Recently made a private rental system, there are nine table, the base has basically completed its function, is to what ZJ had nine tables to be statistical when (rent) field statistical summation,
The execution of a function is realized, it is, a few flashes in the DBGrid, then the results, good ugly, poor effect is good;
My query is: ordinal sum each table, will output the result set into DBGrid table, and then get the value from the DBGrid saved to an Int variable,
Finally add those nine variables,
I think excuse me, how to solve the flicker?? Or is my method is wrong, isn't it can query result set implicit access to variable??????

CodePudding user response:

And in the Form of Show events this - & gt; DoubleBuffered=true;

CodePudding user response:

@ songhtao
I have just joined this code, or I can't, the DBGrid queries using SQL statements can get in other places?

CodePudding user response:

My code is such (fragment) :

 
int a,b; 
SqlCmd="SELECT sum (what zj had) FROM room_1;"; 
ADOQuery2 - & gt; SQL - & gt; The Clear ();//must Clear before we Add finally Open, the order cannot change 
ADOQuery2 - & gt; SQL - & gt; Add (sqlCmd); 
ADOQuery2 - & gt; The Open ();//can check 
//ADOQuery2 - & gt; EnableControls (); 
A=DBGrid1 - & gt; The Columns - & gt; The Grid - & gt; Fields [0] - & gt; The Value; 
//a=DBGrid1 - & gt; ` FieldByName (" total_title ") - & gt; AsString; 

//ADOQuery2 - & gt; DisableControls (); 
SqlCmd="SELECT sum (what zj had) FROM room_2;"; 
ADOQuery2 - & gt; SQL - & gt; The Clear (); 
ADOQuery2 - & gt; SQL - & gt; Add (sqlCmd); 
ADOQuery2 - & gt; The Open ();//can check 
//ADOQuery2 - & gt; EnableControls (); 
B=DBGrid1 - & gt; The Columns - & gt; The Grid - & gt; Fields [0] - & gt; The Value; 
Total=a + b; 
ShowMessage (" \ t rent statistics \ n \ n "
"\ t1 floor:" + IntToStr (a) + "yuan t \ \ t \ n +" 
"\ t2 floor:" + IntToStr (b) + "\ n" + 
"\ t total:" + IntToStr (total) + "\ n"); 

My operation is not correct??

CodePudding user response:

 ADOQuery2 - & gt; DisableControls (); 

.//database operations 
. 
. 

ADOQuery2 - & gt; EnableControls (); 

.//interface 
. 

CodePudding user response:

Fyi:
http://blog.163.com/tab_98/blog/static/119240972015925111011673/

CodePudding user response:

I define a variable
Int the save;
And then through the SQL statements to integrate the results get DBGird table, and then save to the value read from a DBGird table in front of the save variable,
Read a table like this also like no flicker, but read several tables have this kind of circumstance happening, I think whether I operation method with problem??

CodePudding user response:

In your database, create a temporary table, every time the result of calculation, stored in the temporary table (temporary table will empty it before each use), then use DBGRID one-time read out the contents of the temporary table is ok,,,,

CodePudding user response:

This data summation problem, in principle, should not be done through interface, should all data operations, summation, are finished in the database, don't mess up and interface, together,

CodePudding user response:

In the form of the constructor:
This - & gt; DoubleBuffered=true;
DBGrid1 - & gt; DoubleBuffered=true;

Reference:
http://blog.163.com/tab_98/blog/static/1192409720167475319874/