There two main issues that trigger tax obligation - source of income and residency.
As a resident of a specific state - you would pay state income taxes regardless of source of the income.
If the income is from California sources - "California-based source income" - you would pay California taxes on that income regardless of your residency. The question is which income is considered from California sources?
As a non-resident partner of the partnership with California-source income - the income/loss distributed to you would be considered from California sources and will be taxable for you. The same is true for shareholders of an S-corporation and LLC.
For instance - a Delaware general partnership owns a California property which generates income - such income distributed of deemed distributed to the partners living in Nevada would be taxable California-source income.
Intangible property are generally sourced at the owner's residency - if you are a non-resident investor who purchased stock/bonds - considered intangible assets - of a California corporation or through a California broker - dividends would not be taxable.
A California resident is an individual who is in California for other than temporary reasons - who is working, living, retiring or staying in California for a long period - you are presumed a resident if you stay in California for more than nine months. For more information - see FTB Publication 1031, Guidelines for Determining Resident Status - http://www.ftb.ca.gov/forms/07_forms/07_1031.pdf