Case 1
Put the desired placeholder text in the label property of the TextField component, and use the labelClassName property of the TextField to customize it. You could also pass InputLabelProps with a className, classes or style attribute.
Case 2
Refrain from using the label property of TextField and put the placeholder text on its placeholder property instead. Leverage InputProps to override the generated HTML input element's class.
Code
The code below covers both aforementioned cases. CodeSandbox snippet.
import React from 'react';
import TextField from 'material-ui/TextField';
import { withStyles } from 'material-ui/styles';
import withRoot from '../components/withRoot';
const styles = {
'input-label': {
textOverflow: 'ellipsis',
whiteSpace: 'nowrap',
overflow: 'hidden',
width: '100%',
color: 'red'
},
'input': {
'&::placeholder': {
textOverflow: 'ellipsis !important',
color: 'blue'
}
}
};
class Index extends React.Component {
render() {
return <div style={ {width: 150, margin: '0 auto'} }>
{/* Uses "label" and "labelClassName". */}
<TextField
fullWidth
label='I am a really really long red TextField label'
labelClassName={ this.props.classes['input-label'] } />
{/* Uses "label" and "InputLabelProps" with inline styles. */}
<TextField
fullWidth
label='I am a really really long green TextField label'
InputLabelProps={{
style: {
textOverflow: 'ellipsis',
whiteSpace: 'nowrap',
overflow: 'hidden',
width: '100%',
color: 'green'
} }} />
{/* Uses "placeholder" and "InputProps" with "classes". */}
<TextField
fullWidth
margin='normal'
placeholder='I am a really really long glue TextField label'
InputProps={{ classes: {input: this.props.classes['input']} }} />
</div>;
}
}
export default withStyles(styles)(Index);
EDIT
The previous solutions are good if you'd like to personalize a specific component instance. To change the placeholder globally, see ninjaPixel's answer.