本文主要实现功能，可能有不合理的地方
首先创建一个实现功能的工具里，直接上代码：
import android.content.Context;import android.graphics.Bitmap;import android.os.Handler;import android.os.Message;import com.android.launcher3.ItemInfo;import com.android.launcher3.LauncherSettings;import com.android.launcher3.ShortcutInfo;import com.android.launcher3.util.LogUtil;public class DeskClockUtil { private OnDeskClockIconChangeListener mListener; private ItemInfo mItemInfo; private boolean mIsResume; private Handler mHandler = new Handler() { @Override public void handleMessage(Message msg) { super.handleMessage(msg); if (msg.what == 100) { Message msg1 = new Message(); msg1.what = 100; msg1.obj = msg.obj; mHandler.sendMessageDelayed(msg1, 60000); if (mListener != null && mItemInfo != null) { mListener.onChange(IconUtil.getDeskClockIcon((Context) msg.obj), mItemInfo); } } } }; private static DeskClockUtil sInstance; private DeskClockUtil() { } public static DeskClockUtil getInstance() { if (sInstance == null) { sInstance = new DeskClockUtil(); } return sInstance; } private void refresh(Context context) { if (mListener != null && mItemInfo != null) { mListener.onChange(IconUtil.getDeskClockIcon(context), mItemInfo); } if (mHandler.hasMessages(100)) { mHandler.removeMessages(100); } Message msg = new Message(); msg.what = 100; msg.obj = context; mHandler.sendMessageDelayed(msg, 1000 * (60 - Integer.parseInt(DateUtils.getCurrentSecond()))); } public void onResume(Context context) { mIsResume = true; refresh(context); } public void onPause() { mIsResume = false; mHandler.removeMessages(100); } public void setListener(OnDeskClockIconChangeListener listener, ItemInfo info, Context context) { if (!(info instanceof ShortcutInfo)) { return; } String pkg = null; if (info.getIntent() != null && info.getIntent().getComponent() != null) { pkg = info.getIntent().getComponent().getPackageName(); } if (!"com.android.deskclock".equals(pkg) || info.itemType == LauncherSettings.Favorites.ITEM_TYPE_DEEP_SHORTCUT) { return; } mListener = listener; mItemInfo = info; if (mIsResume) { refresh(context); } } public interface OnDeskClockIconChangeListener { void onChange(Bitmap icon, ItemInfo info); }} 画出动态时钟
import android.content.Context;import android.graphics.*;import com.android.launcher3.R;public class IconUtil { private static final String TAG = "IconUtil"; private static Bitmap getBitmap(Context context, int res) { BitmapFactory.Options options = new BitmapFactory.Options(); options.inPreferredConfig = Bitmap.Config.ARGB_4444; return BitmapFactory.decodeResource(context.getResources(), res, options); } public static Bitmap getDeskClockIcon(Context context) { // 添加一个带表盘的背景图 Bitmap empty = getBitmap(context, R.drawable.icon_time); int x = empty.getWidth(); int y = empty.getHeight(); Bitmap deskClock = Bitmap.createBitmap(x, y, Bitmap.Config.ARGB_4444); Canvas canvas = new Canvas(deskClock); Paint paint = new Paint(); paint.setAntiAlias(true); canvas.drawBitmap(empty, 0, 0, paint); //设置圆角 paint.setStrokeCap(Paint.Cap.ROUND); paint.setStrokeWidth(5); paint.setColor(context.getResources().getColor(R.color.deskclock_time)); // 时针的长度 int radius = 35; // 圆心的x y 坐标 int cx = x / 2; int cy = y / 2; int hour = Integer.parseInt(DateUtils.getCurrentHour()); int min = Integer.parseInt(DateUtils.getCurrentMin()); //时针的角度，这里是整点的角度。因为0°是从3点开始，所以这里减90°，从9点开始计算角度 int drgeeHour = hour * 30 - 90; if (drgeeHour < 0) { drgeeHour += 360; } // 加上时针在两个整点之间的角度，一分钟在分针上是6°，在时针上是min * 6 / 12 drgeeHour += min * 6 / 12; //时针 针尖的x y坐标，相当于已知圆心坐标和半径，求圆上任意一点的坐标 int xHour = (int) (cx + radius * Math.cos(drgeeHour * 3.14 / 180)); int yHour = (int) (cy + radius * Math.sin(drgeeHour * 3.14 / 180)); canvas.drawLine(xHour, yHour, cx, cy, paint); //分针的长度 radius = 45; paint.setStrokeWidth(3); paint.setColor(Color.RED); //分针的角度 int drgeeMin = min * 6 - 90; if (drgeeMin < 0) { drgeeMin += 360; } //分针 针尖的x y坐标 int x1 = (int) (cx + radius * Math.cos(drgeeMin * Math.PI / 180)); int y1 = (int) (cy + radius * Math.sin(drgeeMin * Math.PI / 180)); canvas.drawLine(x1, y1, cx, cy, paint); return deskClock; }} 时间工具类
import java.text.SimpleDateFormat;public class DateUtils { public static String getCurrentDay() { SimpleDateFormat format = new SimpleDateFormat("dd"); Long t = new Long(System.currentTimeMillis()); String d = format.format(t); return d; } public static String getCurrentSecond() { SimpleDateFormat format = new SimpleDateFormat("ss"); Long t = new Long(System.currentTimeMillis()); String d = format.format(t); return d; } public static String getCurrentMin() { SimpleDateFormat format = new SimpleDateFormat("mm"); Long t = new Long(System.currentTimeMillis()); String d = format.format(t); return d; } public static String getCurrentHour() { SimpleDateFormat format = new SimpleDateFormat("HH"); Long t = new Long(System.currentTimeMillis()); String d = format.format(t); return d; }} 下面就比较简单了，我是在BubbleTextView.java中添加listener，我这里偷懒了，应该给时钟单独创建一个view，继承BubbleTextView。
private void applyIconAndLabel(Bitmap icon, ItemInfo info) { /* begin */ setDeskClockIcon(info); /* end */ applyIcon(icon, info); setText(info.title); if (info.contentDescription != null) { setContentDescription(info.isDisabled() ? getContext().getString(R.string.disabled_app_label, info.contentDescription) : info.contentDescription); } } private void setDeskClockIcon(ItemInfo info) { DeskClockUtil.getInstance().setListener(new DeskClockUtil.OnDeskClockIconChangeListener() { @Override public void onChange(Bitmap icon, ItemInfo info) { applyIcon(icon, info); } }, info, getContext()); } private void applyIcon(Bitmap icon, ItemInfo info) { FastBitmapDrawable iconDrawable = DrawableFactory.get(getContext()).newIcon(icon, info); iconDrawable.setIsDisabled(info.isDisabled()); setIcon(iconDrawable); } 在Launcher.java的onResume()和onPause()中分别开始和暂停
@Override protected void onResume() { ...... /* begin */ DeskClockUtil.getInstance().onResume(this); /* end */ if (mLauncherCallbacks != null) { mLauncherCallbacks.onResume(); } }@Override protected void onPause() { // Ensure that items added to Launcher are queued until Launcher returns InstallShortcutReceiver.enableInstallQueue(InstallShortcutReceiver.FLAG_ACTIVITY_PAUSED); super.onPause(); mPaused = true; mDragController.cancelDrag(); mDragController.resetLastGestureUpTime(); // We call onHide() aggressively. The custom content callbacks should be able to // debounce excess onHide calls. if (mWorkspace.getCustomContentCallbacks() != null) { mWorkspace.getCustomContentCallbacks().onHide(); } if (mLauncherCallbacks != null) { mLauncherCallbacks.onPause(); } /* begin */ DeskClockUtil.getInstance().onPause(); /* end */ } 这样就可以了，如果想要加秒针，在IconUtil中再把秒针画出来就行。
还有日历的动态图标也可以用同样的方法实现
总结
以上所述是小编给大家介绍的Android 8.1 Launcher3实现动态指针时钟功能，希望对大家有所帮助，如果大家有任何疑问请给我留言，小编会及时回复大家的。在此也非常感谢大家对VEVB武林网网站的支持！
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