blob: 0174054a08c3fbab4415464c7cc29e194c101bed (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
|
/*******************************************************************************
* Copyright (c) 2005, 2011 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
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.debug.internal.ui.viewers.model.provisional;
import org.eclipse.jface.viewers.ISelection;
/**
* Resolves selection conflicts within a model. When
* a selection exists in a viewer, and a client asks
* to set another selection, the selection policy for
* that model is asked to determine whether the new
* selection should override the previous selection.
* When a selection is from a different model, the
* original selection is maintained if its model selection
* policy specifies the selection to be 'sticky'.
* <p>
* A selection policy is obtained by querying for the selection
* policy factory for a given element. The selection policy factory
* will then be asked to create a model selection policy adapter.
* The adapter represents selections from an instance of a model.
* </p>
*
* @see IModelSelectionPolicyFactory
* @since 3.2
*/
public interface IModelSelectionPolicy {
/**
* Returns whether the given selection is contained in this model.
*
* @param selection Selection to check
* @param context Presentation context of the viewer.
* @return true if selection is contained in model.
*/
public boolean contains(ISelection selection, IPresentationContext context);
/**
* Returns whether the candidate selection overrides the
* existing selection. The policy is only asked about selections
* that it contains.
*
* @param existing Existing selection to check.
* @param candidate New proposed selection.
* @param context Presentation context of viewer.
* @return true if candidate selection should be set to viewer
*/
public boolean overrides(ISelection existing, ISelection candidate, IPresentationContext context);
/**
* Returns whether the given selection should be maintained in the
* face of a selection attempt from a different model.
*
* @param selection selection to test
* @param context Presentation context of viewer.
* @return true if selection is sticky
*/
public boolean isSticky(ISelection selection, IPresentationContext context);
/**
* Replaces an invalid selection.
* <p>
* This method is called if a model change picked up by a viewer
* results in an invalid selection. For instance if an element contained in
* the selection has been removed from the viewer, the selection policy associated
* with the invalid selection is free to specify a new selection. The default
* selection policy returns the <code>newSelection</code> as is (with missing
* elements removed). Model selection policies may implement a different strategy
* for picking a new selection when the old selection becomes invalid.
* </p>
*
* @param invalidSelection
* the selection before the viewer was updated
* @param newSelection
* the selection after the update, or <code>null</code> if none
* @return new selection or <code>null</code> if none
*/
public ISelection replaceInvalidSelection(ISelection invalidSelection, ISelection newSelection);
}
|
