Modifying scrolling behavior with competing constraint priorities in landscape and portrait modes

A system comprising:

• a display screen;
• a data repository connected to the display screen and storing:
• a modal dialog displayable on a display screen of a device, the modal dialog having a modal dialog height, and the modal dialog further comprising a first section and a content section having a content section height,
• a first scrolling frame defined for the modal dialog and defining a first scrolling behavior of the modal dialog,
• a second scrolling frame defined for the modal dialog and defining a second scrolling behavior of the modal dialog,
• a first constraint defined for the first scrolling frame,
• a second constraint defined for the second scrolling frame,
• a first priority and a second priority assignable to the first constraint,
• an applicable priority comprising one of the first priority and the second priority,
• a third priority assigned to the second constraint, and
• a determination of whether the display screen is in the portrait orientation or in the landscape orientation;
• and
• a controller connected to the data repository and configured to perform, in response to receiving a command to display the modal dialog:
• generating the determination of whether the display screen is in the portrait orientation or in the landscape orientation,
• assigning, based on the determination, one of the first priority and the second priority as the applicable priority, and
• displaying, on the display screen, the modal dialog.

A method of programmatically controlling scrolling behavior of a modal dialog when the modal dialog is displayed on a display screen of a device, comprising:

• establishing a first scrolling frame for the modal dialog, the first scrolling frame having a first constraint and defining a first scrolling behavior of the modal dialog;
• establishing a second scrolling frame for the modal dialog, the second scrolling frame having a second constraint and defining a second scrolling behavior of the modal dialog, wherein the second scrolling frame is nested with respect to the first scrolling frame;
• establishing a first priority for the first constraint when the display screen is in a portrait orientation;
• establishing a second priority for the first constraint when the display screen is in a landscape orientation;
• establishing a third priority for the second constraint, wherein the third priority is less than the first priority, and wherein the second priority is less than the third priority;
• and
• programmatically generating a command to change an applicable priority of the first constraint between the first priority and the second priority, responsive to detection of a change in orientation of the display screen between the portrait orientation and the landscape orientation.