PaginationManager

PaginationManager makes it easy to add paging functionality to any kind of scrollView.

##Compatibility:
PaginationManager is only compatible with Swift 2.3. Swift 3.0 support comming soon.

##Installation:
####CocoaPods

• Add the following to your Podfile

  pod 'PaginationManager'

• Run pod install

####Manual

• Copy PaginationManager.swift into your project

##Usage:
If you are using CocoaPods, you need to import PaginationManager as a module to your class by adding the following:

import PaginationManager

####Declaration
You need to create a PaginationManager property (you need a strong reference):

var paginationManager: PaginationManager?

####Initialization
PaginationManager provides two initializers:

–

init(scrollView:direction:thresholdType:)

• scrollView
  The scrollView for the pagination manager

• direction
  The direction of the scrollView

• thresholdType
  The thresholdType for the pagination manager. This has a default value of .constant(value: PaginationManagerConstantThresholdScreenDimension). See Types of threshold below.

Use the first initializer if you want to hook into the scrollView’s delegate methods. This will set the PaginationManager as the delegate of the scrollView and pass the delegate methods to the original delegate.

–

init(direction:thresholdType:)

• direction
  The direction of the scrollView

• thresholdType
  The thresholdType for the pagination manager. This has a default value of .constant(value: PaginationManagerConstantThresholdScreenDimension). See Customization below.

If you use the this initializer, you need to explicitly call scrollViewDidScroll: on the PaginationManager at your scrollView’s scrollViewDidScroll: delegate callback.

–

PaginationManager also includes the following static initializers for objective-c interoperability.

constantThresholdManager(forScrollView:direction:constant:)
constantThresholdManager(withDirection:constant:)
percentageThresholdManager(forScrollView:direction:percentage:)
percentageThresholdManager(withDirection:percentage:)

####Delegation

You also need to assign the delegate of the PaginationManager, like so:

paginationManager?.delegate = self

Also make sure to conform to the PaginationManagerDelegate:

func paginationManagerDidExceedThreshold(manager: PaginationManager, reset: PaginationManagerResetBlock)

See Delegate callback below.

##Customization:
You can customize the behavior of the pagination manager by the following:

####PaginationManagerDirection : enum
You need to provide a scroll direction for the pagination manager during initialization. This cannot be modified later on as the core behavior of the pagination manager depends on it.

####PaginationManagerThresholdType : enum
This property governs the threshold type for the PaginationManager. It provides the following types of thresholds:

• percentage(value:)

This type defines a threshold based on the percentage scrolled. It takes in a percentage value. This value should be between 0.0 and 1.0.

• constant(value:)

This type defines a threshold based on a constant amount from the end of the scrollView’s content. It requires a constant value. This value should be greater than 0.0. This is the default type for the PaginationManager and its default value is defined as PaginationManagerConstantThresholdScreenDimension which takes the maximum device screen dimension based on the direction of the PaginationManager.

##Delegate callback:
The PaginationManagerDelegate provides only one method:

func paginationManagerDidExceedThreshold(manager: PaginationManager, reset: PaginationManagerResetBlock)

This is a required method. At the end of your implementation for this, you must call the reset block. This block takes a bool value that tells the manager whether new items were loaded or not. An example could be loading async images and then calling reset(true) when new images are loaded. This system of calling the reset block is implemented to restrict the manager from notifiying the receiver multiple times.

##Example:
An example project has been included. It contains a basic implementation of the PaginationManager

Issues / PRs welcome 😃

##License

MIT License

Copyright © 2016 Taimur Ayaz

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the “Software”), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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