh.qty.Text);
user.zero_val = "Not_exist";
}
catch (System.FormatException exp)
{
var icon = AppCompatResources.GetDrawable(context.Context, Resource.Drawable.error_ic);
icon.SetBounds(0, 0, 50, 50);
vh.qty.SetError("qty can be decimal", icon);
user.zero_val = "exits";
}
else if (vh.qty.Text == "")
{
var icon = AppCompatResources.GetDrawable(context.Context, Resource.Drawable.error_ic);
icon.SetBounds(0, 0, 50, 50);
vh.qty.SetError("value can not be empty", icon);
user.zero_val = "exits";
}
};
vh.ItemView.LongClick += (sender, e) =>
{
int position = vh.AdapterPosition;
string itemcode = summary_Requests.Rows[position]["itemcode"].ToString();

list_item result = item_details.Find(list_item => list_item.item_code == itemcode);
Bundle bundle = new Bundle();
bundle.PutString("result", JsonConvert.SerializeObject(result));
items_info iteminf = new items_info();
iteminf.Arguments = bundle;
iteminf.Cancelable = true;
var SupportFragmentManager = this.context.FragmentManager;
iteminf.Show(SupportFragmentManager, "dialog");

selected_pos = position;
NotifyDataSetChanged();
//fill global variables that need to be passed to detail fragment

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

vh.rownbr.Text = summary_Requests.Rows[position]["rowNumber"].ToString();
vh.itemname.Text = summary_Requests.Rows[position]["name"].ToString();
vh.unit.Text = summary_Requests.Rows[position]["itemsunitcode"].ToString();
vh.qty.Text= summary_Requests.Rows[position]["itemQty"].ToString();
if (selected_pos == position)
vh.ItemView.SetBackgroundColor(Color.ParseColor("#4fa5d5"));
else
vh.ItemView.SetBackgroundColor(Color.LightGray);

}

public void RemoveItem(int position)
{

if (laborers_dt_total.Rows.Count != 0)
{
if (position < laborers_dt_total.Rows.Count && position > -1)
{
laborers_dt_total.Rows.RemoveAt(position);

}
else
{
Toast.MakeText(context.Context, "select an item to delete", ToastLength.Long).Show();
}
}
else if (laborers_dt_total.Rows.Count == 0)
{
Toast.MakeText(context.Context, "no items to delete", ToastLength.Long).Show();
}

for (int i = 0; i < laborers_dt_total.Rows.Count; i++)
{
laborers_dt_total.Rows[i]["rowNumber"] = (i + 1).ToString();

NotifyDataSetChanged();

}
}
public DataTable get_dt_final()
{
DataTable final_dt = summary_Requests.Copy();
return final_dt;
}
public override int ItemCount
{
get { return summary_Requests.Rows.Count; }
}
// Raise an event when the item-click takes place:
void OnClick(int position)
{
if (ItemClick != null)
ItemClick(this, position);
// user.req_pos = position;

}

}

现在它工作得很好，当在回收视图中只有几行，但是当有很多，我必须通过它滚动，如果我保持一个编辑文本为空的行通过滚动，user.zero_val不采取exits的值告诉我，一个编辑文本是空的。在这种情况下我该怎么做?我在哪里检查空编辑文本?提前谢谢。

这是我写的一个简单的代码，希望它能说明我的问题:

这是recycleview的axml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<android.support.v7.widget.RecyclerView
android:minWidth="25px"
android:minHeight="25px"
android:layout_width="match_parent"
android:layout_height="255sp"
android:id="@+id/recyclerView1" />
<Button
android:text="Button"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/button1" />

</LinearLayout>

这是recyclerview的每一行的布局:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"                    
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="@color/light_grey"
android:padding="1dp"
android:layout_marginTop="0.5dp"
android:weightSum="8"
android:gravity="center"
android:id="@+id/linearLayout"

>

<TextView
android:text=""
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_weight="2"
android:id="@+id/rownbr" 
android:background="@drawable/back"
android:paddingLeft="1dp"
android:paddingRight="1dp"
android:textSize="12dp"
android:gravity="center"
android:textColor="#000000"
/>
<TextView
android:text=""
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_weight="4"
android:id="@+id/laborname" 
android:paddingLeft="1dp"
android:paddingRight="1dp"
android:textSize="12dp"
android:gravity="center"
android:textColor="#000000"
android:background="@drawable/back"
android:layout_marginLeft="2dp"/>
<TextView
android:text=""
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_weight="1"
android:id="@+id/days" 
android:paddingLeft="1dp"
android:paddingRight="1dp"
android:textSize="12dp"
android:textColor="#000000"
android:layout_marginLeft="2dp"
android:gravity="center"
android:background="@drawable/back"/>

<EditText
android:text=""
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_weight="1"
android:id="@+id/overtime" 
android:paddingLeft="1dp"
android:paddingRight="1dp"
android:textSize="12dp"
android:textColor="#000000"
android:layout_marginLeft="2dp"
android:gravity="center"
android:background="@drawable/back"/>

</LinearLayout>

这是可绘制的back.xml:

<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle" >
<solid android:color="@android:color/white" />
<stroke android:width="1dip" android:color="#4fa5d5"/>
</shape>

这是填充和管理recyclerview的活动:

public class MainActivity : AppCompatActivity
{
RecyclerView mRecyclerView;
DataTable dt = new DataTable();

RecyclerView.LayoutManager mLayoutManager;
recyclerviewAdapter RecyclerviewAdapter;
protected override void OnCreate(Bundle savedInstanceState)
{
base.OnCreate(savedInstanceState);
// Set our view from the "main" layout resource
SetContentView(Resource.Layout.activity_main);
dt.Columns.Add("rowNumber");
dt.Columns.Add("name");
dt.Columns.Add("itemsunitcode");
dt.Columns.Add("itemQty");
dt.Rows.Add("1", "rana hd", "pcs", "1");
dt.Rows.Add("2", "rana hd1", "pcs", "1");
dt.Rows.Add("3", "rana hd2", "pcs", "1");
dt.Rows.Add("4", "rana hd3", "pcs", "1");
dt.Rows.Add("5", "rana hd4", "pcs", "1");
dt.Rows.Add("6", "rana hd5", "pcs", "1");
dt.Rows.Add("7", "rana hd6", "pcs", "1");
dt.Rows.Add("8", "rana hd7", "pcs", "1");
dt.Rows.Add("9", "rana hd8", "pcs", "1");
dt.Rows.Add("10", "rana hd9", "pcs", "1");


mRecyclerView = FindViewById<RecyclerView>(Resource.Id.recyclerView1);
Button btn= FindViewById<Button>(Resource.Id.button1);
mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.HasFixedSize = true;
mRecyclerView.SetLayoutManager(mLayoutManager);
RecyclerviewAdapter = new recyclerviewAdapter(this, dt);
mRecyclerView.SetAdapter(RecyclerviewAdapter);
btn.Click += delegate
{
if (user.zero_val == "exits")
Toast.MakeText(this, "exists", ToastLength.Long).Show();
if (user.zero_val == "Not_exist")
Toast.MakeText(this, "Not_exist", ToastLength.Long).Show();
};
}
public class recyclerview_viewholder : RecyclerView.ViewHolder
{
public TextView rownbr, itemname;
public EditText qty;
public TextView unit;
public LinearLayout linearLayout;
public recyclerview_viewholder(View itemView, Action<int> listener)
: base(itemView)
{
rownbr = itemView.FindViewById<TextView>(Resource.Id.rownbr);
itemname = itemView.FindViewById<TextView>(Resource.Id.laborname);
unit = itemView.FindViewById<TextView>(Resource.Id.days);
qty = itemView.FindViewById<EditText>(Resource.Id.overtime);
linearLayout = itemView.FindViewById<LinearLayout>(Resource.Id.linearLayout);
itemView.Click += (sender, e) => listener(base.LayoutPosition);
}
}
public class recyclerviewAdapter : RecyclerView.Adapter
{
// Event handler for item clicks:
public event EventHandler<int> ItemClick;
DataTable summary_Requests = new DataTable();
//Context context;
public readonly MainActivity context;
int selected_pos = -1;
public recyclerviewAdapter(MainActivity context, DataTable sum_req)
{
this.context = context;
summary_Requests = sum_req;

}

public override RecyclerView.ViewHolder
OnCreateViewHolder(ViewGroup parent, int viewType)
{
View itemView = LayoutInflater.From(parent.Context).
Inflate(Resource.Layout.recyclerview_data, parent, false);

recyclerview_viewholder vh = new recyclerview_viewholder(itemView, OnClick);
vh.qty.TextChanged += (sender, e) =>
{
if (vh.qty.Text != "")
try
{
int position = vh.LayoutPosition;
summary_Requests.Rows[position]["itemQty"] = Convert.ToDecimal(vh.qty.Text);
user.zero_val = "Not_exist";
}
catch (System.FormatException exp)
{
var icon = AppCompatResources.GetDrawable(context, Resource.Drawable.error_ic);
icon.SetBounds(0, 0, 50, 50);
vh.qty.SetError("qty can be decimal", icon);
user.zero_val = "exits";
}
else if (vh.qty.Text == "")
{
var icon = AppCompatResources.GetDrawable(context, Resource.Drawable.error_ic);
icon.SetBounds(0, 0, 50, 50);
vh.qty.SetError("value can not be empty", icon);
user.zero_val = "exits";
}
};
vh.ItemView.LongClick += (sender, e) =>
{
int position = vh.AdapterPosition;

selected_pos = position;
NotifyDataSetChanged();

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

vh.rownbr.Text = summary_Requests.Rows[position]["rowNumber"].ToString();
vh.itemname.Text = summary_Requests.Rows[position]["name"].ToString();
vh.unit.Text = summary_Requests.Rows[position]["itemsunitcode"].ToString();
vh.qty.Text = summary_Requests.Rows[position]["itemQty"].ToString();
if (selected_pos == position)
vh.ItemView.SetBackgroundColor(Color.ParseColor("#4fa5d5"));
else
vh.ItemView.SetBackgroundColor(Color.LightGray);
}

public DataTable get_dt_final()
{
DataTable final_dt = summary_Requests.Copy();
return final_dt;
}
public override int ItemCount
{
get { return summary_Requests.Rows.Count; }
}
// Raise an event when the item-click takes place:
void OnClick(int position)
{
if (ItemClick != null)
ItemClick(this, position);
// user.req_pos = position;

}
}
}
}

这是用户类:

public static class user
{
public static string zero_val = "";
}

Answer 1

如果我正确理解你的意思，我认为在user类中使用变量zero_val来指示是否存在空值是不正确的。例如，如果你为第一个EditText输入了一个空值，那么zero_val的值将被更改为Not_exist，然后如果我们为第二个EditText输入另一个空值，那么zero_val的值也将被更改为Not_exist，之后，如果我们将第二个EditText更改为正确的值，那么zero_val的值将被更改为exits。但是现在，实际上第一个EditText仍然是空的。

我认为您可以在单击按钮时验证表DataTable的值。

你可以参考下面的代码:

btn.Click += delegate
{
bool hasEmpty = false ;
foreach (DataRow row in dt.Rows)
{
string itemQty = row["itemQty"].ToString();
string rowNumber = row["rowNumber"].ToString();
System.Diagnostics.Debug.WriteLine("rowNumber =" + rowNumber  + "< ---  > itemQty = " + itemQty);
if (string.IsNullOrEmpty(itemQty)) {
hasEmpty = true;
}
}
//if (user.zero_val.Equals("exits"))
//    Toast.MakeText(this, "exists", ToastLength.Long).Show();
//if (user.zero_val.Equals("Not_exist"))
//    Toast.MakeText(this, "Not_exist", ToastLength.Long).Show();
if (!hasEmpty)
Toast.MakeText(this, "exists", ToastLength.Long).Show();
else
Toast.MakeText(this, "Not_exist", ToastLength.Long).Show();
};

另外，修改RecyclerviewAdapter中的TextChanged函数:

vh.qty.TextChanged += (sender, e) =>
{
if (!vh.qty.Text.Equals(""))
try
{
int position = vh.LayoutPosition;
summary_Requests.Rows[position]["itemQty"] = Convert.ToDecimal(vh.qty.Text);
}
catch (System.FormatException exp)
{
var icon = AppCompatResources.GetDrawable(context, Resource.Drawable.error);
icon.SetBounds(0, 0, 50, 50);
vh.qty.SetError("qty can be decimal", icon);
//store a empty value for this textview
int position = vh.LayoutPosition;
summary_Requests.Rows[position]["itemQty"] = "";
}
else if (vh.qty.Text.Equals(""))
{
var icon = AppCompatResources.GetDrawable(context, Resource.Drawable.error);
int position = vh.LayoutPosition;
//store a empty value for this textview
summary_Requests.Rows[position]["itemQty"] = "";
icon.SetBounds(0, 0, 50, 50);
vh.qty.SetError("value can not be empty", icon);
}
};