Visual Studio complains: Warning 1 The designer must create an instance of type 'RentalEase.CustomBindingNavForm' but it cannot because the type is declared as abstract.
Visual Studio won't let me access the Designer for the form. The class already implements all abstract methods from the CustomBindingNavForm. CustomBindingNavForm provides some functions concrete and abstract.
Is there a way around this?
Here is the class:
public abstract class CustomBindingNavForm : SingleInstanceForm {
//Flags for managing BindingSource
protected bool isNew = false;
protected bool isUpdating = false;
/// <summary>
/// This is so that when a new item is added, it sets isNew and firstPass to true. The Position Changed Event will look for
/// firstPass and if it is true set it to false. Then on the next pass, it will see it's false and set isNew to false.
/// This is needed because the Position Changed Event will fire when a new item is added.
/// </summary>
protected bool firstPass = false;
protected abstract bool validateInput();
protected abstract void saveToDatabase();
//manipulating binding
protected abstract void bindingSourceCancelResetCurrent();
protected abstract void bindingSourceRemoveCurrent();
protected abstract void bindingSourceMoveFirst();
protected abstract void bindingSourceMoveNext();
protected abstract void bindingSourceMoveLast();
protected abstract void bindingSourceMovePrevious();
protected abstract void bindingSourceAddNew();
public void bindingNavigatorMovePreviousItem_Click(object sender, EventArgs e) {
if (validateInput()) {
bindingSourceMovePrevious();
} else {
DialogResult cont = MessageBox.Show(null, "There are errors in your data. Click Cancel to go back and fix them, or ok to continue. If you continue, changes will not be saved.", "Continue?", MessageBoxButtons.OKCancel, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2);
if (cont == DialogResult.OK) {
if (isNew) {
bindingSourceRemoveCurrent();
isNew = false;
} else {
bindingSourceCancelResetCurrent();
bindingSourceMovePrevious();
}
}
}
}
public void bindingNavigatorAddNewItem_Click(object sender, EventArgs e) {
if (validateInput()) {
saveToDatabase();
bool temp = isUpdating;
isUpdating = true;
bindingSourceAddNew();
isUpdating = temp;
isNew = true;
firstPass = true;
} else {
DialogResult cont = MessageBox.Show(null, "There are errors in your data. Click Cancel to go back and fix them, or ok to continue. If you continue, changes will not be saved.", "Continue?", MessageBoxButtons.OKCancel, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2);
if (cont == DialogResult.OK) {
if (isNew) {
bindingSourceRemoveCurrent();
isNew = false;
} else {
bindingSourceCancelResetCurrent();
}
bool temp = isUpdating;
isUpdating = true;
bindingSourceAddNew();
isUpdating = temp;
isNew = true;
firstPass = true;
}
}
}
public void bindingNavigatorMoveFirstItem_Click(object sender, EventArgs e) {
if (validateInput()) {
bindingSourceMoveFirst();
} else {
DialogResult cont = MessageBox.Show(null, "There are errors in your data. Click Cancel to go back and fix them, or ok to continue. If you continue, changes will not be saved.", "Continue?", MessageBoxButtons.OKCancel, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2);
if (cont == DialogResult.OK) {
if (isNew) {
bindingSourceRemoveCurrent();
isNew = false;
} else {
bindingSourceCancelResetCurrent();
}
bindingSourceMoveFirst();
}
}
}
public void bindingNavigatorMoveNextItem_Click(object sender, EventArgs e) {
if (validateInput()) {
bindingSourceMoveNext();
} else {
DialogResult cont = MessageBox.Show(null, "There are errors in your data. Click Cancel to go back and fix them, or ok to continue. If you continue, changes will not be saved.", "Continue?", MessageBoxButtons.OKCancel, MessageBoxIcon.Question, MessageBoxDefaultButton.Button2);
if (cont == DialogResult.OK) {
if (isNew) {
bindingSourceRemoveCurrent();
isNew = false;
} else {
bindingSourceCancelResetCurrent();
}
bindingSourceMoveNext();
}
}
}
}