Fix 5310099: Accept an array of default values for ListPreference.

The reason we want an array of default values is some of them may
be unsupported on a hardware platform. The first supported value
in the array will be used as the default value.

Change-Id: I9e372304ec0eaea3181cf70c352a50b82d4b8c58

1 files changed, 32 insertions, 3 deletions

diff --git a/src/com/android/camera/ListPreference.java b/src/com/android/camera/ListPreference.java
index 6885a37c..32cf692d 100644
--- a/src/com/android/camera/ListPreference.java
+++ b/src/com/android/camera/ListPreference.java
@@ -21,6 +21,7 @@ import android.content.SharedPreferences;
 import android.content.res.TypedArray;
 import android.util.AttributeSet;
 import android.util.Log;
+import android.util.TypedValue;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -33,7 +34,7 @@ public class ListPreference extends CameraPreference {
     private final String TAG = "ListPreference";
     private final String mKey;
     private String mValue;
-    private final String mDefaultValue;
+    private final CharSequence[] mDefaultValues;
 
     private CharSequence[] mEntries;
     private CharSequence[] mEntryValues;
@@ -47,7 +48,20 @@ public class ListPreference extends CameraPreference {
 
         mKey = Util.checkNotNull(
                 a.getString(R.styleable.ListPreference_key));
-        mDefaultValue = a.getString(R.styleable.ListPreference_defaultValue);
+
+        // We allow the defaultValue attribute to be a string or an array of
+        // strings. The reason we need multiple default values is that some
+        // of them may be unsupported on a specific platform (for example,
+        // continuous auto-focus). In that case the first supported value
+        // in the array will be used.
+        int attrDefaultValue = R.styleable.ListPreference_defaultValue;
+        TypedValue tv = a.peekValue(attrDefaultValue);
+        if (tv != null && tv.type == TypedValue.TYPE_REFERENCE) {
+            mDefaultValues = a.getTextArray(attrDefaultValue);
+        } else {
+            mDefaultValues = new CharSequence[1];
+            mDefaultValues[0] = a.getString(attrDefaultValue);
+        }
 
         setEntries(a.getTextArray(R.styleable.ListPreference_entries));
         setEntryValues(a.getTextArray(
@@ -77,12 +91,27 @@ public class ListPreference extends CameraPreference {
 
     public String getValue() {
         if (!mLoaded) {
-            mValue = getSharedPreferences().getString(mKey, mDefaultValue);
+            mValue = getSharedPreferences().getString(mKey,
+                    findSupportedDefaultValue());
             mLoaded = true;
         }
         return mValue;
     }
 
+    // Find the first value in mDefaultValues which is supported.
+    private String findSupportedDefaultValue() {
+        for (int i = 0; i < mDefaultValues.length; i++) {
+            for (int j = 0; j < mEntryValues.length; j++) {
+                // Note that mDefaultValues[i] may be null (if unspecified
+                // in the xml file).
+                if (mEntryValues[j].equals(mDefaultValues[i])) {
+                    return mDefaultValues[i].toString();
+                }
+            }
+        }
+        return null;
+    }
+
     public void setValue(String value) {
         if (findIndexOfValue(value) < 0) throw new IllegalArgumentException();
         mValue = value;