IOS 10开发中经常遇到的问题总结
ios 10开发中经常遇到的问题总结。
1.如何手动取消uidispalaysearchcontroller的取消搜索状态
#pragmamarkuisearchdisplaydelegate
-(void)searchdisplaycontrollerdidbeginsearch:(uisearchdisplaycontroller*)controller
{
for(uiview*viewincontroller.searchbar.subviews)
{
nslog(@"%d__|---%@",__line__,view);
for(uiview*subviewinview.subviews)
{
nslog(@"%d__|!!!%@",__line__,subview);
//获取"取消"按钮
if([subviewiskindofclass:[uibuttonclass]])
{
uibutton*cancelbutton=(uibutton*)subview;
//获取点击"取消"按钮的响应事件(actionsfortarget这个方法返回的是一个数组)
self.cancelsearchselstring=[[cancelbuttonactionsfortarget:controller.searchbarforcontrolevent:uicontroleventtouchupinside]objectatindex:0];
//响应通知,执行方法直接用上面获得的响应事件方法,转换一下(这是个知识点,可以扩展下)
[[nsnotificationcenterdefaultcenter]addobserver:controller.searchbarselector:nsselectorfromstring(self.cancelsearchselstring)name:@"cancelsearch"object:nil];
}
}
}
}
#pragmamarkuisearchbardelegate------点击搜索按钮
-(void)searchbarsearchbuttonclicked:(uisearchbar*)searchbar{
//获取你想搜索的最终完整关键字(一般可以用来做搜索历史展示)
nslog(@"%s__%d__|%@",__function__,__line__,searchbar.text);
//点击按钮时,发布取消搜索状态通知
[[nsnotificationcenterdefaultcenter]postnotificationname:@"cancelsearch"object:nil];
//发布---响应---取消通知
[[nsnotificationcenterdefaultcenter]removeobserver:searchbarname:@"cancelsearch"object:nil];
}
2.如何知道导航栏是pop还是push
-(void)viewwilldisappear:(bool)animated
{
[superviewwilldisappear:animated];
if([selfismovingfromparentviewcontroller])
{
nslog(@"viewcontrollerwopped");
}
else
{
nslog(@"newviewcontrollerwaspushed");
}
}
3.更改导航栏颜色
if(nsfoundationversionnumber>nsfoundationversionnumber_ios_6_1){
//tuffforios7andnewer
[self.navigationcontroller.navigationbarsetbartintcolor:[uicoloryellowcolor]];
}
else{
//dostuffforolderversionsthanios7
[self.navigationcontroller.navigationbarsettintcolor:[uicoloryellowcolor]];
}
4.如何更改导航栏title文字的颜色
[self.navigationcontroller.navigationbarsettitletextattributes:
@{nsforegroundcolorattributename:[uicolorredcolor],
nsfontattributename:[uifontfontwithname:@"mplus-1c-regular"size:21]}];
5.减少多余的tableview空的cell
tableview.tablefooterview= [uiview new];
6.返回cgfloat_min
//footer间距
-(cgfloat)tableview:(uitableview*)tableviewheightforfooterinsection:(nsinteger)section
{
//return1.0f;
returncgfloat_min;
}
7.减少默认tableview的sectionheader和footer的高度，直接设置0是无效的，最小是1.0f
-(cgfloat)tableview:(uitableview*)tableview
heightforheaderinsection:(nsinteger)section{
if(section==0){
return6.0;
}
return1.0;
}
-(cgfloat)tableview:(uitableview*)tableview
heightforfooterinsection:(nsinteger)section{
return5.0;
}
-(uiview*)tableview:(uitableview*)tableview
viewforheaderinsection:(nsinteger)section{
return[[uiviewalloc]initwithframe:cgrectzero];
}
-(uiview*)tableview:(uitableview*)tableview
viewforfooterinsection:(nsinteger)section{
return[[uiviewalloc]initwithframe:cgrectzero];
}
8.设置中号字体
uifont*font=[uifontfontwithname:@"helveticaneue-medium"size:14.0f];
//ios8.2开始
[uifontsystemfontofsize:14weight:uifontweightmedium];