package com.myapplication;
import android.os.Bundle;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.text.Editable;
import android.text.InputType;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.text.method.PasswordTransformationMethod;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Button;
import android.widget.Toast;
public class LoginActivity extends AppCompatActivity {
EditText login_uname, login_pwd;
TextView invalid_error;
Button login_btn;
private boolean canExit;
TextView pword_showhide;
// string login_un,login_pw;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.login_screen);
login_uname = (EditText) findViewById(R.id.login_username);
login_pwd = (EditText) findViewById(R.id.login_password);
invalid_error = (TextView) findViewById(R.id.InvalidError);
login_btn = (Button) findViewById(R.id.login_btn);
// loginbutton.setEnabled(false);
invalid_error.setVisibility(View.GONE);
pword_showhide = (TextView) findViewById(R.id.pwd_showhide);
// pword_showhide.setText("show");
pword_showhide.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (login_pwd.getInputType() == InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD) {
login_pwd.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
pword_showhide.setText("show");
} else {
login_pwd.setInputType(InputType.TYPE_TEXT_VARIATION_VISIBLE_PASSWORD);
pword_showhide.setText("hide");
}
login_pwd.setSelection(login_pwd.getText().length());
}
});
checkValidation();
login_uname.addTextChangedListener(mWatcher);
login_pwd.addTextChangedListener(mWatcher);
}
private void checkValidation() {
// TODO Auto-generated method stub
if ((TextUtils.isEmpty(login_uname.getText())) || (TextUtils.isEmpty(login_pwd.getText())))
login_btn.setEnabled(false);
else {
login_btn.setEnabled(true);
}
}
public void login(View view) {
if (login_uname.getText().toString().equals("a") && login_pwd.getText().toString().equals("a")) {
invalid_error.setVisibility(View.GONE);
Toast.makeText(getApplicationContext(), "Login Success", Toast.LENGTH_LONG).show();
login_uname.setCompoundDrawablesWithIntrinsicBounds(R.drawable.icon_username, 0, 0, 0);
login_pwd.setCompoundDrawablesWithIntrinsicBounds(R.drawable.icon_password, 0, 0, 0);
//correcct password
} else {
//wrong password
invalid_error.setVisibility(View.VISIBLE);
Toast.makeText(getApplicationContext(), "Login fail", Toast.LENGTH_LONG).show();
login_uname.setCompoundDrawablesWithIntrinsicBounds(R.drawable.error_username, 0, 0, 0);
login_pwd.setCompoundDrawablesWithIntrinsicBounds(R.drawable.error_password,0, 0, 0);
}
}
TextWatcher mWatcher = new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
checkValidation();
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
};
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onBackPressed() {
if (canExit)
super.onBackPressed();
else {
canExit = true;
Toast.makeText(getApplicationContext(), "Press again to Exit", Toast.LENGTH_SHORT).show();
}
mHandler.sendEmptyMessageDelayed(1, 2000/*time interval to next press in milli second*/);// if not pressed within 2seconds then will be setted(canExit) as false
}
private Handler mHandler = new Handler() {
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case 1:
canExit = false;
break;
default:
break;
}
}
};
}
login_screen.xml
----------------
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".LoginActivity">
<TextView
android:layout_width="match_parent"
android:layout_height="40dp"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Invalid Login Details"
android:id="@+id/InvalidError"
android:gravity="center"
android:background="#ff3a0f"
android:textColor="#FFF"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="fill_parent"
android:layout_margin="50dp"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:id="@+id/login_lyt">
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/login_username"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:hint="User Name"
android:drawableLeft="@drawable/icon_username"
android:layout_marginTop="141dp" />
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:inputType="textPassword"
android:hint="******"
android:drawableLeft="@drawable/icon_password"
android:ems="10"
android:id="@+id/login_password"
android:layout_centerVertical="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<TextView
android:id="@+id/pwd_showhide"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/login_password"
android:layout_alignBottom="@+id/login_password"
android:layout_alignParentRight="true"
android:text="show" />
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Login"
android:onClick="login"
android:background="#f0a422"
android:id="@+id/login_btn"
android:layout_below="@+id/login_password"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="31dp"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
</RelativeLayout>
</RelativeLayout>