How to use EditText onTextChanged event when I press the number?

问题

I have an EditText with "text = 0.00". When I press the number 3, it should be like 0.03 and the second time when I press the number 5, the text should be 0.35. And 35.0, 35.09 like this. The EditText initially has the value of 0.00.

These are all done with the same EditText.

How do I achieve this? I have tried using addTextChangedListener() with TextWatcher().

回答1:

You have selected correct approach. You have to extend the class with TextWatcher and override afterTextChanged(),beforeTextChanged(), onTextChanged().

You have to write your desired logic in afterTextChanged() method to achieve functionality needed by you.

回答2:

You can also try this:

EditText searchTo = (EditText)findViewById(R.id.medittext);
searchTo.addTextChangedListener(new TextWatcher() {
    @Override
    public void afterTextChanged(Editable s) {
        // TODO Auto-generated method stub
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        // TODO Auto-generated method stub
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
        doSomething();
    } 
});

回答3:

Here, I wrote something similar to what u need:

    inputBoxNumberEt.setText(".     ");
    inputBoxNumberEt.setSelection(inputBoxNumberEt.getText().length());
    inputBoxNumberEt.addTextChangedListener(new TextWatcher() {

        boolean ignoreChange = false;

        @Override
        public void afterTextChanged(Editable s) {
        }

        @Override
        public void beforeTextChanged(CharSequence s, int start,
                                      int count, int after) {
        }

        @Override
        public void onTextChanged(CharSequence s, int start,
                                  int before, int count) {
            if (!ignoreChange) {
                String string = s.toString();
                string = string.replace(".", "");
                string = string.replace(" ", "");
                if (string.length() == 0)
                    string = ".     ";
                else if (string.length() == 1)
                    string = ".  " + string;
                else if (string.length() == 2)
                    string = "." + string;
                else if (string.length() > 2)
                    string = string.substring(0, string.length() - 2) + "." + string.substring(string.length() - 2, string.length());
                ignoreChange = true;
                inputBoxNumberEt.setText(string);
                inputBoxNumberEt.setSelection(inputBoxNumberEt.getText().length());
                ignoreChange = false;
            }
        }
    });

回答4:

put the logic in

afterTextChanged(Editable s) {
    string str = s.toString()
    // use the string str
}

documentation on TextWatcher

来源：https://stackoverflow.com/questions/7432083/how-to-use-edittext-ontextchanged-event-when-i-press-the-number