Android-ObservableScrollView

Android library to observe scroll events on scrollable views.
It's easy to interact with the Toolbar introduced in Android 5.0 Lollipop and may be helpful to implement look and feel of Material Design apps.

Installation

dependencies {
    compile 'com.github.ksoichiro:android-observablescrollview:1.2.0'
}

Samples

See observablescrollview-samples directory.

To install:

$ ./gradlew installDebug

Supported widgets

Widget	Since	Note
ListView	v1.0.0
ScrollView	v1.0.0
WebView	v1.0.0
RecyclerView	v1.1.0	It's supported but RecyclerView provides scroll states and position with OnScrollListener. You should use it if you don't have any reason.
GridView	v1.2.0

How to use

Add widgets to your layout

Use one of the ObservableListView, ObservableScrollView, ObservableWebView, ObservableRecyclerView in your XML layout file.

Control scroll events with callbacks

Widgets above provides callbacks with ObservableScrollViewCallbacks interface.
You can listen scroll events of the widgets by using setScrollViewCallbacks().

    ObservableListView listView = (ObservableListView) findViewById(R.id.list);
    listView.setScrollViewCallbacks(this);

Then implement your interaction codes to the callbacks.
Example:

    @Override
    public void onUpOrCancelMotionEvent(ScrollState scrollState) {
        ActionBar ab = getSupportActionBar();
        if (scrollState == ScrollState.UP) {
            if (ab.isShowing()) {
                ab.hide();
            }
        } else if (scrollState == ScrollState.DOWN) {
            if (!ab.isShowing()) {
                ab.show();
            }
        }
    }

See sample project's Activity codes for more details.

Developed By

• Soichiro Kashima - soichiro.kashima@gmail.com

Credits

• Inspired by ObservableScrollView in romannurik-code.

License

Copyright 2014 Soichiro Kashima

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.