Custom Formula Functions"
| Line 16: | Line 16: | ||
Basically, to implement a formula is just like implementing a static Java method, but depending on your requirements there are several ways to do it. We will introduce them from easy to complicated one. | Basically, to implement a formula is just like implementing a static Java method, but depending on your requirements there are several ways to do it. We will introduce them from easy to complicated one. | ||
| − | == | + | == Basic - Simple Formula== |
If your formula accepts fixed number of arguments and each argument is a single value (or a reference to a single cell), you can use this way to implement your custom formula. | If your formula accepts fixed number of arguments and each argument is a single value (or a reference to a single cell), you can use this way to implement your custom formula. | ||
| − | |||
Assume that we are going to create a money exchange formula that accepts 2 double arguments and return exchange result. The first one is money, and the second one is exchange rate. | Assume that we are going to create a money exchange formula that accepts 2 double arguments and return exchange result. The first one is money, and the second one is exchange rate. | ||
<source lang='java'> | <source lang='java'> | ||
public class MyCustomFormulas { | public class MyCustomFormulas { | ||
| − | + | ||
public static double exchange(double money, double exchangeRate) { | public static double exchange(double money, double exchangeRate) { | ||
| − | + | return money * exchangeRate; | |
| − | + | } | |
} | } | ||
</source> | </source> | ||
| − | |||
| − | |||
| − | |||
| − | == | + | After declare it in a ZUL page, you can use this formula like <tt>=EXCHANGE(10, 31.3)</tt> or <tt>=EXCHANGE(C3, D3)</tt>. Spreadsheet will evaluate each argument and pass them to <tt>exchange()</tt> method. If you pass a reference to a range of cells in this formula, e.g. <tt>=EXCHANGE(C3:C4, D3)</tt>, only the first cell will be evaluated. |
| + | |||
| + | |||
| + | == Intermediate - Multiple Arguments Numeric Formula == | ||
| − | == | + | == Advanced - Multiple Arguments Formula == |
Revision as of 09:02, 17 July 2013
Overview
Spreadsheet allows developers to implement their own custom formulas and use these formulas like built-in ones. You can just enter your custom formula like =MYFORMULA(A1) and it works like other formulas. To implement such a custom method is easy: just create a static method and declare it in a ZUL page with EL method or tag library.
Steps to add a custom formula:
- Implement a public static method
- Declare in a ZUL page with Spreadsheet component
After completing above steps, you can use the custom formula in Spreadsheet.
Implement a Formula
Basically, to implement a formula is just like implementing a static Java method, but depending on your requirements there are several ways to do it. We will introduce them from easy to complicated one.
Basic - Simple Formula
If your formula accepts fixed number of arguments and each argument is a single value (or a reference to a single cell), you can use this way to implement your custom formula.
Assume that we are going to create a money exchange formula that accepts 2 double arguments and return exchange result. The first one is money, and the second one is exchange rate.
public class MyCustomFormulas {
public static double exchange(double money, double exchangeRate) {
return money * exchangeRate;
}
}
After declare it in a ZUL page, you can use this formula like =EXCHANGE(10, 31.3) or =EXCHANGE(C3, D3). Spreadsheet will evaluate each argument and pass them to exchange() method. If you pass a reference to a range of cells in this formula, e.g. =EXCHANGE(C3:C4, D3), only the first cell will be evaluated.