Question

我正在尝试使用Auto Layout to set up scrolling in NSScrollView滚动基于视图的NSTableView。我有几个问题。

最明显的是：如果所有行都可见，则表仍然可以向下滚动一行。例如，在本文结尾处拍摄这些节目之前和之后：

Before After

我猜NSTableHeaderView与NSTableView重叠，但我尝试添加约束，将NSTableView的NSClipView的顶部设置到标题视图的底部及其超级视图（另一个NSClipView，根据实验）。这并没有改变任何事情;似乎只是忽略了约束。

尽可能小地调整窗口大小似乎也会将第一行推出视图，再次生长窗口时会生成第二个图像。

水平滚动也不起作用或非常麻烦，但我想知道这是否是由于列自动调整。

这是在OS X 10.11上，但必须能够工作到10.8。 这不是iOS。

谢谢！

// 22 june 2016
#import <Cocoa/Cocoa.h>

NSLayoutConstraint *mkConstraint(id view1, NSLayoutAttribute attr1, NSLayoutRelation relation, id view2, NSLayoutAttribute attr2, CGFloat multiplier, CGFloat c)
{
    return [NSLayoutConstraint constraintWithItem:view1
        attribute:attr1
        relatedBy:relation
        toItem:view2
        attribute:attr2
        multiplier:multiplier
        constant:c];
}

@interface tableModel : NSObject<NSTableViewDataSource, NSTableViewDelegate>
@end

@implementation tableModel

- (NSInteger)numberOfRowsInTableView:(NSTableView *)tv
{
    return 15;
}

 - (NSView *)tableView:(NSTableView *)table viewForTableColumn:(NSTableColumn *)c row:(NSInteger)row
{
    NSTableCellView *tv;
    NSTextField *tf;

    tv = [[NSTableCellView alloc] initWithFrame:NSZeroRect];

    tf = [[NSTextField alloc] initWithFrame:NSZeroRect];
    [tf setStringValue:[NSString stringWithFormat:@"Row %d", ((int) (row + 1))]];
    [tf setEditable:NO];
    [tf setSelectable:NO];
    [tf setDrawsBackground:NO];
    [tf setFont:[NSFont systemFontOfSize:[NSFont systemFontSizeForControlSize:NSRegularControlSize]]];
    [tf setBordered:NO];
    [tf setBezelStyle:NSTextFieldSquareBezel];
    [tf setBezeled:NO];
    [[tf cell] setLineBreakMode:NSLineBreakByClipping];
    [[tf cell] setScrollable:YES];

    [tf setTranslatesAutoresizingMaskIntoConstraints:NO];
    [tv addSubview:tf];
    [tv addConstraint:mkConstraint(tv, NSLayoutAttributeLeading,
        NSLayoutRelationEqual,
        tf, NSLayoutAttributeLeading,
        1, -2)];
    [tv addConstraint:mkConstraint(tv, NSLayoutAttributeTrailing,
        NSLayoutRelationEqual,
        tf, NSLayoutAttributeTrailing,
        1, 3)];
    [tv addConstraint:mkConstraint(tv, NSLayoutAttributeCenterY,
        NSLayoutRelationEqual,
        tf, NSLayoutAttributeCenterY,
        1, 0)];

    [tv setTranslatesAutoresizingMaskIntoConstraints:NO];
    return tv;
}

@end

NSTableColumn *mkColumn(NSString *title)
{
    NSTableColumn *c;

    c = [[NSTableColumn alloc] initWithIdentifier:@""];
    // via Interface Builder
    [c setResizingMask:(NSTableColumnAutoresizingMask | NSTableColumnUserResizingMask)];
    [c setTitle:title];
    [[c headerCell] setFont:[NSFont systemFontOfSize:[NSFont systemFontSizeForControlSize:NSSmallControlSize]]];
    return c;
}

NSTableView *mkTableView(void)
{
    NSTableView *tv;
    tableModel *model;

    tv = [[NSTableView alloc] initWithFrame:NSZeroRect];

    model = [tableModel new];
    [tv setDataSource:model];
    [tv setDelegate:model];
    [tv reloadData];

    [tv setAllowsColumnReordering:NO];
    [tv setAllowsColumnResizing:YES];
    [tv setAllowsMultipleSelection:NO];
    [tv setAllowsEmptySelection:YES];
    [tv setAllowsColumnSelection:NO];
    [tv setUsesAlternatingRowBackgroundColors:YES];
    [tv setSelectionHighlightStyle:NSTableViewSelectionHighlightStyleRegular];
    [tv setGridStyleMask:NSTableViewGridNone];
    [tv setAllowsTypeSelect:YES];

    // needed to allow the table to grow vertically beyond showing all rows
    [tv setContentHuggingPriority:NSLayoutPriorityDefaultLow forOrientation:NSLayoutConstraintOrientationVertical];

    return tv;
}

NSScrollView *mkScrollView(NSView *dv)
{
    NSScrollView *sv;
    NSView *cv;

    sv = [[NSScrollView alloc] initWithFrame:NSZeroRect];
    [sv setBackgroundColor:[NSColor colorWithCalibratedWhite:1.0 alpha:1.0]];
    [sv setDrawsBackground:YES];
    [sv setBorderType:NSBezelBorder];
    [sv setAutohidesScrollers:YES];
    [sv setHasHorizontalRuler:NO];
    [sv setHasVerticalRuler:NO];
    [sv setRulersVisible:NO];
    [sv setScrollerKnobStyle:NSScrollerKnobStyleDefault];
    [sv setScrollsDynamically:YES];
    [sv setFindBarPosition:NSScrollViewFindBarPositionAboveContent];
    [sv setUsesPredominantAxisScrolling:NO];
    [sv setHorizontalScrollElasticity:NSScrollElasticityAutomatic];
    [sv setVerticalScrollElasticity:NSScrollElasticityAutomatic];
    [sv setAllowsMagnification:NO];

    [dv setTranslatesAutoresizingMaskIntoConstraints:NO];
    [sv setDocumentView:dv];

    cv = [sv contentView];
    [sv addConstraint:mkConstraint(dv, NSLayoutAttributeLeading,
        NSLayoutRelationEqual,
        cv, NSLayoutAttributeLeading,
        1, 0)];
    [sv addConstraint:mkConstraint(dv, NSLayoutAttributeTop,
        NSLayoutRelationEqual,
        cv, NSLayoutAttributeTop,
        1, 0)];
    [sv addConstraint:mkConstraint(dv, NSLayoutAttributeTrailing,
        NSLayoutRelationGreaterThanOrEqual,
        cv, NSLayoutAttributeTrailing,
        1, 0)];
    [sv addConstraint:mkConstraint(dv, NSLayoutAttributeBottom,
        NSLayoutRelationGreaterThanOrEqual,
        cv, NSLayoutAttributeBottom,
        1, 0)];

    return sv;
}

@interface appDelegate : NSObject<NSApplicationDelegate>
@end

@implementation appDelegate

- (void)applicationDidFinishLaunching:(NSNotification *)note
{
    NSWindow *w;
    NSView *contentView;
    NSTableView *tv;
    NSScrollView *sv;

    w = [[NSWindow alloc] initWithContentRect:NSMakeRect(0, 0, 320, 240)
        styleMask:(NSTitledWindowMask | NSClosableWindowMask | NSMiniaturizableWindowMask | NSResizableWindowMask)
        backing:NSBackingStoreBuffered
        defer:YES];
    contentView = [w contentView];

    tv = mkTableView();
    [tv addTableColumn:mkColumn(@"Column")];
    sv = mkScrollView(tv);
    [sv setTranslatesAutoresizingMaskIntoConstraints:NO];
    [contentView addSubview:sv];

    [contentView addConstraint:mkConstraint(contentView, NSLayoutAttributeLeading,
        NSLayoutRelationEqual,
        sv, NSLayoutAttributeLeading,
        1, -20)];
    [contentView addConstraint:mkConstraint(contentView, NSLayoutAttributeTop,
        NSLayoutRelationEqual,
        sv, NSLayoutAttributeTop,
        1, -20)];
    [contentView addConstraint:mkConstraint(contentView, NSLayoutAttributeTrailing,
        NSLayoutRelationEqual,
        sv, NSLayoutAttributeTrailing,
        1, 20)];
    [contentView addConstraint:mkConstraint(contentView, NSLayoutAttributeBottom,
        NSLayoutRelationEqual,
        sv, NSLayoutAttributeBottom,
        1, 20)];

    [w makeKeyAndOrderFront:nil];
}

- (BOOL)applicationShouldTerminateAfterLastWindowClosed:(NSApplication *)app
{
    return YES;
}

@end

int main(void)
{
    NSApplication *app;

    app = [NSApplication sharedApplication];
    [app setActivationPolicy:NSApplicationActivationPolicyRegular];
    [app setDelegate:[appDelegate new]];
    [app run];
    return 0;
}

如何使用自动布局正确设置滚动NSTableView？我所尝试过的有一些奇怪的故障

0 个答案: