I'm querying the CallLog content provider and need to detect the column types.
In Honeycomb and newer (API Level 11+) you can get a columns preferred data type by calling the method Cursor.getType(int columnIndex)
which returns one of the following types:
- FIELD_TYPE_NULL (0)
- FIELD_TYPE_INTEGER (1)
- FIELD_TYPE_FLOAT (2)
- FIELD_TYPE_STRING (3)
- FIELD_TYPE_BLOB (4)
How can I accomplish this on pre-Honeycomb <11 devices?
I've tried the following:
for ( int i = 0; i < cursor.getColumnCount(); i++ ) {
int columnType = -1;
try {
cursor.getInt( i );
columnType = Cursor.FIELD_TYPE_INTEGER;
} catch ( Exception ignore ) {
try {
cursor.getString( i );
columnType = Cursor.FIELD_TYPE_STRING;
} catch ( Exception ignore1 ) {
try {
cursor.getFloat( i );
columnType = Cursor.FIELD_TYPE_FLOAT;
} catch ( Exception ignore2 ) {
try {
cursor.getBlob( i );
columnType = Cursor.FIELD_TYPE_BLOB;
} catch ( Exception ignore3 ) {
columnType = Cursor.FIELD_TYPE_NULL;
}
}
}
}
}
However, no exception is thrown. The data is always casted in the first type you are checking for, in this case getInt(). That means, I get the correct values if the column type is Integer but a 0 for all other types.
Why am I not looking in the documentation to check what type is stored?
The columns differ depending on the device manufacturer and not all of them are documented, see this question: How to handle manufacturer-dependent differences in ContentProviders?
Any ideas?
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