Create the customized TabLayout for the new translate UI

chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateTabLayout.java

Index: chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateTabLayout.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateTabLayout.java b/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateTabLayout.java
index eb684d4eb786c97cae58d79318566777289698d1..5b77a4bc7c64da279ea7c69e418fc103f6a154ee 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateTabLayout.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/infobar/translate/TranslateTabLayout.java
@@ -5,14 +5,21 @@
 package org.chromium.chrome.browser.infobar.translate;
 
 import android.content.Context;
+import android.support.annotation.NonNull;
 import android.support.design.widget.TabLayout;
 import android.util.AttributeSet;
+import android.view.LayoutInflater;
+import android.view.MotionEvent;
+
+import org.chromium.chrome.R;
 
 /**
- * Lays out an infobar that has all of its controls along a line.
- * It's currently used for Translate UI redesign only.
+ * TabLayout shown in the TranslateCompactInfoBar.
  */
 public class TranslateTabLayout extends TabLayout {
+    // The tab in which a spinning progress bar is showing.
+    private Tab mTabShowingProgressBar;
+
     /**
      * Constructor for inflating from XML.
      */
@@ -20,5 +27,127 @@ public class TranslateTabLayout extends TabLayout {
         super(context, attrs);
     }
 
-    // TODO(martiw): Add special methods on demand.
+    /**
+     * Add new Tabs with title strings.
+     * @param titles Titles of the tabs to be added.
+     */
+    public void addTabs(CharSequence... titles) {
+        for (CharSequence title : titles) {
+            addTabWithTitle(title);
+        }
+    }
+
+    /**
+     * Add a new Tab with the title string.
+     * @param tabTitle Title string of the new tab.
+     */
+    public void addTabWithTitle(CharSequence tabTitle) {
+        TranslateTabContent tabContent =
+                (TranslateTabContent) LayoutInflater.from(getContext())
+                        .inflate(R.layout.infobar_translate_tab_content, this, false);
+        // Set text color using tabLayout's ColorStateList.  So that the title text will change
+        // color when selected and unselected.
+        tabContent.setTextColor(getTabTextColors());
+        tabContent.setText(tabTitle);
+
+        Tab tab = newTab();
+        tab.setCustomView(tabContent);
+        tab.setContentDescription(tabTitle);
+        super.addTab(tab);
+    }
+
+    /**
+     * Replace the title string of a tab.
+     * @param tabPos   The position of the tab to modify.
+     * @param tabTitle The new title string.
+     */
+    public void replaceTabTitle(int tabPos, CharSequence tabTitle) {
+        if (tabPos < 0 || tabPos >= getTabCount()) {
+            return;
+        }
+        Tab tab = getTabAt(tabPos);
+        ((TranslateTabContent) tab.getCustomView()).setText(tabTitle);
+        tab.setContentDescription(tabTitle);
+    }
+
+    /**
+     * Select a tab.
+     * @param tabPos The position of the tab to select.
+     */
+    public void selectTab(int tabPos) {
+        if (tabPos < 0 || tabPos >= getTabCount() || mTabShowingProgressBar != null) {
+            return;
+        }
+        getTabAt(tabPos).select();
+    }
+
+    /**
+     * Show the spinning progress bar on a specified tab.
+     * @param tabPos The position of the tab to show the progress bar.
+     */
+    public void showProgressBarOnTab(int tabPos) {
+        if (tabPos < 0 || tabPos >= getTabCount() || mTabShowingProgressBar != null) {
+            return;
+        }
+        mTabShowingProgressBar = getTabAt(tabPos);
+
+        mTabShowingProgressBar.select();
+
+        // TODO(martiw) See if we need to setContentDescription as "Translating" here.
+
+        if (tabIsSupported(mTabShowingProgressBar)) {
+            ((TranslateTabContent) mTabShowingProgressBar.getCustomView()).showProgressBar();
+        }
+    }
+
+    /** Stop the spinning progress bar. */
+    public void stopProgressBarAndRevertBack() {
+        if (mTabShowingProgressBar == null) {
+            return;
+        }
+
+        // TODO(martiw) if we have setContentDescription at showProgressBarOnTab(), we need to
+        // revert it here.
+
+        if (tabIsSupported(mTabShowingProgressBar)) {
+            ((TranslateTabContent) mTabShowingProgressBar.getCustomView()).hideProgressBar();
+        }
+        // TODO(martiw) See if we need to prevent the following from triggering onTabSelected event.
+        selectTab(0); // switch the selection back to the first tab.
+
+        mTabShowingProgressBar = null;
+    }
+
+    // Overrided to block children's touch event when showing progress bar.
+    @Override
+    public boolean onInterceptTouchEvent(MotionEvent ev) {
+        // Allow touches to propagate to children only if the layout can be interacted with.
+        if (mTabShowingProgressBar != null) {
+            return true;
+        }
+        return super.onInterceptTouchEvent(ev);
+    }
+
+    /** Check if the tab is supported in TranslateTabLayout. */
+    private boolean tabIsSupported(Tab tab) {
+        return (tab.getCustomView() instanceof TranslateTabContent);
+    }
+
+    // Overrided to make sure only supported Tabs can be added.
+    @Override
+    public void addTab(@NonNull Tab tab, int position, boolean setSelected) {
+        if (!tabIsSupported(tab)) {
+            throw new IllegalArgumentException();
+        }
+        super.addTab(tab, position, setSelected);
+    }
+
+    // Overrided to make sure only supported Tabs can be added.
+    @Override
+    public void addTab(@NonNull Tab tab, boolean setSelected) {
+        if (!tabIsSupported(tab)) {
+            throw new IllegalArgumentException();
+        }
+        super.addTab(tab, setSelected);
+    }
 }