Added tutorial examples for creating a simple login view #10076

Change-Id: I4cce618a6937cd1c0f3fc57e742666fb4749fa5a

3 files changed, 243 insertions, 0 deletions

diff --git a/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginMainView.java b/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginMainView.java
new file mode 100644
index 0000000000..cb59aa1608
--- /dev/null
+++ b/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginMainView.java
@@ -0,0 +1,42 @@
+package com.vaadin.tests.minitutorials.v70;
+
+import com.vaadin.navigator.View;
+import com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Button.ClickEvent;
+import com.vaadin.ui.CssLayout;
+import com.vaadin.ui.CustomComponent;
+import com.vaadin.ui.Label;
+
+public class SimpleLoginMainView extends CustomComponent implements View {
+
+    public static final String NAME = "";
+
+    Label text = new Label();
+
+    Button logout = new Button("Logout", new Button.ClickListener() {
+
+        @Override
+        public void buttonClick(ClickEvent event) {
+
+            // "Logout" the user
+            getSession().setAttribute("user", null);
+
+            // Refresh this view, should redirect to login view
+            getUI().getNavigator().navigateTo(NAME);
+        }
+    });
+
+    public SimpleLoginMainView() {
+        setCompositionRoot(new CssLayout(text, logout));
+    }
+
+    @Override
+    public void enter(ViewChangeEvent event) {
+        // Get the user name from the session
+        String username = String.valueOf(getSession().getAttribute("user"));
+
+        // And show the username
+        text.setValue("Hello " + username);
+    }
+}
diff --git a/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginUI.java b/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginUI.java
new file mode 100644
index 0000000000..2fbbff10a8
--- /dev/null
+++ b/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginUI.java
@@ -0,0 +1,64 @@
+package com.vaadin.tests.minitutorials.v70;
+
+import com.vaadin.navigator.Navigator;
+import com.vaadin.navigator.ViewChangeListener;
+import com.vaadin.server.VaadinRequest;
+import com.vaadin.ui.UI;
+
+public class SimpleLoginUI extends UI {
+
+    @Override
+    protected void init(VaadinRequest request) {
+
+        /*
+         * Create a new instance of the navigator. The navigator will attach
+         * itself automatically to this view.
+         */
+        new Navigator(this, this);
+
+        /*
+         * The initial log view where the user can login to the application
+         */
+        getNavigator().addView(SimpleLoginView.NAME, SimpleLoginView.class);
+
+        /*
+         * Add the main view of the application
+         */
+        getNavigator().addView(SimpleLoginMainView.NAME,
+                SimpleLoginMainView.class);
+                       
+        /*
+         * We use a view change handler to ensure the user is always redirected
+         * to the login view if the user is not logged in.
+         */
+        getNavigator().addViewChangeListener(new ViewChangeListener() {
+            
+            @Override
+            public boolean beforeViewChange(ViewChangeEvent event) {
+                
+                // Check if a user has logged in
+                boolean isLoggedIn = getSession().getAttribute("user") != null;
+                boolean isLoginView = event.getNewView() instanceof SimpleLoginView;
+
+                if (!isLoggedIn && !isLoginView) {
+                    // Redirect to login view always if a user has not yet
+                    // logged in
+                    getNavigator().navigateTo(SimpleLoginView.NAME);
+                    return false;
+
+                } else if (isLoggedIn && isLoginView) {
+                    // If someone tries to access to login view while logged in,
+                    // then cancel
+                    return false;
+                }
+
+                return true;
+            }
+            
+            @Override
+            public void afterViewChange(ViewChangeEvent event) {
+                
+            }
+        });
+    }
+}
diff --git a/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginView.java b/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginView.java
new file mode 100644
index 0000000000..88a2a8f678
--- /dev/null
+++ b/uitest/src/com/vaadin/tests/minitutorials/v70/SimpleLoginView.java
@@ -0,0 +1,137 @@
+package com.vaadin.tests.minitutorials.v70;
+
+import com.vaadin.data.validator.AbstractValidator;
+import com.vaadin.data.validator.EmailValidator;
+import com.vaadin.navigator.View;
+import com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;
+import com.vaadin.shared.ui.MarginInfo;
+import com.vaadin.ui.Alignment;
+import com.vaadin.ui.Button;
+import com.vaadin.ui.Button.ClickEvent;
+import com.vaadin.ui.CustomComponent;
+import com.vaadin.ui.PasswordField;
+import com.vaadin.ui.TextField;
+import com.vaadin.ui.VerticalLayout;
+import com.vaadin.ui.themes.Reindeer;
+
+public class SimpleLoginView extends CustomComponent implements View,
+        Button.ClickListener {
+
+    public static final String NAME = "login";
+
+    private final TextField user;
+
+    private final PasswordField password;
+
+    private final Button loginButton;
+
+    public SimpleLoginView() {
+        setSizeFull();
+
+        // Create the user input field
+        user = new TextField("User:");
+        user.setWidth("300px");
+        user.setRequired(true);
+        user.setInputPrompt("Your username (eg. joe@email.com)");
+        user.addValidator(new EmailValidator("Username must be an email address"));
+        user.setInvalidAllowed(false);
+
+        // Create the password input field
+        password = new PasswordField("Password:");
+        password.setWidth("300px");
+        password.addValidator(new PasswordValidator());
+        password.setRequired(true);
+        password.setValue("");
+        password.setNullRepresentation("");
+
+        // Create login button
+        loginButton = new Button("Login", this);
+
+        // Add both to a panel
+        VerticalLayout fields = new VerticalLayout(user, password, loginButton);
+        fields.setCaption("Please login to access the application. (test@test.com/passw0rd)");
+        fields.setSpacing(true);
+        fields.setMargin(new MarginInfo(true, true, true, false));
+        fields.setSizeUndefined();
+
+        // The view root layout
+        VerticalLayout viewLayout = new VerticalLayout(fields);
+        viewLayout.setSizeFull();
+        viewLayout.setComponentAlignment(fields, Alignment.MIDDLE_CENTER);
+        viewLayout.setStyleName(Reindeer.LAYOUT_BLUE);
+        setCompositionRoot(viewLayout);
+    }
+    
+    @Override
+    public void enter(ViewChangeEvent event) {
+        // focus the username field when user arrives to the login view
+        user.focus();
+    }
+
+    /*
+     * Validator for validating the passwords
+     */
+    private static final class PasswordValidator extends
+            AbstractValidator<String> {
+
+        public PasswordValidator() {
+            super("The password provided is not valid");
+        }
+
+        @Override
+        protected boolean isValidValue(String value) {
+            /*
+             * Password must be at least 8 characters long and contain at least
+             * one number
+             */
+            if (value != null
+                    && (value.length() < 8 || !value.matches(".*\\d.*"))) {
+                return false;
+            }
+            return true;
+        }
+
+        @Override
+        public Class<String> getType() {
+            return String.class;
+        }
+    }
+
+    @Override
+    public void buttonClick(ClickEvent event) {
+
+        /*
+         * Validate the fields using the navigator. By using validors for the
+         * fields we reduce the amount of queries we have to use to the database
+         * for wrongly entered passwords
+         */
+        if (!user.isValid() || !password.isValid()) {
+            return;
+        }
+
+        String username = user.getValue();
+        String password = this.password.getValue();
+
+        /*
+         * Validate username and password with database here. For examples sake
+         * I use a dummy username and password.
+         */
+        boolean isValid = username.equals("test@test.com")
+                && password.equals("passw0rd");
+
+        if(isValid){
+            // Store the current user in the service session
+            getSession().setAttribute("user", username);
+
+            // Navigate to main view
+            getUI().getNavigator().navigateTo(SimpleLoginMainView.NAME);
+
+        } else {
+
+            // Wrong password clear the password field and refocuses it
+            this.password.setValue(null);
+            this.password.focus();
+        }
+    }
+}
+