Show keyboard programmatically using React native
consider have a reference of your textInput :
<TextInput ref={(ref)=>{this.myTextInput = ref}} />
And when you have to focus it again use : this.myTextInput.focus()
edit React16
For react16 use React.createRef
to create a reference.
Your ScrollView needs to include the keyboardShouldPersistTaps prop:
<ScrollView keyboardShouldPersistTaps></ScrollView>