You can do it this way:
button = (Button) findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
String ButtonText = button.getText().toString();
if(ButtonText.equals("Save"){
//code for save
button.setText("Edit");
}
else{
//code for edit
button.setText("Save");
}
}
});