Add support of invoking QFuture continuations in a given context

Added overloads of .then()/.onFailed()/.onCanceled() which take a
pointer of a context object, and invoke the continuations in the
object's thread.

Task-number: QTBUG-86794
Change-Id: I0f3cbb0500695673fc4087af5d4b96b416e3e1ce
Reviewed-by: Andrei Golubev <andrei.golubev@qt.io>
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Leena Miettinen <riitta-leena.miettinen@qt.io>

1 files changed, 31 insertions, 0 deletions

diff --git a/src/corelib/doc/snippets/code/src_corelib_thread_qfuture.cpp b/src/corelib/doc/snippets/code/src_corelib_thread_qfuture.cpp
index da17b390fd..a5e1a7f6e4 100644
--- a/src/corelib/doc/snippets/code/src_corelib_thread_qfuture.cpp
+++ b/src/corelib/doc/snippets/code/src_corelib_thread_qfuture.cpp
@@ -252,3 +252,34 @@ auto resultFuture = testFuture.then([](int res) {
     // Block 6
 });
 //! [16]
+
+//! [17]
+// somewhere in the main thread
+auto future = QtConcurrent::run([] {
+    // This will run in a separate thread
+    ...
+}).then(this, [] {
+   // Update UI elements
+});
+//! [17]
+
+//! [18]
+auto future = QtConcurrent::run([] {
+    ...
+}).then(this, [] {
+   // Update UI elements
+}).then([] {
+    // This will also run in the main thread
+});
+//! [18]
+
+//! [19]
+// somewhere in the main thread
+auto future = QtConcurrent::run([] {
+    // This will run in a separate thread
+    ...
+    throw std::exception();
+}).onFailed(this, [] {
+   // Update UI elements
+});
+//! [19]