1 package android.support.v17.leanback.widget; 2 3 import android.graphics.drawable.Drawable; 4 import android.os.Build; 5 import android.view.View; 6 7 final class ForegroundHelper { 8 9 final static ForegroundHelper sInstance = new ForegroundHelper(); 10 ForegroundHelperVersionImpl mImpl; 11 12 /** 13 * Interface implemented by classes that support Shadow. 14 */ 15 static interface ForegroundHelperVersionImpl { 16 17 public void setForeground(View view, Drawable drawable); 18 19 public Drawable getForeground(View view); 20 } 21 22 /** 23 * Implementation used on api 23 (and above). 24 */ 25 private static final class ForegroundHelperApi23Impl implements ForegroundHelperVersionImpl { 26 ForegroundHelperApi23Impl() { 27 } 28 29 @Override 30 public void setForeground(View view, Drawable drawable) { 31 ForegroundHelperApi23.setForeground(view, drawable); 32 } 33 34 @Override 35 public Drawable getForeground(View view) { 36 return ForegroundHelperApi23.getForeground(view); 37 } 38 } 39 40 /** 41 * Stub implementation 42 */ 43 private static final class ForegroundHelperStubImpl implements ForegroundHelperVersionImpl { 44 ForegroundHelperStubImpl() { 45 } 46 47 @Override 48 public void setForeground(View view, Drawable drawable) { 49 } 50 51 @Override 52 public Drawable getForeground(View view) { 53 return null; 54 } 55 } 56 57 private ForegroundHelper() { 58 if (supportsForeground()) { 59 mImpl = new ForegroundHelperApi23Impl(); 60 } else { 61 mImpl = new ForegroundHelperStubImpl(); 62 } 63 } 64 65 public static ForegroundHelper getInstance() { 66 return sInstance; 67 } 68 69 /** 70 * Returns true if view.setForeground() is supported. 71 */ 72 public static boolean supportsForeground() { 73 return Build.VERSION.SDK_INT >= 23; 74 } 75 76 public Drawable getForeground(View view) { 77 return mImpl.getForeground(view); 78 } 79 80 public void setForeground(View view, Drawable drawable) { 81 mImpl.setForeground(view, drawable); 82 } 83 } 84
