How to Change Font Family for textInput Placeholder in React Native

Try this :

<TextInput
    secureTextEntry={(this.state.email.length <= 0 && this.state.emailStatus != 'onFocus') ? true : false}
    style={styles.textboxfieldd}
    placeholderStyle={styles.textboxfieldd}
    onFocus={this.changeStatus.bind(this, 'emailStatus', 'onFocus', '')}
    onChangeText={(email) => this.setState({ email })}
    value={this.state.email}
    placeholder={this.state.emailStatusPH}
    placeholderTextColor="#D8D8D8" />

Exactly this line => secureTextEntry={(this.state.email.length<=0 && this.state.emailStatus!='onFocus') ?true:false} solves the problem .

Because if we give secureTextEntry={true} means fontfamily is set to placeholder text but field changed as password , so for that only we wrote like this . secureTextEntry={(this.state.email.length<=0 && this.state.emailStatus!='onFocus') ?true:false}

If that field length is 0 and not focused means it will set true secureTextEntry={true} so the placeholder text is set to mentioned fontfamily

The way I solved this was to conditionally style the fontFamily (or style) on the presence or absence of the value i.e.

<TextInput
  style={{ fontFamily: value ? 'OpenSans-Regular' : 'OpenSans-Italic' }}
  value={value}
  onChangeText={onChange}
/>

This way the font family is italic for the placeholder (when value === '') and regular when text is shown.

Above is not tested as I was using styled components but concept should be the same. Also this only works if TextInput is rendered as a controlled component so you have access to value.