如何使用通知数在操作栏中创建一个图标?

我想在操作栏中在通知数量内部制作一个通知图标。

例如( Google Adsence ):

Action Bar Google Adsence

我在stackoverflow上find了这个答案,但它没有完全回答我的问题,因为在这种情况下它只是数字而不是带有数字的图标: 带有计数的Actionbar通知图标

Solutions Collecting From Web of "如何使用通知数在操作栏中创建一个图标?"

经过对SO的几乎所有资源的大量尝试后,我转向了博客; 成功。 我想分享一下对我有用的东西(Api> = 13)。

让我们从在代码中使用的方式开始:

public boolean onCreateOptionsMenu(Menu menu) { //inflate menu getMenuInflater().inflate(R.menu.menu_my, menu); // Get the notifications MenuItem and LayerDrawable (layer-list) MenuItem item = menu.findItem(R.id.action_notifications); LayerDrawable icon = (LayerDrawable) item.getIcon(); // Update LayerDrawable's BadgeDrawable Utils2.setBadgeCount(this, icon, 2); return true; } 

menu_my.xml

    

这个类可以方便地制作BadgeDrawable

 public class BadgeDrawable extends Drawable { private float mTextSize; private Paint mBadgePaint; private Paint mTextPaint; private Rect mTxtRect = new Rect(); private String mCount = ""; private boolean mWillDraw = false; public BadgeDrawable(Context context) { //mTextSize = context.getResources().getDimension(R.dimen.badge_text_size); mTextSize = 12F; mBadgePaint = new Paint(); mBadgePaint.setColor(Color.RED); mBadgePaint.setAntiAlias(true); mBadgePaint.setStyle(Paint.Style.FILL); mTextPaint = new Paint(); mTextPaint.setColor(Color.WHITE); mTextPaint.setTypeface(Typeface.DEFAULT_BOLD); mTextPaint.setTextSize(mTextSize); mTextPaint.setAntiAlias(true); mTextPaint.setTextAlign(Paint.Align.CENTER); } @Override public void draw(Canvas canvas) { if (!mWillDraw) { return; } Rect bounds = getBounds(); float width = bounds.right - bounds.left; float height = bounds.bottom - bounds.top; // Position the badge in the top-right quadrant of the icon. float radius = ((Math.min(width, height) / 2) - 1) / 2; float centerX = width - radius - 1; float centerY = radius + 1; // Draw badge circle. canvas.drawCircle(centerX, centerY, radius, mBadgePaint); // Draw badge count text inside the circle. mTextPaint.getTextBounds(mCount, 0, mCount.length(), mTxtRect); float textHeight = mTxtRect.bottom - mTxtRect.top; float textY = centerY + (textHeight / 2f); canvas.drawText(mCount, centerX, textY, mTextPaint); } /* Sets the count (ie notifications) to display. */ public void setCount(int count) { mCount = Integer.toString(count); // Only draw a badge if there are notifications. mWillDraw = count > 0; invalidateSelf(); } @Override public void setAlpha(int alpha) { // do nothing } @Override public void setColorFilter(ColorFilter cf) { // do nothing } @Override public int getOpacity() { return PixelFormat.UNKNOWN; } } 

这个类有助于设置数字。

 public class Utils2 { public static void setBadgeCount(Context context, LayerDrawable icon, int count) { BadgeDrawable badge; // Reuse drawable if possible Drawable reuse = icon.findDrawableByLayerId(R.id.ic_badge); if (reuse != null && reuse instanceof BadgeDrawable) { badge = (BadgeDrawable) reuse; } else { badge = new BadgeDrawable(context); } badge.setCount(count); icon.mutate(); icon.setDrawableByLayerId(R.id.ic_badge, badge); } } 

并且mui importanres/drawable一个drawable(如布局):

 < ?xml version="1.0" encoding="utf-8"?>      

祝你好运!