android onkeyup监听,java – Android开发：如何使用onKeyUp？

正确的方法是使用TextWatcher类.

EditText tv_filter = (EditText) findViewById(R.id.filter);

TextWatcher fieldValidatorTextWatcher = new TextWatcher() {

@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 (filterLongEnough()) {

populateList();

}

}

private boolean filterLongEnough() {

return tv_filter.getText().toString().trim().length() > 2;

}

};

tv_filter.addTextChangedListener(fieldValidatorTextWatcher);