Java JViewport.getExtentSize方法代码示例

import javax.swing.JViewport; //导入方法依赖的package包/类
private void changed() {
    JViewport viewport = sp.getViewport();
    Point viewPosition = viewport.getViewPosition();
    if (viewPosition.x > 0) {
        try {
            Rectangle textRect = editorPane.getUI().modelToView(editorPane, editorPane.getDocument().getLength());
            int textLength = textRect.x + textRect.width;
            int viewLength = viewport.getExtentSize().width;
            //System.out.println("Utilities.createSingleLineEditor(): spLength = "+sp.getSize().width+", viewLength = "+viewLength+", textLength = "+textLength+", viewPosition = "+viewPosition);
            if (textLength < (viewPosition.x + viewLength)) {
                viewPosition.x = Math.max(textLength - viewLength, 0);
                viewport.setViewPosition(viewPosition);
                //System.out.println("Utilities.createSingleLineEditor(): setting new view position = "+viewPosition);
            }
        } catch (BadLocationException blex) {
            Exceptions.printStackTrace(blex);
        }
    }
}
 

import javax.swing.JViewport; //导入方法依赖的package包/类
private int[] computeVisibleSpan() {
    Component parent = pane.getParent();
    
    if (parent instanceof JLayeredPane) {
        parent = parent.getParent();
    }

    if (parent instanceof JViewport) {
        JViewport vp = (JViewport) parent;

        Point start = vp.getViewPosition();
        Dimension size = vp.getExtentSize();
        Point end = new Point((int) (start.getX() + size.getWidth()), (int) (start.getY() + size.getHeight()));

        int startPosition = pane.viewToModel(start);
        int endPosition = pane.viewToModel(end);

        if (parentWithListener != vp) {
            vp.addChangeListener(WeakListeners.change(this, vp));
            parentWithListener = vp;
        }
        return new int[] {startPosition, endPosition};
    }

    return new int[] {0, pane.getDocument().getLength()};
}
 

import javax.swing.JViewport; //导入方法依赖的package包/类
/** notify the Component to autoscroll */
public void autoscroll(Point cursorLoc) {
    JViewport viewport = getViewport();
    Point viewPos = viewport.getViewPosition();
    int viewHeight = viewport.getExtentSize().height;

    if ((cursorLoc.y - viewPos.y) <= realInsets.top) {
        // scroll up
        viewport.setViewPosition(new Point(viewPos.x, Math.max(viewPos.y - realInsets.top, 0)));
    } else if (((viewPos.y + viewHeight) - cursorLoc.y) <= realInsets.bottom) {
        // scroll down
        viewport.setViewPosition(
            new Point(viewPos.x, Math.min(viewPos.y + realInsets.bottom, this.getHeight() - viewHeight))
        );
    }
}
 

import javax.swing.JViewport; //导入方法依赖的package包/类
@Override
public void actionPerformed(ActionEvent evt) {
    Component component = ZoomMenu.this.jgraph.getParent();
    while (component != null && !(component instanceof JViewport)) {
        component = component.getParent();
    }
    if (component != null) {
        final JViewport viewport = (JViewport) component;
        Rectangle2D graphBounds = ZoomMenu.this.jgraph.getGraphBounds();
        Dimension viewportBounds = viewport.getExtentSize();
        double scale =
            Math.min(viewportBounds.width / graphBounds.getWidth(), viewportBounds.height
                / graphBounds.getHeight());
        ZoomMenu.this.jgraph.setScale(Math.min(scale, 1.0));
        ZoomMenu.this.jgraph.scrollRectToVisible(graphBounds.getBounds());
        setActionsEnabled();
    }
}
 

import javax.swing.JViewport; //导入方法依赖的package包/类
public void validateThird() {
    JViewport viewport = this.pane.getViewport();
    JScrollBar scroller = this.pane.getHorizontalScrollBar();
    if (!scroller.getComponentOrientation().equals(ComponentOrientation.RIGHT_TO_LEFT)) {
        throw new Error("unexpected component orientation");
    }
    int value = scroller.getValue();
    if (value != 0) {
        throw new Error("unexpected scroll value");
    }
    int extent = viewport.getExtentSize().width;
    if (extent != scroller.getVisibleAmount()) {
        throw new Error("unexpected visible amount");
    }
    int size = viewport.getViewSize().width;
    if (size != scroller.getMaximum()) {
        throw new Error("unexpected maximum");
    }
    int pos = size - extent - value;
    if (pos != viewport.getViewPosition().x) {
        throw new Error("unexpected position");
    }
}
 

import javax.swing.JViewport; //导入方法依赖的package包/类
/** Performs autoscroll operation.
*/
public void autoscroll(Point cursorLoc) {
    JViewport viewport = getViewport();

    if (viewport == null) {
        return;
    }

    Point viewPos = viewport.getViewPosition();
    int viewHeight = viewport.getExtentSize().height;
    int viewWidth = viewport.getExtentSize().width;

    // perform scrolling
    if ((cursorLoc.y - viewPos.y) < insets.top) {
        // scroll up
        viewport.setViewPosition(new Point(viewPos.x, Math.max(viewPos.y - scrollUnits.top, 0)));
    } else if (((viewPos.y + viewHeight) - cursorLoc.y) < insets.bottom) {
        // scroll down
        viewport.setViewPosition(
            new Point(viewPos.x, Math.min(viewPos.y + scrollUnits.bottom, comp.getHeight() - viewHeight))
        );
    } else if ((cursorLoc.x - viewPos.x) < insets.left) {
        // scroll left
        viewport.setViewPosition(new Point(Math.max(viewPos.x - scrollUnits.left, 0), viewPos.y));
    } else if (((viewPos.x + viewWidth) - cursorLoc.x) < insets.right) {
        // scroll right
        viewport.setViewPosition(
            new Point(Math.min(viewPos.x + scrollUnits.right, comp.getWidth() - viewWidth), viewPos.y)
        );
    }
}
 

import javax.swing.JViewport; //导入方法依赖的package包/类
private void adjustTreeScrollBar(int treeViewWidth) {
    DebugTreeView tView = getTreeView();
    if (tView == null) {
        scrollBarPanel.setVisible(false);
        return;
    }
    JViewport viewport = tView.getViewport();
    Point point = viewport.getViewPosition();
    if (point.y < 0) {
        viewport.setViewPosition(new Point(point.x, 0));
    }
    Dimension viewSize = viewport.getExtentSize();
    Dimension treeSize = viewport.getViewSize();
    if (treeViewWidth < 0) {
        treeViewWidth = treeSize.width;
    }
    int unitHeight = tView.getUnitHeight();
    if (unitHeight > 0) {
        JScrollBar sbar = mainScrollPane.getVerticalScrollBar();
        if (sbar.getUnitIncrement() != unitHeight) {
            sbar.setUnitIncrement(unitHeight);
        }
    }
    if (treeViewWidth <= viewSize.width) {
        scrollBarPanel.setVisible(false);
    } else {
        treeScrollBar.setMaximum(treeViewWidth);
        treeScrollBar.setVisibleAmount(viewSize.width);
        if (unitHeight > 0) {
            treeScrollBar.setUnitIncrement(unitHeight / 2);
        }
        treeScrollBar.setBlockIncrement(viewSize.width);
        scrollBarPanel.setVisible(true);
    } // else
}