How to use keydown event in Ext.Message.Box

Question

I want to add keydown event that fired when i press more than 250 character. here is the code,

var c = Ext.MessageBox.show({
    title: "Version Remarks",
    id:'test',
    inputType: "textareafield",
    msg:"Please Enter Version Remarks: (Only 250 Character)",
    width: 375,
    buttons: Ext.MessageBox.OKCANCEL,
    multiline: true,
    label: Ext.MessageBox.label,
    fn: b,
    icon: Ext.MessageBox.INFO,
    modal: true,
    closable: false,
    allowBlank: false,

});

c.textArea.on('change', function (e, text, o) {

    if (text.length > 250) {
        c.msgButtons.ok.setDisabled(true);
        //c.label.setText("This is the label");
        alert("You are not able to enter more than 250 Character.!!")
    } else {
        c.msgButtons.ok.setDisabled(false);
    }
}

when i pressed 251 character the popup was display and also allow me to enter the character but now i want to use onkeydown event which not allow the user to enter any character more than 250 character.

Answer 1

I tried this and it's also worked.

var c = Ext.MessageBox.show({
        title: "Version Remarks",
        id: 'test',
        inputType: "textareafield",
        msg: "Please Enter Version Remarks: (Only 250 Character)",
        width: 375,
        buttons: Ext.MessageBox.OKCANCEL,
        multiline: true,
        label: Ext.MessageBox.label,
        fn: b,
        icon: Ext.MessageBox.INFO,
        modal: true,
        closable: false,
        allowBlank: false,

    });

    c.textField.maxLength = 250;
    c.textArea.el.dom.querySelector('textarea').onkeyup = function () {
        if (this.value.length > 250) {
            this.value = this.value.substr(0, 250);
            alert("Maximum 250 characters are allowed for version remark.");
            return false;
        }
    };