Add type definition file

Author: droibit

package.json

@@ -27,6 +27,7 @@
     "react-native": "*",
     "react": "*"
   },
+  "types": "src/index.d.ts",
   "devDependencies": {
     "@types/react": "^16.4.6",
     "@types/react-native": "^0.55.27",

src/index.d.ts

@@ -0,0 +1,83 @@
+/**
+ * Utility class for opening http or https URL in Custom Tabs.
+ */
+export class CustomTabs {
+
+  /**
+   * Opens the URL on Custom Tab.
+   *
+   * @param url the Uri to be opened.
+   * @param option the Option to customize Custom Tabs of look & feel.
+   */
+  static openURL(url: string, option: TabOption = {}): Promise<boolean>;
+}
+
+/**
+ * Options to customize Custom Tabs of look & feel.
+ */
+export interface TabOption {
+
+  /**
+   * the Toolbar color.
+   * Supported formats are: #RRGGBB, #AARRGGBB, etc.
+   *
+   * {@link http://d.android.com/reference/android/graphics/Color.html#parseColor(java.lang.String) Color.parseColor(String)}
+   */
+  toolbarColor?: string;
+
+  /**
+   * Enables the url bar to hide as the user scrolls down on the page.
+   */
+  enableUrlBarHiding?: boolean;
+
+  /**
+   * Sets whether the title should be shown in the custom tab.
+   */
+  showPageTitle?: boolean;
+
+  /**
+   * Whether to add a default shared items of the menu.
+   */
+  enableDefaultShare?: boolean;
+
+  /**
+   * Sets the exit and start animations.
+   *
+   * Each property needs to be an Andrion animation resource ID,
+   * e.g. 'com.github.droibit.android.reactnative.customtabs.example:anim/slide_out_bottom'
+   *
+   * @see ANIMATIONS_FADE
+   * @see ANIMATIONS_SLIDE
+   */
+  animations?: Animations;
+
+  /**
+   * Sets any custom headers that should be used.
+   */
+  headers?: any;
+
+  /**
+   * Workaround that Custom Tabs doesn't close on redirecting back to app scheme.
+   */
+  forceCloseOnRedirection?: boolean;
+}
+
+/**
+ * Custom Tabs start and end Animation.
+ */
+export interface Animations {
+  startEnter: string;
+  startExit: string;
+  endEnter: string;
+  endExit: string; 
+}
+
+/**
+ * Fade in at start, Fade out at exit.
+ */
+export const ANIMATIONS_FADE: Animations;
+
+/**
+ * Slide in from left at start, Slide out to right.at exit.
+ */
+export const ANIMATIONS_SLIDE: Animations;