Hello i have an error:
my code:
the clv code:
and the error:
my code:
B4X:
Dim tv1 As CustomListView
tv1.Initialize(Me, "tv1")
tv1.DefaultTextBackgroundColor = Colors.Transparent
tv1.DefaultTextColor = Colors.White
tv1.AddTextItem("my text", Null)the clv code:
B4X:
#Event: ItemClick (Index As Int, Value As Object)
Sub Class_Globals
Private sv As ScrollView
Private items As List
Private panels As List
Private dividerHeight As Float
Private EventName As String
Private CallBack As Object
Private su As StringUtils
Public DefaultTextSize As Int
Public DefaultTextColor As Int
Public DefaultTextBackgroundColor As Int
Private DefaultTextBackground As Object
Private PressedDrawable As ColorDrawable
End Sub
Public Sub Initialize (vCallback As Object, vEventName As String)
EventName = vEventName
CallBack = vCallback
sv.Initialize2(0, "sv")
items.Initialize
panels.Initialize
'these defaults will be used when the view is added by code
dividerHeight = 2dip
sv.Color = 0xFFD9D7DE
sv.Color = Colors.Transparent
DefaultTextColor = Colors.White
DefaultTextSize = 16
DefaultTextBackgroundColor = Colors.Black
DefaultTextBackground = Null
PressedDrawable.Initialize(0xFF7EB4FA, 2dip)
End Sub
'Returns a view object that holds the list.
Public Sub AsView As View
Return sv
End Sub
Public Sub DesignerCreateView(base As Panel, lbl As Label, props As Map)
ReplaceBasePanelWithView(base, sv)
sv.Color = props.Get("DividerColor")
dividerHeight = DipToCurrent(props.Get("DividerHeight")) 'need to scale the value
PressedDrawable.Initialize(props.Get("PressedColor"), 2dip)
DefaultTextSize = lbl.TextSize
DefaultTextColor = lbl.TextColor
DefaultTextBackground = base.Background
End Sub
Private Sub ReplaceBasePanelWithView(base As Panel, view As View)
Dim jo As JavaObject = base
Dim parent As Panel = jo.RunMethod("getParent", Null)
parent.AddView(view, base.Left, base.Top, base.Width, base.Height)
base.RemoveView
End Sub
'Clears all items.
Public Sub Clear
items.Clear
panels.Clear
sv.Panel.Height = 0
For i = sv.Panel.NumberOfViews - 1 To 0 Step -1
sv.Panel.RemoveViewAt(i)
Next
End Sub
'Returns the number of items.
Public Sub GetSize As Int
Return items.Size
End Sub
'Returns the Panel stored at the specified index.
Public Sub GetPanel(Index As Int) As Panel
Dim p As Panel
p = panels.Get(Index) 'this is the parent panel
Return p.GetView(0)
End Sub
'Returns the value stored at the specified index.
Public Sub GetValue(Index As Int) As Object
Return items.Get(Index)
End Sub
'Removes the item at the specified index.
Public Sub RemoveAt(Index As Int)
Dim removePanel, p As Panel
removePanel = panels.Get(Index)
For i = Index + 1 To items.Size - 1
p = panels.Get(i)
p.Tag = i - 1
p.Top = p.Top - removePanel.Height - dividerHeight
Next
sv.Panel.Height = sv.Panel.Height - removePanel.Height - dividerHeight
items.RemoveAt(Index)
panels.RemoveAt(Index)
removePanel.RemoveView
End Sub
'Adds a text item. The item height will be adjusted based on the text.
Public Sub AddTextItem(Text As String, Value As Object)
InsertAtTextItem(items.Size, Text, Value)
End Sub
'Inserts a text item at the specified index.
Public Sub InsertAtTextItem(Index As Int, Text As String, Value As Object)
Dim pnl As Panel
pnl.Initialize("")
Dim lbl As Label
lbl.Initialize("")
lbl.Gravity = Bit.Or(Gravity.CENTER_VERTICAL, Gravity.LEFT)
pnl.AddView(lbl, 5dip, 2dip, sv.Width - 5dip, 20dip)
lbl.Text = Text
lbl.TextSize = DefaultTextSize
lbl.TextColor = DefaultTextColor
If DefaultTextBackground <> Null Then
pnl.Background = DefaultTextBackground
Else
pnl.Color = DefaultTextBackgroundColor
End If
Dim minHeight As Int
minHeight = su.MeasureMultilineTextHeight(lbl, Text)
lbl.Height = Max(50dip, minHeight)
InsertAt(Index, pnl, lbl.Height + 2dip, Value)
End Sub
'Adds a custom item at the specified index.
Public Sub InsertAt(Index As Int, Pnl As Panel, ItemHeight As Int, Value As Object)
Dim sd As StateListDrawable
sd.Initialize
sd.AddState(sd.State_Pressed, PressedDrawable)
sd.AddCatchAllState(Pnl.Background)
'create another panel to handle the click event
Dim p As Panel
p.Initialize("panel")
p.Background = sd
Dim cd As ColorDrawable
cd.Initialize(Colors.Transparent, 0)
Pnl.Background = cd
p.AddView(Pnl, 0, 0, sv.Width, ItemHeight)
p.Tag = Index
If Index = items.Size Then
items.Add(Value)
panels.Add(p)
Dim top As Int
If Index = 0 Then top = dividerHeight Else top = sv.Panel.Height
sv.Panel.AddView(p, 0, top, sv.Width, ItemHeight)
Else
Dim top As Int
If Index = 0 Then
top = dividerHeight
Else
Dim previousPanel As Panel
previousPanel = panels.Get(Index - 1)
top = previousPanel.top + previousPanel.Height + dividerHeight
End If
Dim p2 As Panel
For i = Index To panels.Size - 1
p2 = panels.Get(i)
p2.top = p2.top + ItemHeight + dividerHeight
p2.Tag = i + 1
Next
items.InsertAt(Index, Value)
panels.InsertAt(Index, p)
sv.Panel.AddView(p, 0, top, sv.Width, ItemHeight)
End If
sv.Panel.Height = sv.Panel.Height + ItemHeight + dividerHeight
If items.Size = 1 Then sv.Panel.Height = sv.Panel.Height + dividerHeight
End Sub
'Adds a custom item.
Public Sub Add(Pnl As Panel, ItemHeight As Int, Value As Object)
InsertAt(items.Size, Pnl, ItemHeight, Value)
End Sub
'Scrolls the list to the specified item.
Public Sub JumpToItem(Index As Int)
Dim top As Int
Dim p As Panel
For i = 0 To Min(Index - 1, items.Size - 1)
p = panels.Get(i)
top = top + p.Height + dividerHeight
Next
sv.ScrollPosition = top
'The scroll position doesn't always gets updated without two calls to DoEvents
DoEvents
sv.ScrollPosition = top
DoEvents
End Sub
Private Sub Panel_Click
If SubExists(CallBack, EventName & "_ItemClick") Then
Dim v As View
v = Sender
CallSub3(CallBack, EventName & "_ItemClick", v.Tag, items.Get(v.Tag))
End If
End Sub
'Returns the index of the item that holds the given view.
Public Sub GetItemFromView(v As View) As Int
Dim parent = v, current As Object
Do While (parent Is Panel) = False Or sv.Panel <> parent
current = parent
Dim jo As JavaObject = current
parent = jo.RunMethod("getParent", Null)
Loop
v = current
Return v.Tag
End Suband the error:
B4X:
Error occurred on line: 118 (CustomListView)
java.lang.NullPointerException: Attempt to read from field 'int android.view.ViewGroup$LayoutParams.width' on a null object reference
at anywheresoftware.b4a.objects.ViewWrapper.getWidth(ViewWrapper.java:140)
at de.example.app.dev.customlistview._insertattextitem(customlistview.java:381)
at de.example.app.dev.customlistview._addtextitem(customlistview.java:216)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:697)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:339)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:246)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:134)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:157)
at anywheresoftware.b4a.debug.Debug.delegate(Debug.java:262)
at de.example.app.dev.main._setuppage4(main.java:957)
at de.example.app.dev.main._isochron_b_click(main.java:3001)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:697)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:339)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:246)
at java.lang.reflect.Method.invoke(Native Method)
at anywheresoftware.b4a.ShellBA.raiseEvent2(ShellBA.java:134)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:157)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:153)
at anywheresoftware.b4a.objects.ViewWrapper$1.onClick(ViewWrapper.java:78)
at android.view.View.performClick(View.java:5226)
at android.view.View$PerformClick.run(View.java:21266)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:168)
at android.app.ActivityThread.main(ActivityThread.java:5845)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:687)
