TagView

Compare view resources in easy way by just their ids, especially handy in yor Espresso tests.

An android widget like TextView usually do not hold a reference to the drawable resources you set to them. It can be a trouble if you want to assert that view displays correct drawables. You can do that in several ways: compare raw bitmaps bitmap.sameAs() or set a custom tag with resource id to retrieve it later in your tests. This library can help you to automate the second approach.

Approach here based on using a custom inflater. Pretty much the same as Calligraphy does. Some predefined tags are set to the inflated by the custom LayoutInflater views.

Getting started

Dependency

Add jcenter() to repositories block in your gradle file.
Add implementation 'com.shuhart.tagview:tagview:1.0.3' to your dependencies.

Usage

Configure the library in your Application class:

TagViewConfig.initDefault(new TagViewConfig.Builder()
        .build());

Wrap the Activity Context

@Override
protected void attachBaseContext(Context newBase) {
    super.attachBaseContext(TagViewContextWrapper.wrap(newBase));
}

Thats it! Now you can retrieve some useful tags in your Espresso tests:

onView(withId(R.id.textview)).check(assertTagKeyValue(ViewTag.TEXTVIEW_DRAWABLE_LEFT.id, android.R.drawable.ic_delete));
onView(withId(R.id.textview)).check(assertTagKeyValue(ViewTag.TEXTVIEW_DRAWABLE_TOP.id, android.R.drawable.ic_btn_speak_now));
onView(withId(R.id.textview)).check(assertTagKeyValue(ViewTag.TEXTVIEW_DRAWABLE_RIGHT.id, android.R.drawable.ic_input_add));
onView(withId(R.id.textview)).check(assertTagKeyValue(ViewTag.TEXTVIEW_DRAWABLE_BOTTOM.id, android.R.drawable.ic_input_get));
onView(withId(R.id.frame)).check(assertTagKeyValue(ViewTag.VIEW_BACKGROUND.id, R.color.colorPrimary));
onView(withId(R.id.frame)).check(assertTagKeyValue(ViewTag.VIEW_FOREGROUND.id, getSelectableItemBackgroundId(context)));
onView(withId(R.id.imageview)).check(assertTagKeyValue(ViewTag.IMAGEVIEW_SRC.id, android.R.drawable.ic_media_play));

You can find usage example in ExampleInstrumentedTest

A convenient espresso matcher and assertion ViewTagMatchers are used.

Tagging in runtime

If you create a widget in runtime not using the xml inflation then you can use TagViewUtils when you want to set a TextView drawable or else:

setBackground(View view, int id)
clearBackground(View view)
setForeground(View view, int id)
clearForeground(View view)
setTextViewCompoundDrawablesRelativeWithIntrinsicBounds(TextView view, int left, int top, int right, int bottom)
setTextViewCompoundDrawables(TextView view, int left, int top, int right, int bottom)
setImageViewResource(ImageView view, int id)
setTag(View view, int key, int id)

In this case tagging is done for you internally.
If you use Kotlin you can write a handy extensions to call view itself. Something like this:

fun ImageView.setImageResourceWithTag(@param:DrawableRes int id) {
    TagViewUtils.setImageViewResource(this, id)
}

Predefined tags

Tag key (R.id)	Description
tagview_view_background	`android:backgrond`
tagview_view_foreground	`android:foreground`
tagview_textview_drawable_left	TextView `android:drawableLeft or andorid:drawableStart`
tagview_textview_drawable_top	TextView `android:drawableTop`
tagview_textview_drawable_right	TextView `android:drawableRight or android:drawableEnd`
tagview_textview_drawable_bottom	TextView `android:drawableBottom`
tagview_imageview_src	ImageView `android:src`

You can retrieve any tag by calling TagViewUtils.getTag(View view, @IdRes int key):

TagViewUtils.getTag(view, ViewTag.VIEW_BACKGROUND.id)

Custom attributes

If you want to support this feature for your custom views or any other not mentioned andorid widget attributes you can do it:

Add you custom attribute and a tag key for it in TagViewConfig:

TagViewConfig.initDefault(new TagViewConfig.Builder()
        .addAttributeTag(com.rengwuxian.materialedittext.R.attr.met_iconLeft, R.id.met_icon_left)
        .build());

UI test:

onView(withId(R.id.met_edittext)).check(assertTagKeyValue(R.id.met_icon_left, android.R.drawable.ic_secure));

Any tag key for a view must be defined as id in xml. This is Android SDK requirement. See android.view.View#setTag(int, Object)

No reflection way

If you for some reason do not want the library use reflection to inject a custom layout inflation factory you can use another approach. This could come in handy if you use some other libraries to override views inflation mechanism (like Calligraphy):

You need to disable reflection:

TagViewConfig.initDefault(new TagViewConfig.Builder()
        .addAttributeTag(com.rengwuxian.materialedittext.R.attr.met_iconLeft, R.id.met_icon_left)
        .disablePrivateFactoryInjection() // no private factory injection takes place
        .build());

Then you need to override Activity#onCreateView(String, Context, AttributeSet) and delegate a view created by system inflater to the library:

@Override
public View onCreateView(View parent, String name, Context context, AttributeSet attrs) {
    View view = super.onCreateView(parent, name, context, attrs);
    return TagViewContextWrapper.onActivityCreateView(this, parent, view, name, context, attrs);
}

License

Copyright 2018 Bogdan Kornev.

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.

shuhart / TagView