add jumpToPage API to PageView.

1. This commit also fix the default font size issue in ui::Button.

cocos/ui/UIButton.cpp

@@ -767,6 +767,7 @@ void Button::setTitleText(const std::string& text)
         this->createTitleRenderer();
     }
     _titleRenderer->setString(text);
+    this->setTitleFontSize(_fontSize);
     updateContentSize();
 }
 

cocos/ui/UIPageView.cpp

@@ -259,6 +259,15 @@ void PageView::updateAllPagesPosition()
     }
 }
 
+void PageView::setCurPageIndex( ssize_t index )
+{
+    if (index < 0 || index >= this->getPageCount())
+    {
+        return;
+    }
+    _curPageIdx = index;
+    _doLayoutDirty = true;
+}
 
 void PageView::scrollToPage(ssize_t idx)
 {

cocos/ui/UIPageView.h

@@ -151,16 +151,24 @@ public:
     /**
      * Scroll to a page with a given index.
      *
-     * @param idx   A given index in the PageView.
+     * @param idx   A given index in the PageView. Index start from 0 to pageCount -1.
      */
     void scrollToPage(ssize_t idx);
 
+
     /**
      * Gets current displayed page index.
      * @return current page index.
      */
     ssize_t getCurPageIndex() const;
 
+    /**
+     * Jump to a page with a given index without scrolling.
+     * This is the different between scrollToPage.
+     *
+     * @param index A given index in PageView. Index start from 0 to pageCount -1.
+     */
+    void setCurPageIndex(ssize_t index);
      
     /**
      * @brief Get all the pages in the PageView.

tests/cpp-tests/Classes/UITest/CocoStudioGUITest/UIPageViewTest/UIPageViewTest.cpp

@@ -11,6 +11,7 @@ UIPageViewTests::UIPageViewTests()
     ADD_TEST_CASE(UIPageViewCustomScrollThreshold);
     ADD_TEST_CASE(UIPageViewTouchPropagationTest);
     ADD_TEST_CASE(UIPageViewDynamicAddAndRemoveTest);
+    ADD_TEST_CASE(UIPageViewJumpToPageTest);
 }
 
 // UIPageViewTest
@@ -691,3 +692,114 @@ void UIPageViewDynamicAddAndRemoveTest::pageViewEvent(Ref *pSender, PageView::Ev
     }
 }
 
+
+// UIPageViewJumpToPageTest
+UIPageViewJumpToPageTest::UIPageViewJumpToPageTest()
+: _displayValueLabel(nullptr)
+{
+
+}
+
+UIPageViewJumpToPageTest::~UIPageViewJumpToPageTest()
+{
+}
+
+bool UIPageViewJumpToPageTest::init()
+{
+    if (UIScene::init())
+    {
+        Size widgetSize = _widget->getContentSize();
+
+        // Add a label in which the dragpanel events will be displayed
+        _displayValueLabel = Text::create("setCurPageIndex API Test", "fonts/Marker Felt.ttf", 32);
+        _displayValueLabel->setAnchorPoint(Vec2(0.5f, -1.0f));
+        _displayValueLabel->setPosition(Vec2(widgetSize.width / 2.0f,
+                                              widgetSize.height / 2.0f +
+                                              _displayValueLabel->getContentSize().height * 1.5));
+        _uiLayer->addChild(_displayValueLabel);
+
+        // Add the black background
+        Text* alert = Text::create("PageView", "fonts/Marker Felt.ttf", 30);
+        alert->setColor(Color3B(159, 168, 176));
+        alert->setPosition(Vec2(widgetSize.width / 2.0f, widgetSize.height / 2.0f - alert->getContentSize().height * 3.075f));
+        _uiLayer->addChild(alert);
+
+        Layout* root = static_cast<Layout*>(_uiLayer->getChildByTag(81));
+
+        Layout* background = dynamic_cast<Layout*>(root->getChildByName("background_Panel"));
+
+        // Create the page view
+        PageView* pageView = PageView::create();
+        pageView->setContentSize(Size(240.0f, 130.0f));
+        Size backgroundSize = background->getContentSize();
+        pageView->setPosition(Vec2((widgetSize.width - backgroundSize.width) / 2.0f +
+                                  (backgroundSize.width - pageView->getContentSize().width) / 2.0f,
+                                  (widgetSize.height - backgroundSize.height) / 2.0f +
+                                  (backgroundSize.height - pageView->getContentSize().height) / 2.0f));
+
+        pageView->removeAllPages();
+
+        int pageCount = 4;
+        for (int i = 0; i < pageCount; ++i)
+        {
+            Layout* layout = Layout::create();
+            layout->setContentSize(Size(240.0f, 130.0f));
+
+            ImageView* imageView = ImageView::create("cocosui/scrollviewbg.png");
+            imageView->setScale9Enabled(true);
+            imageView->setContentSize(Size(240, 130));
+            imageView->setPosition(Vec2(layout->getContentSize().width / 2.0f, layout->getContentSize().height / 2.0f));
+            layout->addChild(imageView);
+
+            Text* label = Text::create(StringUtils::format("page %d",(i+1)), "fonts/Marker Felt.ttf", 30);
+            label->setColor(Color3B(192, 192, 192));
+            label->setPosition(Vec2(layout->getContentSize().width / 2.0f, layout->getContentSize().height / 2.0f));
+            layout->addChild(label);
+
+            pageView->insertPage(layout,i);
+        }
+
+        pageView->setCurPageIndex(1);
+
+        //add buttons to jump to specific page
+        auto button1 = ui::Button::create();
+        button1->setNormalizedPosition(Vec2(0.1, 0.75));
+        button1->setTitleText("Jump to Page1");
+        CCLOG("button1 content Size = %f, %f", button1->getContentSize().width,
+              button1->getContentSize().height);
+        button1->addClickEventListener([=](Ref*){
+            pageView->setCurPageIndex(0);
+        });
+        _uiLayer->addChild(button1);
+
+        auto button2 = static_cast<ui::Button*>(button1->clone());
+        button2->setTitleText("Jump to Page2");
+        button2->setNormalizedPosition(Vec2(0.1, 0.65));
+        CCLOG("button2 content Size = %f, %f", button2->getContentSize().width,
+              button2->getContentSize().height);
+        button2->addClickEventListener([=](Ref*){
+            pageView->setCurPageIndex(1);
+        });
+        _uiLayer->addChild(button2);
+
+        auto button3 = static_cast<ui::Button*>(button2->clone());
+        button3->setTitleText("Jump to Page3");
+        button3->setNormalizedPosition(Vec2(0.9, 0.75));
+        button3->addClickEventListener([=](Ref*){
+            pageView->setCurPageIndex(2);
+        });
+        _uiLayer->addChild(button3);
+
+        auto button4 = static_cast<ui::Button*>(button2->clone());
+        button4->setTitleText("Jump to Page4");
+        button4->setNormalizedPosition(Vec2(0.9, 0.65));
+        button4->addClickEventListener([=](Ref*){
+            pageView->setCurPageIndex(3);
+        });
+        _uiLayer->addChild(button4);
+        _uiLayer->addChild(pageView);
+
+        return true;
+    }
+    return false;
+}

tests/cpp-tests/Classes/UITest/CocoStudioGUITest/UIPageViewTest/UIPageViewTest.h

@@ -112,4 +112,18 @@ protected:
     cocos2d::ui::Text* _displayValueLabel;
 };
 
+class UIPageViewJumpToPageTest : public UIScene
+{
+public:
+    CREATE_FUNC(UIPageViewJumpToPageTest);
+
+    UIPageViewJumpToPageTest();
+    ~UIPageViewJumpToPageTest();
+    virtual bool init() override;
+
+protected:
+
+    cocos2d::ui::Text* _displayValueLabel;
+};
+
 #endif /* defined(__TestCpp__UIPageViewTest__) */