I'm new to iOS programming.
Recently, I'm trying to make a UIPickerView as an inputView in UITextfield.
The data in UIPickerView is about all the iOS built-in fonts. So I want to make two components in UIPickerView: the first is familyType, and the second is all the fonts in that familyType.
I simulate the code from this answer, but I meet some problem I can't solve. Any help is welcome!
My question is here:
Why rowOneSelected in this function always get 0 first, even I use selectedRowInComponent in advance?
// The number of rows of data
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
if(component == 0)
{
return _fontTypeArray.count;
}
else
{
NSInteger rowOneSelected = [_pickerFont selectedRowInComponent:0];
FontType *temp = _fontTypeArray[rowOneSelected];
NSLog(@"%ld", (long)rowOneSelected); // I use this to debug, and there is a main question: why every time it logs 0 first?
return temp.font.count;
}
}
All my relative code is here:
In ViewController.h:
#import <UIKit/UIKit.h>
#import "MenuLayerTwoPlusThree.h"
@interface ViewController : UIViewController
@property MenuLayerTwoPlusThree *layerTwoPlusThree;
- (void)createLayerTwoPlusThree;
@end
In ViewController.m:
- (void)viewDidLoad {
[super viewDidLoad];
[self createLayerTwoPlusThree];
}
- (void)createLayerTwoPlusThree
{
_layerTwoPlusThree = [MenuLayerTwoPlusThree alloc];
[_layerTwoPlusThree createFontArray];
[_layerTwoPlusThree createSelectPanel];
}
In FontType.h:
#ifndef FontType_h
#define FontType_h
#import <Foundation/Foundation.h>
@interface FontType : NSObject
@property NSString *familyName;
@property NSMutableArray *font;
@end
#endif /* FontType_h */
In FontType.m:
#import <Foundation/Foundation.h>
#import "FontType.h"
@implementation FontType
@synthesize familyName;
@synthesize font;
@end
In MenuLayerTwoPlusThree.h:
#ifndef MenuLayerTwoPlusThree_h
#define MenuLayerTwoPlusThree_h
#import <UIKit/UIKit.h>
#import "FontType.h"
@interface MenuLayerTwoPlusThree : NSObject<UITextFieldDelegate, UIPickerViewDataSource, UIPickerViewDelegate>
@property UITextField *textFieldFont;
@property NSMutableArray *fontTypeArray;
@property UIPickerView *pickerFont;
@property UIBarButtonItem *doneButton;
@property UIBarButtonItem *spaceButton;
@property UIBarButtonItem *cancelButton;
@property UIToolbar *toolBar;
@property NSArray *toolBarItems;
@property NSInteger familyType;
@property NSInteger fontType;
@property NSString *fontName;
- (void)createFontArray;
- (IBAction)pickerViewButtonClicked:(id)sender;
@end
In MenuLayerTwoPlusThree.m
- (void)createFontArray
{
_fontTypeArray = [[NSMutableArray alloc]initWithCapacity:80];
int number = 0;
for(NSString* family in [UIFont familyNames])
{
//NSLog(@"%@", family);
//number++;
FontType *temp = [[FontType alloc]init];
temp.familyName = family;
temp.font = [[NSMutableArray alloc]init];
int flag = 0;
for(NSString* name in [UIFont fontNamesForFamilyName:family])
{
//NSLog(@" %@", name);
//number++;
flag++;
[temp.font addObject:name];
}
// add Heiti SC, Heiti TC, Telugu Sangam MN, and Bangla Sangam MN to font array
if(flag == 0)
{
[temp.font addObject:family];
}
[_fontTypeArray addObject:temp];
}
// print all fonts test
for(FontType *x in _fontTypeArray)
{
number++;
NSLog(@"%@", x.familyName);
for(NSString *y in x.font)
{
//number++;
NSLog(@"\t%@", y);
}
}
NSLog(@"//////////////////////////////");
NSLog(@"%d", number);
}
- (void)createSelectPanel
{
[self createSelectPanelForPancel1];
[self createSelectPanelForPancel2];
[self createSelectPanelForFont];
[self createSelectPanelForShape];
[self createSelectPanelForEraser];
}
- (void)createSelectPanelForFont
{
_textFieldFont = [[UITextField alloc]initWithFrame:CGRectMake(19, 148, 150, 12)];
[_textFieldFont setBackground:[UIImage imageNamed:@"font-type-bar.png"]];
_textFieldFont.rightViewMode = UITextFieldViewModeAlways;
_textFieldFont.delegate = self;
[_textFieldFont setPlaceholder:@"Heiti TC"];
_textFieldFont.font = [_textFieldFont.font fontWithSize:10 * _aspectRatio];
// resize right view image
UIImageView *rightViewImage = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 12 * _aspectRatio, 12 * _aspectRatio)];
[rightViewImage setImage:[UIImage imageNamed:@"font-type-bar-roll.png"]];
_textFieldFont.rightView = rightViewImage;
_pickerFont = [[UIPickerView alloc]init];
_pickerFont.dataSource = self;
_pickerFont.delegate = self;
_pickerFont.showsSelectionIndicator = YES;
_doneButton = [[UIBarButtonItem alloc]initWithTitle:@"Done" style:UIBarButtonItemStyleDone target:self action:@selector(pickerViewButtonClicked:)];
_spaceButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
_cancelButton = [[UIBarButtonItem alloc]initWithTitle:@"Cancel" style:UIBarButtonItemStylePlain target:self action:@selector(pickerViewButtonClicked:)];
_toolBar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, 45)];
[_toolBar setBarStyle:UIBarStyleDefault];
_toolBarItems = [NSArray arrayWithObjects:_cancelButton, _spaceButton, _doneButton, nil];
[_toolBar setItems:_toolBarItems];
_textFieldFont.inputView = _pickerFont;
_textFieldFont.inputAccessoryView = _toolBar;
if (@available(iOS 9.0, *)) {
_textFieldFont.inputAssistantItem.leadingBarButtonGroups = @[];
} else {
// Fallback on earlier versions
}
if (@available(iOS 9.0, *)) {
_textFieldFont.inputAssistantItem.trailingBarButtonGroups = @[];
} else {
// Fallback on earlier versions
}
// I want to add these codes to select row in advanced to make sure first time NSLog will print 9, but it doesn't work.
// [_pickerFont reloadAllComponents];
// _familyType = 9;
// _fontType = 0;
// _fontName = @"Heiti TC";
// [_pickerFont selectRow:_familyType inComponent:0 animated:YES];
[_selectPanelFontView addSubview:_textFieldFont];
}
And this is the delegate, which I am written in the MenuLayerTwoPlusThree.m:
// The number of columns of data
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
return 2;
}
// The number of rows of data
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
if(component == 0)
{
return _fontTypeArray.count;
}
else
{
NSInteger rowOneSelected = [_pickerFont selectedRowInComponent:0];
FontType *temp = _fontTypeArray[rowOneSelected];
NSLog(@"%ld", (long)rowOneSelected); // I use this to debug, and there is a main question: why every time it logs 0 first?
return temp.font.count;
}
}
// The data to return for the row and component (column) that's being passed in
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
if(component == 0)
{
FontType *temp = _fontTypeArray[row];
return temp.familyName;
}
else
{
NSInteger rowOneSelected = [_pickerFont selectedRowInComponent:0];
FontType *temp = _fontTypeArray[rowOneSelected];
return [temp.font objectAtIndex:row];
}
}
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
if(component == 0)
{
[_pickerFont reloadComponent:1];
}
// This block is moved to pickerViewButtonClicked (sender == _doneButton)
// else
// {
// NSInteger rowOneSelected = [_pickerFont selectedRowInComponent:0];
// FontType *temp = _fontTypeArray[rowOneSelected];
// [_textFieldFont setText:temp.font[row]];
// }
}
- (IBAction)pickerViewButtonClicked:(id)sender
{
if(sender == _doneButton)
{
// Save value when I clicked the done button.
_familyType = [_pickerFont selectedRowInComponent:0];
_fontType = [_pickerFont selectedRowInComponent:1];
// NSLog(@"family: %ld", _familyType);
// NSLog(@"font: %ld", _fontType);
FontType *temp = _fontTypeArray[_familyType];
_fontName = temp.font[_fontType];
[_textFieldFont setText:_fontName];
// NSLog(@"font name: %@", _fontName);
[_textFieldFont endEditing:YES];
}
else if(sender == _cancelButton)
{
[_textFieldFont endEditing:YES];
// I want to turn back to the last selected value when I clicked the cancel button.
[_pickerFont reloadAllComponents];
[_pickerFont selectRow:_familyType inComponent:0 animated:NO];
[_pickerFont selectRow:_fontType inComponent:1 animated:NO];
}
}
It really seems that when the UIPickerView appears as an inputView after you have selected row 9 in component 0, the selectedRowInComponent: 0 returns 0 in numberOfRowsInComponent: 1, but then returns 9 in titleForRow: row forComponent: 1.
I don't think you are doing anything wrong, so it looks like a bug in UIKit.
As a workaround, I suggest you don't ask the picker view for the selected row, but track the selected row yourself (initialize your own variable in your view controller and update it in didSelectRow: row inComponent: 0)