How to set the default storage location of SMS in android source code

Samsung W899 Android phone sets the default storage steps: 1. After opening the phone interface, drag the red box down; 2. Then click the screw button in the upper right corner in the interface that appears; 3. Click Save in the next interface; 4. The next interface is like this; 5. Click on the words default storage location; 6. Next, display the default storage location option; 7. You can choose the default storage location between the phone memory and the sd card; 8. If one of them is selected, click OK Next, and then restart the phone. The default location will take effect according to the settings just now.