How to draw on ActionBar tab when using ActionBarSherlock in Android?

问题:

I am using ActionBarSherlock to provide ActionBars for pre HoneyComb devices.

My Activity has four fragments namely 1. User 2. Chat 3. Video 4. Extra, see image

I have created actionBar using following code:-

            actionBar = getSupportActionBar();         actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);          actionBar.setTitle("Meeting");         actionBar.setDisplayShowHomeEnabled(false);         actionBar.setDisplayShowCustomEnabled(false);         actionBar.setDisplayShowTitleEnabled(false);          /* Set Custom view */           ActionBar.Tab tab = actionBar.newTab();         // tab.setText("Meeting Users");         tab.setIcon(R.drawable.users);         tab.setTabListener(this);         actionBar.addTab(tab);          tab = actionBar.newTab();         // tab.setText("Chat");         tab.setIcon(R.drawable.chat);         tab.setTabListener(this);         actionBar.addTab(tab);          tab = actionBar.newTab();         // tab.setText("Video");         tab.setIcon(R.drawable.video_call);         tab.setTabListener(this);         tab.select();         actionBar.addTab(tab);          tab = actionBar.newTab();         // tab.setText("Extra");         tab.setIcon(R.drawable.extra);         tab.setTabListener(this);         actionBar.addTab(tab); 

I want to draw something on those tabs, for example draw and/OR blink on chat tab, whenever chat messages arrives and user is on some other tab.

How can I do this ? please help.

回答1:

Use custom view for your tabs

  ActionBar.Tab tab = getSupportActionBar().newTab();   tab.setCustomView(R.layout.custom_tab_view); 

Then you can get views on your custom layout and make blinking

回答2:

This is How I solved my problem, Hope it can be useful for someone else too....

First I created a CutomImageView by extending ImageView

package com.myexample.newsessionwindowsrbrdemo;  import android.content.Context; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.renderscript.Font.Style; import android.widget.ImageView;  public class CustomImageView extends ImageView {     private int notificationCount;      /**      * @param context      */     public CustomImageView(Context context) {         super(context);         notificationCount = 0;     }      public synchronized void incrementNotification() {         notificationCount--;         this.invalidate();     }      public synchronized void decrementNotification() {         notificationCount++;         this.invalidate();     }      /**      * @return the notificationCount      */     public synchronized int getNotificationCount() {         return notificationCount;     }      /**      * @param notificationCount      *            the notificationCount to set      */     public synchronized void setNotificationCount(int notificationCount) {         this.notificationCount = notificationCount;         this.invalidate();     }      /*      * (non-Javadoc)      *       * @see android.widget.ImageView#onDraw(android.graphics.Canvas)      */     @Override     protected void onDraw(Canvas canvas) {         System.out.println("OnDraw is called");         super.onDraw(canvas);         Paint paint = new Paint();         paint.setColor(Color.RED);         paint.setStyle(Paint.Style.FILL);         paint.setFakeBoldText(true);         paint.setTextSize(15);         canvas.drawText(String.valueOf(notificationCount), 15, 20, paint);     }  } 

Then While creating tabs, I used this image as

/* Set Custom view */

    mView = new CustomImageView(this);     mView.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,             LayoutParams.FILL_PARENT));      mView.setBackgroundResource(R.drawable.users);     ActionBar.Tab tab = actionBar.newTab();     tab.setCustomView(mView);     tab.setTabListener(this);     actionBar.addTab(tab); 

Now whenever the notification changes I call increment/decrement or setter method of CustomImageView and new Notifications are displayed on the image..

Suggestions to improve this solution are really welcome...

文章来源: How to draw on ActionBar tab when using ActionBarSherlock in Android?