Delphi treeview control how data vertical center like binary tree top neutron in the first node in turn below
As shown in figure:


Or any third party controls can

CodePudding user response:

Or redraw can realize also ok, is there any and some thoughts!

CodePudding user response:

No one know?

CodePudding user response:

His painting, is a few round, arrow

CodePudding user response:

Agree with upstairs, yourself. The idea is as follows:

 
//1, to determine the root node location (rectangle), defined as ParentRect 
//the width of the rectangle 
W:=ParentRect. Right - Parent. Left; 
//height 
H:=ParentRect. Bottom - Parent. Top; 
//for ease of calculation and understanding, declare a variable tmpW, said half the width of the 
TmpW: W div=2; 

//2, calculate child node position, defined as ChildRect, if child node number is n, the location of the node number as the index, is: 
//(1) the calculation of rectangular Top, Bottom 
ChildRect. Top:=ParentRect. Bottom; 
ChildRect. Bottom:=ChildRect. Top + H; 

//(2) to calculate the most all child nodes on the left side of the position L 
L:=ParentRect. Left - ((n - 1) * tmpW); 
//(3) calculate all child nodes Left and Right 
For the Index: do the begin=0 to n - 1 
ChildRect [index]. Left:=L + W * index; 
ChildRect [index]. Right:=ChildRect [index] Left + W; 
The end; 
//3, recursive calls to step 2, can calculate the rectangular area of all the node 
//4, recalculate all nodes actually draw area, leave space position, such as: 
ChildDrawRect:=ChildRect; 
With ChildDrawRect do begin 
Top: Top +=(H div 6); 
Bottom:=Bottom - H div (6); 
Left:=Left + div 6 (W); 
Right:=Right - W div (6); 
The end; 
//5, draw the child nodes and the parent node connection link (abbreviated) 

CodePudding user response: