Android Question how the experts manage to see / use this type of log command to solve the problems of preference dialog ?

[AnandGupta]

Recently I asked for few solutions on preference dialog and got them, thanks to Experts here.

Now my query is, how the experts manage to see / use this type of log command to solve the problems ?
for example,

    For i = 0 To pref.PrefItems.Size - 1
        Dim pi As B4XPrefItem = pref.PrefItems.Get(i)
        If pi.ItemType = pref.TYPE_SHORTOPTIONS Then
            Dim c As B4XComboBox=pref.CustomListView1.GetPanel(i).GetView(1).Tag
            c.cmbBox.TextSize=18
        End If
    Next

all solutions are inside the loop,

    For i = 0 To pref.PrefItems.Size - 1
...
...
    Next

But how they get to items like below which looks very complicated to me,

pref.CustomListView1.GetPanel(i).GetView(0).GetView(0).TextColor = 0xFFA52A2A

I want to understand them so that I can also try to solve before putting them on the Forum.

 

[William Lancee]

If you access to the source code (which we do in this case, B4XLibs), you can see how the nodes are constructed and which piece goes where.
But I have also used the loop below to analyze the structure.

    Dim nodeOfInterest As B4XView = Root  'as an example
    Dim nChildren As Int = nodeOfInterest.NumberOfViews
    For index = 0 To nChildren  - 1
        Dim obj As Object = Root.GetView(index)
        Try
            Log(index & TAB & GetType(obj))
        Catch
            Log(LastException)
        End Try
    Next

 

[AnandGupta]

So repeatedly check for all child ? Okay.

But then .TAG is also used somewhere, so check that too ?

 

[William Lancee]

Yes. Recursively. I do it manually, but you could write a Sub to do it.
You do have to check that the object has a tag.

        Try
            If obj Is B4XView Then
                Log(index & TAB & GetType(obj) & TAB & GetType(obj.As(B4XView).Tag))
            Else
                Log(index & TAB & GetType(obj))
            End If
        Catch
            Log(LastException)
        End Try

 

[William Lancee]

An example of a recursive Sub
use on B4XView node: analyzeNode(Root) 'as an example

'nodeDepth and indents are global
Private Sub analyzeNode(theNode As B4XView)
    nodeDepth = nodeDepth + 1
    Dim nChildren As Int = theNode.NumberOfViews
    For index = 0 To nChildren  - 1
        Dim obj As Object = theNode.GetView(index)
        Try
            If obj Is B4XView Then
                Log(indents.SubString2(0, nodeDepth - 1) & TAB & index & TAB & GetType(obj) & TAB & GetType(obj.As(B4XView).Tag))
                analyzeNode(obj)
            Else
                Log(index & TAB & GetType(obj))
            End If
        Catch
            Log(indents.SubString2(0, nodeDepth - 1) & TAB & LastException)
            nodeDepth = nodeDepth - 1
        End Try
    Next
    nodeDepth = nodeDepth - 1
End Sub
'ON LOG:
'    0    anywheresoftware.b4j.objects.PaneWrapper$ConcretePaneWrapper$NonResizePane    b4j.example.b4xfloattextfield
'        0    javafx.scene.control.TextField    java.lang.String
'            (ClassCastException) java.lang.ClassCastException: class javafx.scene.control.TextField cannot be cast To class javafx.scene.layout.Pane (javafx.scene.control.TextField Is in module javafx.controls of loader 'app'; javafx.scene.layout.Pane is in module javafx.graphics of loader 'app')
'        1    javafx.scene.image.ImageView    java.lang.String
'            (ClassCastException) java.lang.ClassCastException: class javafx.scene.image.ImageView cannot be cast To class javafx.scene.layout.Pane (javafx.scene.image.ImageView And javafx.scene.layout.Pane are in module javafx.graphics of loader 'app')
'        2    javafx.scene.control.Label    java.lang.String
'            (ClassCastException) java.lang.ClassCastException: class javafx.scene.control.Label cannot be cast To class javafx.scene.layout.Pane (javafx.scene.control.Label Is in module javafx.controls of loader 'app'; javafx.scene.layout.Pane is in module javafx.graphics of loader 'app')
'        3    javafx.scene.control.Label    java.lang.String
'            (ClassCastException) java.lang.ClassCastException: class javafx.scene.control.Label cannot be cast To class javafx.scene.layout.Pane (javafx.scene.control.Label Is in module javafx.controls of loader 'app'; javafx.scene.layout.Pane is in module javafx.graphics of loader 'app')
'    1    javafx.scene.control.Button    java.lang.String
'        (ClassCastException) java.lang.ClassCastException: class javafx.scene.control.Button cannot be cast To class javafx.scene.layout.Pane (javafx.scene.control.Button Is in module javafx.controls of loader 'app'; javafx.scene.layout.Pane is in module javafx.graphics of loader 'app')

 

[PaulMeuris]

You could use my B4XSources application to review the B4XPreferencesDialog.b4xlib file (PreferencesDialog.bas).
You can also use the GetAllViewsRecursive method:

    For Each vw As B4XView In pnl.GetAllViewsRecursive
        Log(vw)
        Log("tag: " & vw.Tag)
    Next

Or for a CustomListView:

    For i = 0 To clv1.Size -1
        For Each vw As B4XView In clv1.GetPanel(i).GetAllViewsRecursive
            Log(vw)
        Next
    Next

Each item in a CustomListView has a panel and in that panel you can add other views.
The AddTextItem method has a panel and a label.

 

[Mahares]

Now my query is, how the experts manage to see / use this type of log command to solve the problems ?
for example,

Let us start by saying I am no expert here. I take a different approach. When I get stuck, here is what I do:
1. Unzip the B4XPreferencesDialog.b4xlib. lib.
2. Inside it you will see a Files folder that has all the internal layouts used by B4XPref for B4A, B4J and B4i.
3. Let us take a look at 'shortoptions.bal' layout. Open it in any B4A project. You will see a label and a B4XCombobox. In the tree hierarchy, B4XComboBox is the 2nd view. But since a B4XCombobox is an XUI Views customview, the object resides in its Tag. Hence, it is referred to as: GetView(1).Tag. See screenshot attached.

If pi.ItemType = pref.TYPE_SHORTOPTIONS Then
            Dim c As B4XComboBox=pref.CustomListView1.GetPanel(i).GetView(1).Tag

The 'textitem.bal' layout has only a B4XFloatTextField. Hence: GetView(0).Tag
Same for these 3: pi.ItemType = prefdialog.TYPE_TEXT Or pi.ItemType = prefdialog.TYPE_NUMBER Or pi.ItemType = prefdialog.TYPE_PASSWORD
Dim ft As B4XFloatTextField = prefdialog.CustomListView1.GetPanel(i).GetView(0).Tag

 

[AnandGupta]

Let us take a look at 'shortoptions.bal' layout. Open it in any B4A project. You will see a label and a B4XCombobox. In the tree hierarchy, B4XComboBox is the 2nd view. But since a B4XCombobox is an XUI Views customview, the object resides in its Tag. Hence, it is referred to as: GetView(1).Tag. See screenshot attached.

This gives me more clear idea.
Thanks a lot.