How does Extjs4.0ComboBox implement level-3 linkage _ extjs

Many netizens are curious about how Extjs4.0ComboBox achieves three-level linkage. The clear point is how to use load to obtain data in extjs4.0, below is a small series to share with you the specific steps many netizens are asking how to implement Extjs4.0 ComboBox. Fortunately, we used 3 before. x has achieved a three-level linkage, and now Extjs4.0 is used to achieve the same linkage effect. Note that: 3. model: 'local' in x is expressed in queryMode: 'local' in Extjs4.0, and in 3. reload is used when loading data in x, but Load is used in extjs4.0 to obtain data. For example:

Code Section

First look at the HTML code:

 MHZG. NET-three-level urban linkage instance