Bug 473081 - Scroll lock enables on empty console
Change-Id: Ida07a9a1921361c3b040a9222f233ed58cde2f54
diff --git a/org.eclipse.ui.console/src/org/eclipse/ui/console/TextConsoleViewer.java b/org.eclipse.ui.console/src/org/eclipse/ui/console/TextConsoleViewer.java
index fdfffe1..f1fbae3 100644
--- a/org.eclipse.ui.console/src/org/eclipse/ui/console/TextConsoleViewer.java
+++ b/org.eclipse.ui.console/src/org/eclipse/ui/console/TextConsoleViewer.java
@@ -1,5 +1,5 @@
/*******************************************************************************
- * Copyright (c) 2000, 2017 IBM Corporation and others.
+ * Copyright (c) 2000, 2018 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
@@ -151,7 +151,9 @@
}
}
- // set the scroll Lock setting for Console Viewer and Console View
+ /*
+ * Checks if at the end of document
+ */
private boolean checkEndOfDocument() {
StyledText textWidget = getTextWidget();
if (textWidget != null && !textWidget.isDisposed()) {
@@ -163,10 +165,28 @@
return false;
}
+ /*
+ * Check if the document is empty or the line count is smaller than each
+ * vertical scroll
+ */
private boolean isEmptyDocument() {
StyledText textWidget = getTextWidget();
if (textWidget != null && !textWidget.isDisposed()) {
- return (textWidget.getLineCount() <= 1);
+ return (textWidget.getLineCount() <= textWidget.getVerticalBar().getIncrement());
+ }
+ return false;
+ }
+
+ /*
+ * Checks if at the start of document
+ */
+ private boolean checkStartOfDocument() {
+ StyledText textWidget = getTextWidget();
+ if (textWidget != null && !textWidget.isDisposed()) {
+ int partialTopIndex = JFaceTextUtil.getPartialTopIndex(textWidget);
+ int lineCount = textWidget.getLineCount();
+ int delta = textWidget.getVerticalBar().getIncrement();
+ return lineCount - partialTopIndex < delta;
}
return false;
}
@@ -234,6 +254,9 @@
styledText.getVerticalBar().addSelectionListener(new SelectionAdapter() {
@Override
public void widgetSelected(SelectionEvent e) {
+ if (isEmptyDocument()) {
+ return;
+ }
// scroll lock if vertical scroll bar dragged, OR selection on
// vertical bar used
if (e.detail == SWT.TOP || e.detail == SWT.HOME) {
@@ -241,11 +264,7 @@
setScrollLock(true);
}
if (e.detail == SWT.ARROW_UP || e.detail == SWT.PAGE_UP) {
- if (isEmptyDocument()) {
- setScrollLock(false);
- } else {
- setScrollLock(true);
- }
+ setScrollLock(true);
} else if (e.detail == SWT.END || e.detail == SWT.BOTTOM) {
// selecting BOTTOM or END from vertical scroll makes it
// reveal the end
@@ -265,16 +284,14 @@
styledText.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent e) {
+ if (isEmptyDocument()) {
+ return;
+ }
// lock the scroll if PAGE_UP ,HOME or TOP selected
if (e.keyCode == SWT.HOME || e.keyCode == SWT.TOP) {
setScrollLock(true);
- } else if ((e.keyCode == SWT.PAGE_UP || e.keyCode == SWT.ARROW_UP)) {
- if (isEmptyDocument()) {
- setScrollLock(false);
- } else {
- setScrollLock(true);
- }
-
+ } else if ((e.keyCode == SWT.PAGE_UP || e.keyCode == SWT.ARROW_UP) && !checkStartOfDocument()) {
+ setScrollLock(true);
} else if (e.keyCode == SWT.END || e.keyCode == SWT.BOTTOM) {
setScrollLock(false);// selecting END makes it reveal the
// end
@@ -287,16 +304,15 @@
styledText.addMouseWheelListener(new MouseWheelListener() {
@Override
public void mouseScrolled(MouseEvent e) {
+ if (isEmptyDocument()) {
+ return;
+ }
if (e.count < 0) { // Mouse dragged down
if (checkEndOfDocument()) {
setScrollLock(false);
}
} else if (!userHoldsScrollLock.get()) {
- if (isEmptyDocument()) {
- setScrollLock(false);
- } else {
- setScrollLock(true);
- }
+ setScrollLock(true);
}
}
});
