Fix #674 Parse colors with alpha channel

Signed-off-by: Stefan Niedermann <info@niedermann.it>
stefan-niedermann · Sep 3, 2020 · c24621a · c24621a
1 parent 6ccf215
commit c24621a
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Showing 2 changed files with 29 additions and 7 deletions.
diff --git a/app/src/androidTest/java/it/niedermann/nextcloud/deck/util/ColorUtilTest.java b/app/src/androidTest/java/it/niedermann/nextcloud/deck/util/ColorUtilTest.java
@@ -111,6 +111,11 @@ public void testGetCleanHexaColorString() {
  validColors.add(new Pair<>("ccc", "#cccccc"));
  validColors.add(new Pair<>("af0", "#aaff00"));
  validColors.add(new Pair<>("#af0", "#aaff00"));
+ // Strip alpha channel (https://github.com/stefan-niedermann/nextcloud-deck/issues/674)
+ validColors.add(new Pair<>("af05", "#aaff00"));
+ validColors.add(new Pair<>("#af05", "#aaff00"));
+ validColors.add(new Pair<>("aaff0055", "#aaff00"));
+ validColors.add(new Pair<>("#aaff0055", "#aaff00"));
  for (Pair<String, String> color : validColors) {
  assertEquals("Expect " + color.first + " to be cleaned up to " + color.second, color.second, ColorUtil.formatColorToParsableHexString(color.first));
  }

diff --git a/app/src/main/java/it/niedermann/nextcloud/deck/util/ColorUtil.java b/app/src/main/java/it/niedermann/nextcloud/deck/util/ColorUtil.java
@@ -7,6 +7,7 @@
 import androidx.annotation.Nullable;
 import androidx.core.util.Pair;
 
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 
@@ -47,14 +48,30 @@ public static String formatColorToParsableHexString(String input) {
  }
  final char[] chars = input.replaceAll("#", "").toCharArray();
  final StringBuilder sb = new StringBuilder(7).append("#");
- if (chars.length == 6) {
- sb.append(chars);
- } else if (chars.length == 3) {
- for (char c : chars) {
- sb.append(c).append(c);
+ switch (chars.length) {
+ case 8: { // Strip alpha channel
+ sb.append(Arrays.copyOfRange(chars, 0, 6));
+ break;
+ }
+ case 6: { // Default long
+ sb.append(chars);
+ break;
+ }
+ case 4: { // Strip alpha channel
+ for (char c : Arrays.copyOfRange(chars, 0, 3)) {
+ sb.append(c).append(c);
+ }
+ break;
+ }
+ case 3: { // Default short
+ for (char c : chars) {
+ sb.append(c).append(c);
+ }
+ break;
+ }
+ default: {
+ throw new IllegalArgumentException("unparsable color string: \"" + input + "\"");
  }
- } else {
- throw new IllegalArgumentException("unparsable color string: \"" + input + "\"");
  }
  final String formattedHexColor = sb.toString();
  if (isParsableValidHexColorString(formattedHexColor)) {