Question

navigationbar默认的线该如何去掉

Answer 1

读读这篇文档你就明白了
barStyle

The appearance of the navigation bar.

@property(nonatomic, assign) UIBarStyle barStyle

Discussion

See UIBarStyle for possible values. The default value is UIBarStyleDefault.

It is permissible to set the value of this property when the navigation bar is being managed by a navigation controller object.

Availability

Available in iOS 2.0 and later.

Related Sample Code

NavBar

Declared In

UINavigationBar.h

UIBaselineAdjustment

Vertical adjustment options.

typedef enum {
UIBaselineAdjustmentAlignBaselines,
UIBaselineAdjustmentAlignCenters,
UIBaselineAdjustmentNone,
} UIBaselineAdjustment;
Constants

UIBaselineAdjustmentAlignBaselines
Adjust text relative to the position of its baseline.

Available in iOS 2.0 and later.

Declared in UIStringDrawing.h.

UIBaselineAdjustmentAlignCenters
Adjust text based relative to the center of its bounding box.

Available in iOS 2.0 and later.

Declared in UIStringDrawing.h.

UIBaselineAdjustmentNone
Adjust text relative to the top-left corner of the bounding box. This is the default adjustment.

Available in iOS 2.0 and later.

Declared in UIStringDrawing.h.

Discussion

Baseline adjustment options determine how to adjust the position of text in cases where the text must be drawn using a different font size than the one originally specified. For example, with the UIBaselineAdjustmentAlignBaselines option, the position of the baseline remains fixed at its initial location while the text appears to move toward that baseline. Similarly, the UIBaselineAdjustmentNone option makes it appear as if the text is moving upwards towards the top-left corner of the bounding box.