iOS development graphics draw, draw lines, rectangles, and draw text vertically and centered

Overview

The graphics drawing under iOS in The Spit slot, the code is lengthy, and has to be re-packaged by itself. Collation forms this article.

Draw lines

// Draw line + (void) Todrawlinefromx: (cgfloat) x1 Y: (cgfloat) y1 ToX: (cgfloat) x2 ToY: (cgfloat) y2 context :(cgcontextref) con{    cgcontextmovetopoint (Con, x1, y1);    Cgcontextaddlinetopoint (Con, x2, y2);     1);    Cgcontextstrokepath (con);}

Draw a rectangle

//Draw Rectangle, FillColor fill Color+ (void) Todrawrect: (cgrect) Rectangle Color:fillcolor Context: (cgcontextref) ctx{//create a path and get a handlecgmutablepathref Path=cgpathcreatemutable (); //Add a rectangle to the pathcgpathaddrect (path,null, rectangle); //Get Context//to add a path to the contextCgcontextaddpath (CTX, path); //Set Rectangle fill Color[FillColor Setfill]; //Rectangle Border Color[[Uicolor Whitecolor] setstroke]; //Border WidthCgcontextsetlinewidth (ctx,0); //DrawingCgcontextdrawpath (CTX, Kcgpathfillstroke); Cgpathrelease (path);}

Draw text vertically and centered

///Draw Text, rect1 the specified rectangle, and draw the text horizontally and vertically centered in the rectangle+ (void) Todrawtextwithrect: (cgrect) rect1 str: (nsstring*) str1 Context: (cgcontextref) context{if(str1 = = Nil | | context = =Nil)return; Cgcontextsetlinewidth (Context,1.0); Cgcontextsetrgbfillcolor (Context,0.01, 0.01, 0.01, 1); //paragraph formatNsmutableparagraphstyle *textstyle =[[Nsmutableparagraphstyle Defaultparagraphstyle] mutablecopy]; Textstyle.linebreakmode=nslinebreakbywordwrapping; Textstyle.alignment= Nstextalignmentcenter;//Center Horizontally//FontUifont *font = [Uifont boldsystemfontofsize:22.0]; //building a collection of propertiesNsdictionary *attributes =@{nsfontattributename:font, Nsparagraphstyleattributename:textstyle}; //Get SizeCgsize strsize =[str1 sizewithattributes:attributes]; CGFloat margintop= (rect1.size.height-strsize.height)/2; //Center vertically to calculate for yourselfCGRect r = CGRectMake (rect1.origin.x, RECT1.ORIGIN.Y +margintop,rect1.size.width, strsize.height); [str1 drawinrect:r withattributes:attributes];}

How to use

Suppose you put the above method into a class in Drawutil, we can Drawutil to invoke the method.

Definition: #define DRAWLINE (X1,y1,x2,y2,con) [Drawutil todrawlinefromx:x1 y:y1 tox:x2 toy:y2 Context:con]

Get context

　　Cgcontextref con = uigraphicsgetcurrentcontext();

cgcontextclearrect(con, rect);

Draw lines,

DrawLine(x,y,x+rectwidth, Y,con);

Rectangular

[drawutil todrawrect :cgrectmake (x*unitwidth+< Span class= "S5" >1unitheight+1 ,unitwidth-1unitheight-1) color :[uicolor whitecolor context:con];

Text

[drawutil todrawtextwithrect: rect1 str: @ "You" context: context];

iOS development graphics draw, draw lines, rectangles, and draw text vertically and centered