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Xamarin Navigation Bar Hide Hamburger Menu

I need to hide the hamburger menu on certain pages but still display information in then navbar. I don’t know of any way to accomplish this.
Also, I need the navbar to stay fixed to the top of the screen but it’s getting cut off when the keyboard pops up.
How can I go about this?

FlyoutPage.ShouldShowToolbarButton method is used to determine whether to show/hide hamburger icon , and it is triggered every time when selecting pages.
We can define a bool field ,change its value when directing to specific pages.
FlyoutPage
public override bool ShouldShowToolbarButton()
{
return showIcon;
}
private bool showIcon = true;
private void ListView_ItemSelected(object sender, SelectedItemChangedEventArgs e)
{
var item = e.SelectedItem as FlyoutPage1FlyoutMenuItem;
if (item == null)
return;
var page = (Page)Activator.CreateInstance(item.TargetType);
page.Title = item.Title;
Detail = new NavigationPage(page);
IsPresented = false;
FlyoutPage.ListView.SelectedItem = null;
//add this logic
showIcon = (item.Id == 1) ? false : true; //only the second page do not show hamburger icon
}

Way to format Form with dynamic text fields c#

Right, so I have 13 textboxes with corresponding labels that are assigned after a user decides the name from a different form (instantiated by the 'Add field...' button). The issue arises when the user wishes to delete a textbox with previously entered data, as this results in an empty space where the textbox and label originally were as visualized by the following image:
My question is: how do I make it so that when a user chooses to delete a textbox, the textbox-label pair(s) that follow it replace the deleted textbox AND shift the remaining textboxes accordingly.
Textbox-label pairs in designer:
I've thought about this problem intensively over the past few days, and have concluded that with my current knowledge of C# I am limited to solving this issue with a horrendously tedious amount of if-statements (talking hundreds - thousands here). Any and all help would be appreciated!
Current code on the X-button for first textbox-label pair:
private void xButton1_Click(object sender, EventArgs e)
{
label14.Text = "";
textBox1.Text = "";
if (label14.Text.Equals(""))
{
label14.Visible = false;
textBox1.Visible = false;
xButton.Visible = false;
label14.Text = "";
textBox1.Text = "";
}
if (!textBox2.Text.Equals(""))
{
label14.Text = label15.Text;
textBox1.Text = textBox2.Text;
}
if (!textBox2.Text.Equals("") && (textBox3.Text.Equals("")))
{
label15.Visible = false;
textBox2.Text = "";
textBox2.Visible = false;
xButton2.Visible = false;
}
}

One simple thing you could do is give all your "dynamic" controls (label, textbox, button) a similar value in their Tag property (in my example, I used the string "dynamic" for all the control Tags. This enables you to query for them easily.
Next, you could follow the logic that, anytime you delete some controls, you move all controls below the deleted ones up a distance equal to the height of the control being deleted plus whatever padding you have between the controls.
For example, when a user clicks the X button, since you know the value of the Bottom of the control that's being deleted, you could find all controls that had a matching Tag property whose Top is greater than the x button Bottom, and you can move them up.
Here's an example (this assumes that all your X buttons are mapped to this same click event):
private void buttonX_Click(object sender, EventArgs e)
{
// This is represents the distance between the bottom
// of one control to the top of the next control
// Normally it would be defined globally, and used when you
// lay out your controls.
const int controlPadding = 6;
var xButton = sender as Button;
if (xButton == null) return;
var minTopValue = xButton.Bottom;
var distanceToMoveUp = xButton.Height + controlPadding;
// Find all controls that have the Tag and are at the same height as the button
var controlsToDelete = Controls.Cast<Control>().Where(control =>
control.Tag != null &&
control.Tag.ToString() == "dynamic" &&
control.Top == xButton.Top)
.ToList();
// Delete the controls
controlsToDelete.ForEach(Controls.Remove);
// Get all controls with the same tag that are below the deleted controls
var controlsToMove = Controls.Cast<Control>().Where(control =>
control.Tag != null &&
control.Tag.ToString() == "dynamic" &&
control.Top > minTopValue);
// Move each control up the specified amount
foreach (var controlToMove in controlsToMove)
{
controlToMove.Top -= distanceToMoveUp;
}
}

Jumping to next tab

I have a tab control in my WPF application with multiple tabs. Each tab gives access to several buttons, text boxes, drop downs. Now before moving to the next tab valid entries in each of the controls in the tab is to be checked or jumping to the next tab should not be allowed. How can this be done?
I was able to use IsEnable property to do this. But I want it like, when I click on the next tab it should, without entering the next tab, display a warning that such and such entry in the present tab is not valid.

If you adhere to the Selected event you can do something like this:
// Keep a global variable for the previous index
int prevIndex = 0;
private void tabControl_Selected(object sender, TabControlEventArgs e)
{
TabControl tc = sender as TabControl;
if (tc != null)
{
bool letSwitchHappen = validateTabControls(tc.SelectedIndex);
if (!letSwitchHappen)
{
tc.SelectedIndex = prevIndex;
}
prevIndex = tc.SelectedIndex;
}
}
Where validateTabControls is something like:
private bool validateTabControls(int tabIndex)
{
bool validEntries = false;
// Some code here to set validEntries according to the control at tabIndex
return validEntries;
}

Take a look at this example from Josh Smith.
It shows explicitly how to do this, and Josh is well-known (and respected) in the WPF world.

.NET TableLayoutPanel

Basically I have a tablelayoutpanel , it its currently being used for POS System.
When I call SetColumnSpan on a button control , the tablelayoutpanel adds an extra row, and messes up my screen layout.
Has anybody come across this before ?
Each free space in the panel is assigned a blank button, when the screen is in edit mode , they can add/edit and delete buttons.
Below is the code to apply button changes.
Edit cleaned up code a bit
void button_MouseUp(object sender, EventArgs e)
{
try
{
TableLayoutPanelCellPosition pos = tableLayoutPanel1.GetCellPosition((Control) sender);
POSButton productButton = GetProductButton(sender);
tableLayoutPanel1.SuspendLayout();
if (productButton == null)
{
DeleteButton(sender, pos);
return;
}
productButton.Dock = DockStyle.Fill;
EditModeHookButton(productButton);
tableLayoutPanel1.Controls.Remove((Control) sender);
tableLayoutPanel1.Controls.Add(productButton, pos.Column, pos.Row);
if (productButton.TableRowSpan > 0)
tableLayoutPanel1.SetRowSpan(productButton, productButton.TableRowSpan);
if (productButton.TableColumnSpan > 0)
tableLayoutPanel1.SetColumnSpan(productButton, productButton.TableColumnSpan);
buttonManager.Save(tableLayoutPanel1);
tableLayoutPanel1.ResumeLayout();
}
catch(OperationCanceledException)
{
}
}
Here is the button Manager function that serializes the button layout.
public void Save(ScreenTabkeLayoutPanel panel)
{
List<ButtonSaveInfo> buttons = new List<ButtonSaveInfo>();
foreach (Control control in panel.Controls)
{
TableLayoutPanelCellPosition pos = panel.GetCellPosition(control);
ButtonSaveInfo info;
if (control is POSButton)
info = ((POSButton)control).ConvertToButtonInfo(pos);
else
info = control.ConvertToButtonInfo(pos);
buttons.Add(info);
}
AppDataSerializer.SaveBinary(buttons,buttonPath);
}
Here is the code that loads/populates the screen with the buttons
private void LoadButtonsFromFile(ScreenTabkeLayoutPanel panel)
{
List<ButtonSaveInfo> buttons = AppDataSerializer.LoadBinary<List<ButtonSaveInfo>>(buttonPath);
panel.SuspendLayout();
foreach (ButtonSaveInfo info in buttons)
{
switch (info.ButtonType)
{
case (int) ButtonType.PRODUCT:
POSButton productButton = info.ConvertToPosButton();
wireButtonEvents(productButton);
panel.Controls.Add(productButton, info.ColumnIndex, info.RowIndex);
if (productButton.TableRowSpan > 0)
panel.SetRowSpan(productButton, productButton.TableRowSpan);
if (productButton.TableColumnSpan > 0)
panel.SetColumnSpan(productButton, productButton.TableColumnSpan);
break;
default:
Control control = BuildBlankButton();
wireButtonEvents(control);
panel.Controls.Add(control, info.ColumnIndex, info.RowIndex);
break;
}
}
FillEmptySpacesWillBlankButtons(panel);
panel.ResumeLayout();
}
Thanks in advanced.

Make sure you don't have a control in a spanned cell.
If you set column span to 2 on cell 0,0 and put a control in 1,0 this will confuse the layout engine. Since you specified in your question that you added blank buttons to all cells, this might be what is happening here.
Make sure you remove any control from a cell you are planning to span over.
Also, there are some situation in which the table layout just gives up, especially if you span cells with auto sizing.

Are you setting the RowSpan to a value greater than the number of rows in the table? This might cause an extra row to be rendered. Other than that you will need to provide more information/code for us to figure it out :)

Why is text in TextBox highlighted (selected) when form is displayed?

I have a form containing a TextBox in C# which I set to a string as follows:
textBox.Text = str;
When the form is displayed, why does the text in the texbox appear highlighted/selected?

The text box has a TabIndex of 0 and TabStop set to true. This means that the control will be given focus when the form is displayed.
You can either give another control the 0 TabIndex (if there is one) and give the text box a different tab index (>0), or set TabStop to false for the text box to stop this from happening.

The default behavior of a TextBox in Windows Forms is to highlight all of the text if it gets focused for the first time by tabbing into it, but not if it is clicked into. We can see this in Reflector by looking at the TextBox's OnGotFocus() override:
protected override void OnGotFocus(EventArgs e)
{
base.OnGotFocus(e);
if (!this.selectionSet)
{
this.selectionSet = true;
if ((this.SelectionLength == 0) && (Control.MouseButtons == MouseButtons.None))
{
base.SelectAll();
}
}
}
It's that if statement that is causing the behavior that we don't like. Furthermore, to add insult to injury, the Text property's setter blindly resets that selectionSet variable whenever the text is re-assigned:
public override string Text
{
get
{
return base.Text;
}
set
{
base.Text = value;
this.selectionSet = false;
}
}
So if you have a TextBox and tab into it, all the text will be selected. If you click into it, the highlight is removed, and if you re-tab into it, your caret position (and selection length of zero) is preserved. But if we programmatically set new Text, and tab into the TextBox again, then all of the text will be selected again.
If you are like me and find this behavior annoying and inconsistent, then there are two ways around this problem.
The first, and probably the easiest, is to simply trigger the setting of selectionSet by calling DeselectAll() on form Load() and whenever the Text changes:
protected override void OnLoad(EventArgs e)
{
base.OnLoad(e);
this.textBox2.SelectionStart = this.textBox2.Text.Length;
this.textBox2.DeselectAll();
}
(DeselectAll() just sets SelectionLength to zero. It's actually SelectionStart that flips the TextBox's selectionSet variable. In the above case, the call to DeselectAll() is not necessary since we are setting the start to the end of the text. But if we set it to any other position, like the start of the text, then calling it is a good idea.)
The more permanent way is to create our own TextBox with the desired behavior through inheritance:
public class NonSelectingTextBox : TextBox
{
// Base class has a selectionSet property, but its private.
// We need to shadow with our own variable. If true, this means
// "don't mess with the selection, the user did it."
private bool selectionSet;
protected override void OnGotFocus(EventArgs e)
{
bool needToDeselect = false;
// We don't want to avoid calling the base implementation
// completely. We mirror the logic that we are trying to avoid;
// if the base implementation will select all of the text, we
// set a boolean.
if (!this.selectionSet)
{
this.selectionSet = true;
if ((this.SelectionLength == 0) &&
(Control.MouseButtons == MouseButtons.None))
{
needToDeselect = true;
}
}
// Call the base implementation
base.OnGotFocus(e);
// Did we notice that the text was selected automatically? Let's
// de-select it and put the caret at the end.
if (needToDeselect)
{
this.SelectionStart = this.Text.Length;
this.DeselectAll();
}
}
public override string Text
{
get
{
return base.Text;
}
set
{
base.Text = value;
// Update our copy of the variable since the
// base implementation will have flipped its back.
this.selectionSet = false;
}
}
}
You maybe tempted to just not call base.OnGotFocus(), but then we would lose useful functionality in the base Control class. And you might be tempted to not mess with the selectionSet nonsense at all and simply deselect the text every time in OnGotFocus(), but then we would lose the user's highlight if they tabbed out of the field and back.
Ugly? You betcha. But it is what it is.

The answers to this question helped me a lot with a similar problem, but the simple answer is only hinted at with a lot of other complex suggestions. Just set SelectionStart to 0 after setting your Text. Problem solved!
Example:
yourtextbox.Text = "asdf";
yourtextbox.SelectionStart = 0;

You can also choose the tab order for your form's controls by opening:
View->Tab Order
Note that this option is only available in "View" if you have the Form design view open.
Selecting "Tab Order" opens a view of the Form which allows you to choose the desired tab order by clicking on the controls.

To unhighlight a text field, with VS 2013, try init with:
myTextBox.GotFocus += new System.EventHandler(this.myTextBox_GotFocus);
And add the method:
public void myTextBox_GotFocus(object sender, EventArgs e)
{
myTextBox.SelectionLength=0;
}

I haven't tested this on C# but I ran into the same issue using a C++ WIN32 dialog box. Is seems like you can change the behavior by returning FALSE from OnInitDialog() or WM_INITDIALOG. Hope this helps.

Here is what worked for me
public void SetNotes(string notes)
{
notesTextBox.Text = notes;
notesTextBox.Select();
notesTextBox.SelectionLength = 0;
notesTextBox.SelectionStart = notes.Length;//place cursor at end of text
}