I have the following element:
-
I know this is an old topic but this may help someone else.
I was able to make the body scroll by making the modal-dialog element position fixed. And since I would never know the exact height of the browser window, I took the information I was sure about, the height of the header and the footer. I was then able to make the modal-body element's top and bottom margins match those heights. This then produced the result I was looking for. I threw together a fiddle to show my work.
also, if you want a full screen dialog just un-comment the width:auto; inside the .modal-dialog.full-screen section.
https://jsfiddle.net/lot224/znrktLej/
And here is the css that I used to modify the bootstrap dialog.
.modal-dialog.full-screen {
position:fixed;
//width:auto; // uncomment to make the width based on the left/right attributes.
margin:auto;
left:0px;
right:0px;
top:0px;
bottom:0px;
}
.modal-dialog.full-screen .modal-content {
position:absolute;
left:10px;
right:10px;
top:10px;
bottom:10px;
}
.modal-dialog.full-screen .modal-content .modal-header {
height:55px; // adjust as needed.
}
.modal-dialog.full-screen .modal-content .modal-body {
overflow-y: auto;
position: absolute;
top: 0;
bottom: 0;
left:0;
right:0;
margin-top: 55px; // .modal-header height
margin-bottom: 80px; // .modal-footer height
}
.modal-dialog.full-screen .modal-content .modal-footer {
height:80px; // adjust as needed.
position:absolute;
bottom:0;
left:0;
right:0;
}