TreeView: Add rootIndex property

Its purpose is the same as QAbstractItemView::rootIndex
and allows to display only the part of the model data that
is descendant of this index.

The filesystembrowser example has been updated to only show
files reachable from the user's home directory.

[ChangeLog][TreeView] Added rootIndex property

Change-Id: Ib8d9af4ce9d1f341ab509de3cc991773830ba9f4
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@theqtcompany.com>
Reviewed-by: Mitch Curtis <mitch.curtis@theqtcompany.com>

1 files changed, 42 insertions, 5 deletions

diff --git a/tests/auto/qquicktreemodeladaptor/tst_qquicktreemodeladaptor.cpp b/tests/auto/qquicktreemodeladaptor/tst_qquicktreemodeladaptor.cpp
index b484665d..13a92ea7 100644
--- a/tests/auto/qquicktreemodeladaptor/tst_qquicktreemodeladaptor.cpp
+++ b/tests/auto/qquicktreemodeladaptor/tst_qquicktreemodeladaptor.cpp
@@ -57,6 +57,8 @@ private slots:
     void modelDestroyed();
     void modelReset();
 
+    void rootIndex();
+
     void dataAccess();
     void dataChange();
     void groupedDataChange();
@@ -96,9 +98,10 @@ void tst_QQuickTreeModelAdaptor::cleanup()
 void tst_QQuickTreeModelAdaptor::compareData(int row, QQuickTreeModelAdaptor &tma, const QModelIndex &modelIdx, TestModel &model, bool expanded)
 {
     const QModelIndex &tmaIdx = tma.index(row);
+    const int indexDepth = model.level(modelIdx) - model.level(tma.rootIndex()) - 1;
     QCOMPARE(tma.mapToModel(tmaIdx), modelIdx);
     QCOMPARE(tma.data(tmaIdx, Qt::DisplayRole).toString(), model.displayData(modelIdx));
-    QCOMPARE(tma.data(tmaIdx, QQuickTreeModelAdaptor::DepthRole).toInt(), model.level(modelIdx));
+    QCOMPARE(tma.data(tmaIdx, QQuickTreeModelAdaptor::DepthRole).toInt(), indexDepth);
     QCOMPARE(tma.data(tmaIdx, QQuickTreeModelAdaptor::ExpandedRole).toBool(), expanded);
     QCOMPARE(tma.data(tmaIdx, QQuickTreeModelAdaptor::HasChildrenRole).toBool(), model.hasChildren(modelIdx));
 }
@@ -117,7 +120,7 @@ void tst_QQuickTreeModelAdaptor::expandAndTest(const QModelIndex &idx, QQuickTre
     const QModelIndex &tmaIdx = tma.index(tma.itemIndex(idx));
     QCOMPARE(tma.data(tmaIdx, QQuickTreeModelAdaptor::ExpandedRole).toBool(), expandable);
 
-    if (expandable) {
+    if (expandable && expectedRowCountDifference != 0) {
         // Rows were added below the parent
         QCOMPARE(tma.rowCount(), oldRowCount + expectedRowCountDifference);
         QCOMPARE(rowsAboutToBeInsertedSpy.count(), rowsInsertedSpy.count());
@@ -160,7 +163,7 @@ void tst_QQuickTreeModelAdaptor::collapseAndTest(const QModelIndex &idx, QQuickT
     if (tmaIdx.isValid())
         QCOMPARE(tma.data(tmaIdx, QQuickTreeModelAdaptor::ExpandedRole).toBool(), false);
 
-    if (expandable) {
+    if (expandable && expectedRowCountDifference != 0) {
         // Rows were removed below the parent
         QCOMPARE(tma.rowCount(), oldRowCount - expectedRowCountDifference);
         QCOMPARE(rowsAboutToBeRemovedSpy.count(), 1);
@@ -188,9 +191,9 @@ void tst_QQuickTreeModelAdaptor::collapseAndTest(const QModelIndex &idx, QQuickT
 
 void tst_QQuickTreeModelAdaptor::compareModels(QQuickTreeModelAdaptor &tma, TestModel &model)
 {
-    QModelIndex parent;
+    QModelIndex parent = tma.rootIndex();
     QStack<QModelIndex> parents;
-    QModelIndex idx = model.index(0, 0);
+    QModelIndex idx = model.index(0, 0, parent);
     int modelVisibleRows = model.rowCount(parent);
     for (int i = 0; i < tma.rowCount(); i++) {
         bool expanded = tma.isExpanded(i);
@@ -283,6 +286,40 @@ void tst_QQuickTreeModelAdaptor::modelReset()
     compareModels(tma, model);
 }
 
+void tst_QQuickTreeModelAdaptor::rootIndex()
+{
+    TestModel model(5, 1);
+
+    QQuickTreeModelAdaptor tma;
+    tma.setModel(&model);
+
+    QVERIFY(!tma.rootIndex().isValid());
+    compareModels(tma, model);
+
+    QSignalSpy rootIndexSpy(&tma, SIGNAL(rootIndexChanged()));
+    QModelIndex rootIndex = model.index(0, 0);
+    tma.setRootIndex(rootIndex);
+    QCOMPARE(tma.rootIndex(), rootIndex);
+    QCOMPARE(rootIndexSpy.count(), 1);
+    compareModels(tma, model);
+
+    rootIndexSpy.clear();
+    rootIndex = model.index(2, 2, tma.rootIndex());
+    tma.setRootIndex(rootIndex);
+    QCOMPARE(tma.rootIndex(), rootIndex);
+    QCOMPARE(rootIndexSpy.count(), 1);
+    compareModels(tma, model);
+
+    // Expand 1st visible item, business as usual
+    expandAndTest(model.index(0, 0, rootIndex), tma, true /*expandable*/, 5);
+    // Expand non root item descendant item, nothing should happen
+    expandAndTest(model.index(0, 0), tma, true /*expandable*/, 0);
+    // Collapse 1st visible item, business as usual
+    collapseAndTest(model.index(0, 0, rootIndex), tma, true /*expandable*/, 5);
+    // Collapse non root item descendant item, nothing should happen
+    collapseAndTest(model.index(0, 0), tma, true /*expandable*/, 0);
+}
+
 void tst_QQuickTreeModelAdaptor::dataAccess()
 {
     TestModel model(5, 1);