From 4e60681c879a54cf5b34862a30e27c492ed36363 Mon Sep 17 00:00:00 2001 From: Assam Boudjelthia Date: Thu, 14 Jan 2021 12:38:04 +0200 Subject: Make QJniObject and QJniEnvironment public API As part of Qt 6 restructring for the extras modules, this change exposes the Jni APIs which are very important for Android platform. This patch adds the APIs QJniObject, QJniEnvironment, QJniExceptionCleaner based from private QtCore and QtAndroidExtras. The Jni interface is cross-platform which justifies the name, but currently, this API is used mainly for Android, and the naming comes generic without Android keyword to avoid any future limitation on supporting other platforms. [ChangeLog][QtCore] Add new QJniObject, QJniEnvironment and QJniExceptionCleaner APIs. Task-number: QTBUG-89482 Fixes: QTBUG-89633 Change-Id: I4382dd53a225375759b9d042f6035a4a9810572b Reviewed-by: Ville Voutilainen --- src/corelib/doc/snippets/jni/src_qjniobject.cpp | 133 ++++++++++++++++++++++++ 1 file changed, 133 insertions(+) create mode 100644 src/corelib/doc/snippets/jni/src_qjniobject.cpp (limited to 'src/corelib/doc') diff --git a/src/corelib/doc/snippets/jni/src_qjniobject.cpp b/src/corelib/doc/snippets/jni/src_qjniobject.cpp new file mode 100644 index 0000000000..f3433134db --- /dev/null +++ b/src/corelib/doc/snippets/jni/src_qjniobject.cpp @@ -0,0 +1,133 @@ +/**************************************************************************** + ** + ** Copyright (C) 2021 The Qt Company Ltd. + ** Contact: http://www.qt.io/licensing/ + ** + ** This file is part of the documentation of the Qt Toolkit. + ** + ** $QT_BEGIN_LICENSE:BSD$ + ** Commercial License Usage + ** Licensees holding valid commercial Qt licenses may use this file in + ** accordance with the commercial license agreement provided with the + ** Software or, alternatively, in accordance with the terms contained in + ** a written agreement between you and The Qt Company. 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IN NO EVENT SHALL THE COPYRIGHT + ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE." + ** + ** $QT_END_LICENSE$ + ** + ****************************************************************************/ + +//! [Working with lists] +QStringList getTrackTitles(const QJniObject &album) { + QStringList stringList; + QJniObject list = album.callObjectMethod("getTitles", + "()Ljava/util/List;"); + + if (list.isValid()) { + const int size = list.callMethod("size"); + for (int i = 0; i < size; ++i) { + QJniObject title = list.callObjectMethod("get", "(I)Ljava/lang/Object;", i); + stringList.append(title.toString()); + } + } + return stringList; +} +//! [Working with lists] + +//! [QJniObject scope] +void functionScope() +{ + QString helloString("Hello"); + jstring myJString = 0; + { + QJniObject string = QJniObject::fromString(helloString); + myJString = string.object(); + } + + // Ops! myJString is no longer valid. +} +//! [QJniObject scope] + +//! [Registering native methods] +static void fromJavaOne(JNIEnv *env, jobject thiz, jint x) +{ + Q_UNUSED(env); + Q_UNUSED(thiz); + qDebug() << x << "< 100"; +} + +static void fromJavaTwo(JNIEnv *env, jobject thiz, jint x) +{ + Q_UNUSED(env); + Q_UNUSED(thiz); + qDebug() << x << ">= 100"; +} + +void registerNativeMethods() { + JNINativeMethod methods[] {{"callNativeOne", "(I)V", reinterpret_cast(fromJavaOne)}, + {"callNativeTwo", "(I)V", reinterpret_cast(fromJavaTwo)}}; + + QJniObject javaClass("my/java/project/FooJavaClass"); + QJniEnvironment env; + jclass objectClass = env->GetObjectClass(javaClass.object()); + env->RegisterNatives(objectClass, + methods, + sizeof(methods) / sizeof(methods[0])); + env->DeleteLocalRef(objectClass); +} + +void foo() +{ + QJniObject::callStaticMethod("my/java/project/FooJavaClass", "foo", "(I)V", 10); // Output: 10 < 100 + QJniObject::callStaticMethod("my/java/project/FooJavaClass", "foo", "(I)V", 100); // Output: 100 >= 100 +} + +//! [Registering native methods] + +//! [Java native methods] +class FooJavaClass +{ + public static void foo(int x) + { + if (x < 100) + callNativeOne(x); + else + callNativeTwo(x); + } + +private static native void callNativeOne(int x); +private static native void callNativeTwo(int x); + +} +//! [Java native methods] -- cgit v1.2.3