菜单项动画，无限旋转其自定义图标

Question

我有一个带有图标的菜单项（例如，带有一个刺血针的时钟），我想使其图标无限期旋转。

我该如何管理这种效果？谢谢。

Answer 1

添加文件res/layout/iv_refresh.xml（用您的自定义图标替换ic_launcher）：

<?xml version="1.0" encoding="utf-8"?>
<ImageView
    xmlns:android="http://schemas.android.com/apk/res/android"
    style="@android:style/Widget.ActionButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:contentDescription="@string/app_name"
    android:src="@drawable/ic_launcher" />

添加文件res/anim/rotate_refresh.xml：

<?xml version="1.0" encoding="utf-8"?>
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="1000"
    android:fromDegrees="0"
    android:interpolator="@android:anim/linear_interpolator"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toDegrees="360">
</rotate>

最后，您可以在Java代码中像这样开始动画：

LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
ImageView iv = (ImageView)inflater.inflate(R.layout.iv_refresh, null);
Animation rotation = AnimationUtils.loadAnimation(this, R.anim.rotate_refresh);
rotation.setRepeatCount(Animation.INFINITE);
iv.startAnimation(rotation);
menu.findItem(R.id.my_menu_item_id).setActionView(iv);

Answer 2

最好的方法在这里：

public class HomeActivity extends AppCompatActivity {
    public static ActionMenuItemView btsync;
    public static RotateAnimation rotateAnimation;

@Override
protected void onCreate(Bundle savedInstanceState) {
    rotateAnimation = new RotateAnimation(360, 0, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);
    rotateAnimation.setDuration((long) 2*500);
    rotateAnimation.setRepeatCount(Animation.INFINITE);

然后：

private void sync() {
    btsync = this.findViewById(R.id.action_sync); //remember that u cant access this view at onCreate() or onStart() or onResume() or onPostResume() or onPostCreate() or onCreateOptionsMenu() or onPrepareOptionsMenu()
    if (isSyncServiceRunning(HomeActivity.this)) {
        showConfirmStopDialog();
    } else {
        if (btsync != null) {
            btsync.startAnimation(rotateAnimation);
        }
        Context context = getApplicationContext();
        context.startService(new Intent(context, SyncService.class));
    }
}

记住您无法访问“ btsync = this.findViewById（R.id.action_sync）;”在onCreate（）或onStart（）或onResume（）或onPostResume（）或onPostCreate（）或onCreateOptionsMenu（）或onPrepareOptionsMenu（）如果您想在活动开始后立即获取它，则将其放在后延迟的位置：

public static void refreshSync(Activity context) {
    Handler handler = new Handler(Looper.getMainLooper());
    handler.postDelayed(new Runnable() {
        public void run() {
            btsync = context.findViewById(R.id.action_sync);
            if (btsync != null && isSyncServiceRunning(context)) {
                btsync.startAnimation(rotateAnimation);
            } else if (btsync != null) {
                btsync.clearAnimation();
            }
        }
    }, 1000);
}