Add context extensions for getBoolean, getInteger, getDimension.

api/current.txt

@@ -23,6 +23,9 @@ package androidx.core.content {
 
   public final class ContextKt {
     ctor public ContextKt();
+    method public static boolean getBoolean(android.content.Context, @BoolRes int id) throws android.content.res.Resources.NotFoundException;
+    method public static float getDimension(android.content.Context, @DimenRes int id) throws android.content.res.Resources.NotFoundException;
+    method public static int getInteger(android.content.Context, @IntegerRes int id) throws android.content.res.Resources.NotFoundException;
     method public static void withStyledAttributes(android.content.Context, android.util.AttributeSet? set = "null", int[] attrs, @AttrRes int defStyleAttr = "0", @StyleRes int defStyleRes = "0", kotlin.jvm.functions.Function1<? super android.content.res.TypedArray,kotlin.Unit> block);
     method public static void withStyledAttributes(android.content.Context, @StyleRes int resourceId, int[] attrs, kotlin.jvm.functions.Function1<? super android.content.res.TypedArray,kotlin.Unit> block);
   }

src/androidTest/java/androidx/core/content/ContextTest.kt

@@ -16,13 +16,16 @@
 
 package androidx.core.content
 
+import android.content.res.Resources
 import android.support.test.InstrumentationRegistry
 import android.support.test.filters.SdkSuppress
 import android.test.mock.MockContext
 import androidx.core.kotlin.test.R
+import androidx.testutils.assertThrows
 import androidx.testutils.getAttributeSet
 import org.junit.Assert.assertEquals
 import org.junit.Assert.assertSame
+import org.junit.Assert.assertFalse
 import org.junit.Assert.assertTrue
 import org.junit.Test
 
@@ -69,5 +72,22 @@ class ContextTest {
         context.withStyledAttributes(attrs, R.styleable.SampleAttrs, 0, 0) {
             assertTrue(getInt(R.styleable.SampleAttrs_sample, -1) != -1)
         }
+
+        assertEquals(context.getInteger(R.integer.integer_25), 25)
+        assertThrows< Resources.NotFoundException> {
+            context.getInteger(-1)
+        }
+
+        assertTrue(context.getBoolean(R.bool.bool_true))
+        assertFalse(context.getBoolean(R.bool.bool_false))
+        assertThrows< Resources.NotFoundException> {
+            context.getBoolean(-1)
+        }
+
+        assertEquals(context.getDimension(R.dimen.dimen_25),
+            25f * context.resources.displayMetrics.density)
+        assertThrows< Resources.NotFoundException> {
+            context.getDimension(-1)
+        }
     }
 }

src/androidTest/res/values/booleans.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2018 The Android Open Source Project
+  ~
+  ~ 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.
+  -->
+
+<resources>
+    <bool name="bool_true">true</bool>
+    <bool name="bool_false">false</bool>
+</resources>

src/androidTest/res/values/dimens.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2018 The Android Open Source Project
+  ~
+  ~ 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.
+  -->
+
+<resources>
+    <dimen name="dimen_25">25dp</dimen>
+</resources>

src/androidTest/res/values/integers.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  ~ Copyright (C) 2018 The Android Open Source Project
+  ~
+  ~ 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.
+  -->
+
+<resources>
+    <integer name="integer_25">25</integer>
+</resources>

src/main/java/androidx/core/content/Context.kt

@@ -14,11 +14,17 @@
  * limitations under the License.
  */
 
+@file:Suppress("NOTHING_TO_INLINE") // Aliases to public API.
+
 package androidx.core.content
 
 import android.content.Context
+import android.content.res.Resources
 import android.content.res.TypedArray
 import android.support.annotation.AttrRes
+import android.support.annotation.BoolRes
+import android.support.annotation.DimenRes
+import android.support.annotation.IntegerRes
 import android.support.annotation.RequiresApi
 import android.support.annotation.StyleRes
 import android.util.AttributeSet
@@ -91,3 +97,53 @@ inline fun Context.withStyledAttributes(
         typedArray.recycle()
     }
 }
+
+/**
+ * Return a boolean associated with a particular resource ID.  This can be
+ * used with any integral resource value, and will return true if it is
+ * non-zero.
+ *
+ * @param id The desired resource identifier, as generated by the aapt
+ *           tool. This integer encodes the package, type, and resource
+ *           entry. The value 0 is an invalid identifier.
+ *
+ * @throws android.content.res.Resources.NotFoundException Throws NotFoundException if the given ID does not exist.
+ *
+ * @return Returns the boolean value contained in the resource.
+ */
+@Throws(Resources.NotFoundException::class)
+inline fun Context.getBoolean(@BoolRes id: Int) = resources.getBoolean(id)
+
+/**
+ * Return an integer associated with a particular resource ID.
+ *
+ * @param id The desired resource identifier, as generated by the aapt
+ *           tool. This integer encodes the package, type, and resource
+ *           entry. The value 0 is an invalid identifier.
+ *
+ * @throws android.content.res.Resources.NotFoundException Throws NotFoundException if the given ID does not exist.
+ *
+ * @return Returns the integer value contained in the resource.
+ */
+@Throws(Resources.NotFoundException::class)
+inline fun Context.getInteger(@IntegerRes id: Int) = resources.getInteger(id)
+
+/**
+ * Retrieve a dimensional for a particular resource ID.  Unit
+ * conversions are based on the current {@link DisplayMetrics} associated
+ * with the resources.
+ *
+ * @param id The desired resource identifier, as generated by the aapt
+ *           tool. This integer encodes the package, type, and resource
+ *           entry. The value 0 is an invalid identifier.
+ *
+ * @return Resource dimension value multiplied by the appropriate
+ * metric.
+ *
+ * @throws Resources.NotFoundException Throws NotFoundException if the given ID does not exist.
+ *
+ * @see android.content.res.Resources.getDimensionPixelOffset
+ * @see android.content.res.Resources.getDimensionPixelSize
+ */
+@Throws(Resources.NotFoundException::class)
+inline fun Context.getDimension(@DimenRes id: Int) = resources.getDimension(id)