Disable small character EditText InputType

You can do it through code as follow:

Applying UpperCase as the only filter to an EditText

Here we are setting the UpperCase filter as the only filter of the EditText. Notice that doing it this way you are removing all the previously added filters(maxLength, maxLines,etc).

editText.setFilters(new InputFilter[] {new InputFilter.AllCaps()});

Adding UpperCase to the existing filters of an EditText

To keep the already applied filters of the EditText (let's say maxLines, maxLength, etc) you need to retrieve the applied filters, add the UpperCase filter to those filters, and set them back to the EditText. Here is an example how:

InputFilter[] editFilters = editText.getFilters();
InputFilter[] newFilters = new InputFilter[editFilters.length + 1];
System.arraycopy(editFilters, 0, newFilters, 0, editFilters.length);
newFilters[editFilters.length] = new InputFilter.AllCaps();  
editText.setFilters(newFilters);

It works for me, Try this

edittext.setInputType(InputType.TYPE_CLASS_TEXT);
edittext.setFilters(new InputFilter[]{new InputFilter.AllCaps()});

You can control to respond directly to keyboard input for user actions. Check this link

Yes you can set programmatically. Android has built-in IntentFilter for this.

you can achieve this by using following code-:

editText.setFilters(new InputFilter[] {new InputFilter.AllCaps()});

But, there is an issue setFilters will reset all other attributes which were set via XML (like maxLines, inputType and other)

So, you need to set Filter like this,

InputFilter[] editFilters = <EditText>.getFilters();
InputFilter[] newFilters = new InputFilter[editFilters.length + 1];
System.arraycopy(editFilters, 0, newFilters, 0, editFilters.length);
newFilters[editFilters.length] = new InputFilter.AllCaps();  
//you can use another filter like for maxLength you can use
// newFilters[editFilters.length] = new InputFilter.LengthFilter(10);
<EditText>.setFilters(newFilters);

See here for information

This will work for you.

YES you can do something like that

you can check for every letter typed by the user if it small letter convert it to its upper one

For Example:-

if the user typed e replace it with E